JP2020037513A - Articles and methods for controlled bonding of polymer surfaces with carriers - Google Patents

Abstract

A method for controlled bonding of a substrate and a carrier for forming a reusable article of the carrier that can withstand FPD processing.
A method for controllably bonding a substrate to a carrier to form an article includes obtaining a glass substrate having a substrate binding surface having a first surface energy and having a carrier binding surface having a second surface energy. Obtaining a glass carrier, depositing a surface-modified layer on the carrier-bound surface so as to reduce the surface energy of the carrier-bound surface, and bonding the substrate-bound surface to the carrier-bound surface via the surface-modified layer. The surface modification layer is a plasma polymerized fluoropolymer deposited by plasma polymerization of a mixture comprising the etching gas and the polymer forming gas, wherein the polymer forming gas is less than 40% of the mixture.
[Selection diagram] Fig. 1

Description

priority

  This application claims the benefit of priority from US Provisional Patent Application No. 61 / 93,924, filed January 27, 2014, the contents of which are incorporated herein by reference in its entirety.

  The present invention relates to an article and a method for treating a soft sheet on a carrier, and more particularly to an article and a method for treating a soft glass sheet on a glass carrier.

  Flexible substrates offer the prospect of cheaper devices using roll-to-roll processing and the potential to produce thinner, lighter, more flexible and durable displays. However, the technologies, equipment, and processes required for high quality display roll-to-roll processing have also not been fully developed. Panel manufacturers have already invested heavily in machine tools for processing large glass sheets, so using a sheet-to-sheet processing method to laminate flexible substrates to carriers and produce display devices is becoming thinner. Present a shorter-term solution to develop a lighter and more flexible display value proposition. The display was demonstrated on a polymer sheet, such as polyethylene naphthalate (PEN), in which case the device fabrication was a sheet-to-sheet where PEN was laminated to a glass carrier. The upper temperature limit of PEN limits the quality of the device and the processes that can be used. In addition, the high permeability of the polymer substrate results in environmental degradation of the OLED device, which requires almost hermetic packaging. Although thin film encapsulation offers the promise of overcoming this limitation, it has not yet been demonstrated to provide large and acceptable yields.

  Similarly, display devices can be manufactured using a glass carrier laminated to one or more thin glass substrates. It is anticipated that the low permeability and improved temperature and chemical resistance of this thin glass will enable flexible displays with higher performance and longer life.

  However, flat panel display (FPD) processes, thermal, vacuum, solvent and acidic, and ultrasonic, require robust bonding of thin glass bonded to a carrier. FPD processes typically involve vacuum deposition (sputtering of metals, transparent conductive oxides and oxide semiconductors, chemical vapor deposition (CVD) of amorphous silicon, silicon nitride, and silicon dioxide, and dry etching of metals and insulators). Thermal processes (CVD at about 300-400 ° C., p-Si crystallization up to 600 ° C., annealing of oxide semiconductor at 350-450 ° C., dopant annealing up to 650 ° C., and contact annealing at about 200-350 ° C.) Acid etching (metal etching, oxide semiconductor etching), solvent exposure (photoresist removal, polymer encapsulation deposition), and ultrasonic exposure (photoresist solvent removal and typically in alkaline solutions) Washing with water).

  Adhesive wafer bonding is widely used in semiconductor processing for micro-electro-mechanical systems (MEMS) and back-end processes where the process is less demanding. Commercially available adhesives by Brewer Science and Henkel are typically thick polymer adhesive layers that are 5-200 micrometers thick. The large thickness of these layers creates the potential for large amounts of volatiles, trapped solvents, and adsorbed species that contaminate the FPD process. These materials thermally decompose and outgas above about 250 ° C. These materials can also contaminate downstream processes by acting as sinks for gases, solvents and acids (which can outgas in subsequent processes).

  US Patent Application Publication No. US 2005/0128129 A1 filed February 8, 2012, entitled Processing Flexible Glass with a Carrier, describes the concept of bonding a thin sheet, for example, a soft glass sheet, to a carrier, first by van der Waals forces, Then, while maintaining the ability to remove portions of the thin sheet after processing of the thin sheet / carrier, the bonding strength in certain areas is increased to further increase the device (eg, electronic or display device, electronic or display device). It is disclosed to include steps for forming a component, an organic light emitting device (OLDE) material, a photovoltaic (PV) structure, or a thin film transistor. At least a portion of the thin glass is bonded to the carrier, i.e., to prevent device processing fluid from entering between the thin sheet and the carrier, thereby reducing the chance of contaminating downstream processes, i.e., The bonded seal portion between the thin sheet and the carrier is air-tight, and in some preferred embodiments, the seal wraps around the outside of the article, thereby removing any area of the sealed article from Alternatively, the intrusion of a liquid or gas into any region is prevented.

  U.S. Pat. No. 6,077,095 then describes a low temperature polysilicon (LTPS) (lower temperature than solid state crystallization process that can be up to about 750.degree. C.) device fabrication process at temperatures up to 600.degree. It is disclosed that a wet etching environment may be used. These conditions limit the materials that can be used and place high demands on the carrier / thin sheet. Therefore, it would be desirable to utilize the manufacturer's existing capital infrastructure and to eliminate the loss of bond strength or contamination between the thin glass and carrier at higher processing temperatures, and to reduce the thickness of the thin glass, i.e., the thickness Is a carrier technique where the thin glass can be easily peeled off from the carrier at the end of the process.

  One commercial advantage over the approach disclosed in U.S. Pat. No. 6,037,045 is that, as mentioned in U.S. Pat. The advantage is that existing capital investments in processing equipment can be utilized, while gaining the advantages of thin glass sheets. Moreover, by that approach: flexibility with respect to cleaning and surface treatment of the thin glass sheet and carrier to promote bonding; flexibility with respect to strengthening the bond between the thin sheet and the carrier in the bonding area; non-bonding ( Or reduced / low-strength bonding) areas for flexibility in maintaining the releasability of the thin sheet from the carrier; and flexibility in cutting the thin sheet to facilitate removal from the carrier. Will be possible.

In the glass-to-glass bonding process, the glass surface is cleaned to remove all metal, organic and particulate residues, leaving a mostly silanol terminated surface. The glass surfaces are first brought into intimate contact, where they are attracted together by van der Waals forces and / or hydrogen bonding forces. Heat and optional pressure condense the silanol groups on the surface to form strong covalent Si-O-Si bonds across the interface, permanently bonding the glass pieces. Metal, organic and particulate residues prevent bonding by obscuring the surface and preventing the close contact required for bonding. Since the number of bonds per unit area is determined by the probability of the two silanol species on the opposing surface reacting and dehydrating and condensing, a high silanol surface concentration is also required to form strong bonds. Zhuravlel, for sufficiently hydrated silica, average number of hydroxyl per nm ² was reported to be 4.9 from 4.6 (non-patent document 1). In U.S. Pat. No. 6,086,097, a non-bonded area is formed within the bonded perimeter, and the primary mode described for forming such a non-bonded area is to increase the surface roughness. An average surface roughness of Ra greater than 2 nm may prevent a glass-to-glass bond from forming during the high temperatures of the bonding process. US Patent Application Publication No. US 2003/0128129 filed December 13, 2012 by the same inventor, entitled Facilitated Processing for Controlling Bonding Between Sheet and Carrier, controls van der Waals and / or hydrogen bonding between a carrier and a thin glass sheet. By doing so, a controlled bonding area is formed, but a covalent bonding area is still used as well. Thus, while the articles and methods for treating thin sheets having a carrier in U.S. Patent Nos. 6,064,026 and 5,078,036 can withstand the harsh environment of FPD processing, but undesired for some applications, glass breakage is undesirable. The covalent bond with an adhesive force of about 1000-2000 mJ / m ² , comparable to the strength, for example, a strong covalent bond between the thin glass and the glass support in the Si-O-Si covalently bonded region, the carrier Is prevented from being reused. Prying or peeling cannot be used to separate the covalently bonded portions of the thin glass from the carrier, and therefore the entire thin sheet cannot be removed from the carrier. Instead, the unbonded area with the device thereon is scored and removed, leaving the bonded perimeter of the thin glass sheet on the carrier.

US Provisional Patent Application No. 61/596727 US Provisional Patent Application No. 61/736880

Zhuravlel, L.T., The Surface Chemistry of Amorphous Silika, Zhuravlev Model, Colloids and Surfaces A: Physiochemical Engineering Aspects 173 (2000) 1-38

  In view of the above, to withstand the rigors of FPD processing, including high temperature processing (without gassing that would be incompatible with the semiconductor or display manufacturing process in which it is used), and yet to process another thin sheet There is a need for thin sheet and carrier articles that can remove the entire area of the thin sheet from the carrier (either all at once or zone by zone) so that the carrier can be recycled.

  The present specification describes a method for forming a temporary bond with a carrier that is strong enough to withstand FPD processing (including LTPS processing) but weak enough to release the sheet from the carrier, even after high temperature processing. A method for controlling the adhesion between thin sheets is described. Such controlled bonds can be utilized to form articles with reusable carriers, or articles with controlled and covalent bond areas between the carrier and the sheet. More particularly, the present disclosure relates to a method for controlling both room temperature van der Waals and / or hydrogen bonding and high temperature covalent bonding between a thin sheet and a carrier, the thin sheet, the carrier, or both. A surface modifying layer (including various materials and associated surface heat treatments) provided thereon. Still more particularly, room temperature bonding may be controlled to be sufficient to hold the thin sheet and carrier together during the vacuum, wet, and / or ultrasonic cleaning processes. At the same time, the high temperature covalent bonds may be controlled to prevent permanent bonding between the thin sheet and the carrier during high temperature processing, as well as to maintain sufficient bonding to prevent delamination during high temperature processing. In an alternative embodiment, the surface modifying layer may provide additional processing options, e.g., between the carrier and the sheet, even after cutting the article into smaller pieces for additional device processing. In order to maintain the airtightness of the substrate, the various controlled bonding areas (carriers and sheets may be sufficiently stiffened throughout the various processes, including vacuum, wet, and / or ultrasonic cleaning, along with the covalent bonding area). (Which remains bound). Furthermore, some surface modification layers provide control of the bond between the carrier and the sheet, while at the same time maintaining the harshest conditions in an FPD (eg, LTPS) processing environment, including, for example, high temperature and / or vacuum processing. Reduces outgassing in. Furthermore, in an alternative embodiment, some surface modification layers may be used on a carrier with a glass binding surface to controllably bind a thin sheet with a polymer binding surface. The polymer binding surface may be part of a thin sheet of polymer on which the electrons or other structures are formed, or the polymer binding surface may be formed on the electrons or other structures on which the electrons or other structures are formed. May be a part of a composite sheet provided with a glass layer.

  Additional features and advantages are set forth in the following detailed description, some of which will be readily apparent to those skilled in the art from the description or may be varied as illustrated in the written description and accompanying drawings. It will be appreciated by implementing the various aspects. The foregoing general description and the following detailed description are merely exemplary of various embodiments, which are provided to provide either an overview or a framework for understanding the nature and features of the claimed invention. It will be understood that it is intended.

  The accompanying drawings are included to provide a further understanding of the principles of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiments and, together with the description, serve to explain, by way of example, the principles and operation of the present invention. It should be understood that various features disclosed in the specification and drawings can be used in any combination and in all combinations. By way of non-limiting example, various features may be combined with one another as set forth in the appended claims.

Schematic side view of an article having a carrier bound to a sheet thinner than the surface modifying layer between FIG. 2 is an exploded view of the article of FIG. Graph of surface hydroxyl concentration on silica as a function of temperature Graph of surface energy of SC1 cleaned glass sheet as a function of annealing temperature Graph of the surface energy of a thin film fluoropolymer deposited on a glass sheet as a function of the proportion of one of the constituent materials from which the film was made Schematic plan view of a thin sheet bonded to a carrier by a bonding area Schematic side view of glass sheet laminate Exploded view of one embodiment of the laminate of FIG. Schematic of test arrangement A family of graphs of surface energy (for different parts of the test arrangement of FIG. 9) versus time for various materials under different conditions. Graph of change of bubble area% against temperature for various materials Another graph of bubble area% change versus temperature for various materials Graph of the surface energy of a fluoropolymer film deposited on a glass sheet as a function of the proportion of one of the gases used during the deposition Graph of the surface energy of a fluoropolymer film deposited on a glass sheet as a function of the proportion of one of the gases used during the deposition Graph of surface energy versus deposition time for a surface modified layer Graph of deposition time versus logarithmic and logarithmic scale for the surface modified layer Graph of surface energy versus treatment temperature for different surface modification layers Graph of surface coverage of surface modified layer Summary of the performance of organic transistors fabricated on a 200 micron PEN film bonded to a glass carrier

  In the following detailed description, for purposes of explanation and not limitation, example embodiments that disclose specific details are set forth in order to provide a thorough understanding of various principles of the invention. It will be apparent, however, to one skilled in the art, having had the benefit of the present disclosure, that the present invention may be practiced in other embodiments that depart from the specific details disclosed herein. In addition, descriptions of well-known devices, methods and materials may be omitted so as to not obscure the description of various principles of the present invention. Finally, whenever applicable, like reference numerals refer to like elements.

  Ranges can be expressed herein as from "about" one particular value, and / or to "about" another value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another embodiment. It will further be appreciated that each endpoint of the range is significant both with respect to the other endpoint and independently of the other endpoint.

  The directional terms used herein, e.g., top, bottom, right, left, front, back, top, bottom, are used only with respect to the drawings drawn and are not intended to imply an absolute orientation .

  As used herein, a noun refers to a plurality of objects, unless otherwise indicated. Thus, for example, reference to "a component" includes embodiments having more than one such component, unless otherwise specified.

  In U.S. Pat. Nos. 6,059,009 and 5,097,098, at least some portions of the thin glass sheet are treated with a "glass" on the carrier, so that devices machined on the thin glass sheet can be removed from the carrier. A solution is provided that remains in the "unbound" state. However, the outer perimeter of the thin glass is permanently (or covalently or hermetically) bonded to the carrier glass by the formation of Si-O-Si covalent bonds. This covalently bonded perimeter prevents reuse of the carrier. This is because thin glass cannot be removed in this permanently bonded area without damaging the thin glass and the carrier.

  The carrier is typically a display grade glass substrate to maintain convenient surface features. Thus, in some situations, simply discarding the carrier after one use is wasteful and costly. Therefore, it is desirable to be able to reuse a carrier to process multiple thin sheet substrates to reduce the cost of display manufacturing. The present disclosure relates to high-temperature processing (high-temperature processing is processing at a temperature of 400 ° C. or more and varies depending on the type of device being manufactured, for example, amorphous silicon or amorphous indium gallium zinc oxide (IGZO) Temperatures up to about 450 ° C. as in backplane processing, up to about 500-550 ° C. as in crystalline IGZO processing, or up to about 600-650 ° C. as typical for LTPS processes). Enables processing of thin sheets through the harsh environment of an FPD processing line that includes, but still damages the thin sheet or carrier (eg, one of the carrier and the thin sheet cracks or chips into two or more pieces). Thinner sheet can be more easily removed from the carrier, thereby reusing the carrier Kill described the articles and methods.

  As shown in FIGS. 1 and 2, the article 2 has a thickness 8, a carrier 10 having a thickness 18, a thin sheet 20 having a thickness 28 (ie, but not limited to, for example, 10 ５０50 micrometers, 50-100 micrometers, 100-150 micrometers, 150-300 micrometers, 300, 250, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, 100, 90 , 80, 70, 60, 50, 40, 30, 20, or 10 micrometers), and a surface modification layer 30 having a thickness 38. Article 2 may have a thickness of less than 300 micrometers in thin sheet 20 itself, but a thicker sheet (ie, greater than about 0.4 mm, for example, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm). , 0.9 mm, or 1.0 mm) in a device designed for processing thin sheets 20. That is, thickness 8, which is the sum of thicknesses 18, 28, and 38, is designed such that a portion of the device (eg, a device designed to place electronic device components on a substrate sheet) processes. Designed to be equivalent to the thickness of the thicker sheet made. For example, if the processing equipment is designed for a 700 micrometer sheet, and the thin sheet has a thickness 28 of 300 micrometers, and the thickness 38 is insignificant, then the thickness 18 would be 400 micrometers. Will be selected. That is, the surface modification layer 30 is not shown to scale; instead, it is greatly exaggerated for illustration only. Moreover, the surface modification layer is indicated by a notch. In practice, the surface modification layer will be uniformly disposed on the bonding surface 14 if it provides a reusable carrier. Typically, the thickness 38 is on the order of nanometers, for example, 0.1 to 2.0, or 10 nm, and in some cases, up to 100 nm. The thickness 38 may be measured by an ellipsometer. Moreover, the presence of the surface modification layer will be detected by surface chemical analysis, for example, ToF Sims mass spectrometry. Thus, the contribution of thickness 38 to article thickness 8 is insignificant and determines the appropriate thickness 18 of carrier 10 to process a given thin sheet 20 having thickness 28. May be ignored in the calculations for However, as long as the surface modification layer 30 has any significant thickness 38, the thickness 18 of the carrier 10 for the given thickness 28 of the thin sheet 20 and the given thickness for which the processing equipment is designed May be accounted for in determining its thickness.

  The carrier 10 has a first surface 12, a bonding surface 14, an outer circumference 16, and a thickness 18. Further, carrier 10 may be of any suitable material, including, for example, glass. The support need not be glass, but can instead be ceramic, glass ceramic, or metal (surface energy and / or bonding controlled in a manner similar to that described below for glass supports). Will be). If the carrier 10 is made of glass, it may be of any suitable composition, including aluminosilicates, borosilicates, aluminoborosilicates, soda-lime silicates, depending on the end use. Thus, it may or may not contain an alkali. The thickness 18 may be about 0.2 to 3 mm or greater, for example, 0.2, 0.3, 0.4, 0.5, 0.6, 0.65, 0.7, 1.0 , 2.0, or 3 mm or more, depending on the thickness 28 and, if insignificant as described above, the thickness 38. Moreover, the carrier 10 may be manufactured from one layer, as shown, or from multiple layers bonded together (including multiple thin sheets of the same or different materials). Further, the carrier may be of the first generation size or larger, for example, second generation, third generation, fourth generation, fifth generation, eighth generation or larger (eg, 100 mm × 100 mm to 3 meters x 3 meters or larger sheet size).

  The thin sheet 20 has a first surface 22, a bonding surface 24, an outer periphery 26, and a thickness 28. The perimeters 16 and 26 may be of any shape and may be the same or different. Further, the thin sheet 20 may be of any suitable material, including, for example, glass, ceramic, or glass-ceramic. In some cases, thin sheet 20 may be a polymer sheet or a composite sheet having a polymer and / or glass binding surface. If the thin sheet 20 is made of glass, it may be of any suitable composition including aluminosilicate, borosilicate, aluminoborosilicate, soda-lime silicate, Accordingly, an alkali may or may not be contained. The coefficient of thermal expansion of the thin sheet could be matched relatively closely with that of the carrier to prevent warping of the article during processing at high temperatures. If the article 2 is processed at lower temperatures where CTE matching is not such a concern, a thin sheet of polymer can be used with the glass carrier. Of course, there will be other examples where a polymer sheet may be used with a glass carrier. The thickness 28 of the thin sheet 20 is not more than 300 micrometers as described above. Further, the thin sheet may be of the first generation size or larger, for example, second generation, third generation, fourth generation, fifth generation, eighth generation or larger (eg, Sheet size from 100 mm x 100 mm to 3 m x 3 m or larger).

  Article 2 not only needs to have the exact thickness to be processed in existing equipment, but also needs to sometimes be able to withstand the harsh environment in which the processing is performed. For example, flat panel display (FPD) processing will include wet, ultrasonic, vacuum, and in some cases, high temperature (eg, 400 ° C. or higher) processing. For certain processes, as described above, the temperature will be above 500 ° C, or above 600 ° C, and up to 650 ° C.

  To withstand the harsh environment in which the article 2 is processed, such as during FPD manufacturing, for example, the bonding surface 14 should be bonded to the bonding surface 24 with sufficient strength so that the thin sheet 20 does not separate from the carrier 10. It is. And this strength should be maintained throughout processing so that the thin sheet 20 does not separate from the carrier 10 during processing. Further, in order to allow the thin sheet 20 to be removed from the carrier 10 (so that the carrier 10 can be reused), the bonding surface 14 may be provided with a bonding surface 24 with an initially designed bonding force and / or, for example, when the article is heated to high temperatures, The bond should not be too strong, for example, due to any of the bonding forces resulting from a change in the originally designed bonding force, such as would occur when processing at temperatures above 400 ° C. Surface modification layer 30 may be used to control the strength of the bond between bonding surface 14 and bonding surface 24 to achieve both of these objectives. The controlled binding force is controlled by adjusting the polar and non-polar surface energy components of the thin sheet 20 and the carrier 10, the van der Waals (and / or hydrogen bonding) energy and the covalent attractive energy relative to the total adhesion energy. Is achieved by controlling This controlled bonding involves FPD processing (wet, ultrasonic, vacuum, and thermal processes that include temperatures of 400 ° C. or higher, in some cases, 500 ° C. or higher, or 600 ° C. or higher, and up to 650 ° C.). ) And remain peelable with the application of sufficient separating force and with a force that does not cause catastrophic damage to the thin sheet 20 and / or the carrier 10. Such peeling allows for the removal of the thin sheet 20 and the devices manufactured thereon, and also allows for the reuse of the carrier 10.

  Although the surface modification layer 30 is shown as a solid layer between the thin sheet 20 and the carrier 10, it need not be. For example, layer 30 may be approximately 0.1 to 2 nm thick and may not completely cover all of bonding surface 14. For example, the coverage may be 100% or less, 1% to 100%, 10% to 100%, 20% to 90%, or 50% to 90%. In other embodiments, layer 30 may be up to 10 nm thick, or in other embodiments, even up to 100 nm thick. The surface modification layer 30 may not be in contact with one or the other of the carrier 10 and the thin sheet 20, but may be considered to be disposed between the carrier 10 and the thin sheet 20. In any event, an important feature of the surface modification layer 30 is that it alters the ability of the bonding surface 14 to bond to the bonding surface 24, thereby controlling the bonding strength between the carrier 10 and the thin sheet 20. is there. The material and thickness of the surface modification layer 30 and the treatment of the bonding surfaces 14, 24 before bonding can be used to control the bond strength (adhesion energy) between the carrier 10 and the thin sheet 20.

  Generally, the adhesion energy between two surfaces is:

(“A theory for the estimation of surface and interfacial energies. I. derivation and application to interfacial tension”, LA Girifalco and RJ Good, J. Phys. Chem., V 61, p904), where γ ₁ , Γ ₂ and γ ₁₂ are the surface energies of surface 1 and surface 2 and the interfacial energy of surfaces 1 and 2, respectively. The individual surface energy is usually a combination of two terms: the variance component γ ^d , and the polar component γ ^p :

If the attachment is primarily due to London dispersive forces (γ ^d ) and polar forces, such as hydrogen bonding (γ ^p ), the interfacial energy is:

(Girifalco and R. J. Good, supra).

  Substituting (3) for (1) gives the adhesion energy:

Will be approximated as In the above equation (4), only the van der Waals (and / or hydrogen bond) component of the adhesion energy is considered. These include polar-polar interactions (cassoms), polar-non-polar interactions (Debye) and non-polar-non-polar interactions (London). However, there will be other attractive energies, such as covalent and electrostatic bonds. So, in a further generalized form, the previous expression is:

Where ω _c and ω _e are covalent and electroadhesive energies. This covalent attachment energy is fairly common, as in silicon wafer bonding, where the initial hydrogen bond pair of the wafer is heated to a temperature high enough to convert many or all of the silanol-silanol hydrogen bonds to Si-O-Si covalent bonds. It is a target. Initial room temperature hydrogen bonding results in an attachment energy on the order of about 100-200 mJ / m ² that allows for separation of the bonded surfaces, while being achieved during high temperature processing (approximately 400-800 ° C.). Fully covalently bonded wafer pairs have an adhesion energy of about 1000-3000 mJ / m ^{2 which} prevents separation of the bonded surface; instead, the two wafers function as a monolith. On the other hand, if both surfaces are fully coated with a low surface energy material, e.g., a fluoropolymer, with a thickness large enough to shield the effects of the underlying substrate, then the adhesion energy will be: It will be of that coating material and will be very small and will result in low or no adhesion between the bonding surfaces 14, 24, so that the thin sheet 20 cannot be processed on the carrier 10. Would. Consider two extreme cases: (a) two standard clean 1 saturated with silanol groups bonded together at room temperature by hydrogen bonding (whereby the attachment energy is on the order of about 100-200 mJ / m ² ) the known as SC1 in the art) cleaned glass surface, which is later converted to silanol groups on the Si-O-Si covalent bond (thereby adhesion energy is the 1000~3000mJ / m ² Is heated to a high temperature. This latter adhesion energy is too high for the pair of glass surfaces to be removable; (2) has low surface adhesion energy (about 12 mJ / m ² per surface) that binds at room temperature and is heated to high temperatures. Two glass surfaces completely coated with fluoropolymer. In this latter case (b), not only is the surface unbound (because the total attachment energy of about 24 mJ / m ² when the surface is attached is too low), but also there is no polar reactive group (or too little) ) So it does not bond even at high temperatures. Between the cases these two extremes, it is possible to produce a controlled binding of desired extent, a range, for example, there are adhesion energy between 50~1000mJ / m ^2. Accordingly, the inventors of the present application provide an adhesion energy that is between these two extremes, and a pair of glass substrates (eg, glass carrier 10 and thin glass sheet 20) bonded together through the rigors of FPD processing. Not only is it sufficient to maintain a stable bond, but also after the processing is completed, such that the thin sheet 20 can be removed from the carrier 10 (eg, even after high temperature processing above 400 ° C.). Various methods have been found to provide a tunable surface modification layer 30 so as to be able to. Further, the removal of the thin sheet 20 from the carrier 10 can be performed by mechanical force, at least in a manner such that the thin sheet 20 is not catastrophically damaged, and preferably such that the carrier 10 is not catastrophically damaged. it can.

  Equation (5) states that the adhesion energy is a function of four surface energy parameters, in addition to the shared and electrostatic energies, if any.

  Appropriate deposition energy can be achieved by judicious selection of the surface modifier, ie, the surface modification layer 30, and / or heat treatment of the surface prior to bonding. Appropriate attachment energies may be obtained by the choice of chemical modifiers on either or both of the binding surfaces 14 and 24. The chemical modifier in turn results from van der Waals (and / or hydrogen bonding, these terms are used interchangeably throughout the specification) as well as high temperature processing (eg, above about 400 ° C.). Controls both possible covalent attachment energies. For example, if the binding surface of SC1 cleaning glass (which is initially saturated with silanol groups with a high polarity component of surface energy) is selected and coated with a low energy fluoropolymer, the polar and non-polar groups will cause The partial coverage of the surface is controlled. This not only provides control of the initial van der Waals (and / or hydrogen) bonding at room temperature, but also controls the degree / degree of covalent bonding at elevated temperatures. Control of the initial van der Waals (and / or hydrogen) bonding at room temperature allows for vacuum and / or spin rinse dry (SRD) type processing, bonding of one surface to the other, And in some cases, it is done to provide an easily formed bond of one surface to the other. Here, the easily formed connection is achieved by the application of an externally applied force over the entire area of the thin sheet 20, as is done when pressing the thin sheet 20 against the carrier 10 by means of a squeegee or under reduced pressure. And can be performed at room temperature. That is, this initial van der Waals bond holds the thin sheets and carriers together, at least to a minimum extent, so that they do not separate when one is held and the other can be exposed to gravity. To provide a binding. In most cases, the initial van der Waals (and / or hydrogen) bonds are of such an extent that the article experiences vacuum, SRD, and sonication without the thin sheet detaching from the carrier. Van der Waals (and and) by their surface modification layer 30 (including the surface treatment of the material from which it is made and / or the surface to which it is applied) and / or their heat treatment before bonding the bonding surfaces together This precise control, at appropriate levels of both (and / or hydrogen bonding) and covalent interactions, allows the thin sheet 20 to be bonded to the carrier 10 during processing of the FPD style, while at the same time, after processing of the FPD style. Achieving the desired adhesion energy that allows the thin sheet 20 to separate from the carrier 10 (with appropriate force to avoid damage to the thin sheet 20 and / or the carrier). Moreover, in appropriate circumstances, one or both glass surfaces could be charged to provide another level of control of the deposition energy.

  FPD processing, such as p-Si and oxide TFT fabrication, will typically result in a glass-to-glass bond with the glass carrier 10 of the thin glass sheet 20 without the surface modification layer 30. , More than 400 ° C., more than 500 ° C., and in some cases, temperatures above 600 ° C. up to 650 ° C. Thus, controlling the formation of Si-O-Si bonds results in a reusable carrier. One way to control the formation of Si-O-Si bonds at elevated temperatures is to reduce the concentration of surface hydroxyls on the surface to be bonded.

  As shown in FIG. 3, which is an Iler plot of surface hydroxyl concentration on silica as a function of temperature (RK Iller: The Chemistry of Silica, Wiley-Interscience, New York, 1979), hydroxyl per square nm ( The number of OH groups decreases with increasing surface temperature, and thus heating the silica surface (and, by way of illustration, the glass surface, eg, bonding surface 14 and / or bonding surface 24) will reduce the concentration of surface hydroxyls. The probability of the hydroxyls on the two glass surfaces interacting is reduced, this reduction in the concentration of surface hydroxyls, in turn, reduces the Si-O-Si bonds formed per unit area and increases the adhesion However, to eliminate surface hydroxyls, long exposures at high temperatures (> 750 ° C. to completely eliminate surface hydroxyls) Lumpur time is required. Such long annealing times and higher annealing temperatures becomes a costly process, because it is typical to exceed the strain point of the glass for a display, the impractical process.

From the previous analysis, we have found that articles with thin sheets and carriers suitable for FPD processing (including LTPS processing) can be manufactured by balancing the following three concepts:
(1) Moderate adhesion energy sufficient to promote initial room temperature bonding and withstand non-high temperature FPD processes, such as vacuum, SRD, and / or sonication (eg, prior to bonding the surfaces, Carrier by controlling van der Waals (and / or hydrogen) bonds to control the initial room temperature bond to produce a surface energy of greater than 40 mJ / m ² per surface) And / or modifying the bonding surface of the thin sheet;
(2) Thermally enough to withstand the FPD process without delamination and / or outgassing that can cause unacceptable contamination in device fabrication, eg, semiconductor and / or display fabrication processes where the article will be used. Surface modification of the support and / or thin sheet in a highly stable manner; and (3) hydroxyl concentration on the support surface, and other species capable of forming strong covalent bonds at elevated temperatures (eg, temperatures above 400 ° C.). Of the carrier and the thin sheet, even after high temperature processing (especially through a thermal process in the range of 500-650 ° C., as in the FPD process). The adhesion does not damage at least the thin sheet (and preferably does not damage either the thin sheet or the carrier) ) The carrier such that the separating force can release the thin sheet from the carrier, but still maintain the carrier and the thin sheet within a range that is sufficient to maintain the bond between them so that they do not peel during processing. Controlling bonding at high temperatures, which can control the bonding energy between the bonding surfaces of thin and thin sheets.

  In addition, the present inventors have used surface modification layer 30, optionally with treatment of the bonding surface, to control the controlled bonding area, i.e., article 2, into FPD type processes (vacuum and wet processes). Provides a sufficient room temperature bond between the thin sheet 20 and the carrier 10 so that the article 2 can be processed at high temperature, for example, after finishing the high temperature processing, eg, FPD type processing or LTPS processing. The covalent bond between the thin sheet 20 and the carrier 10 is controlled so that the sheet 20 can be removed from the carrier 10 (at least without damaging the thin sheet, and preferably without damaging the carrier) ( It has been discovered that the above concepts can be balanced to easily achieve the bonding area (even at high temperatures above 400 ° C.). A series of tests were used to evaluate potential bonding surface treatments and surface modified layers that would provide a reusable carrier suitable for FPD processing. Although the different FPD fields have different requirements, the LTPS and oxide TFT processes appear to be the most demanding at this point, and therefore, since these processes are desirable applications for article 2, the steps in these processes are Representative tests were selected. Vacuum processes, wet cleaning (including SRD and ultrasonic type processes) and wet etching are common to many FPD fields. Typical aSi TFT fabrication requires processing up to 320 ° C. In the oxide TFT process, annealing at 400 ° C. is used, whereas in LTPS processing, a crystallization step and a dopant activation step exceeding 600 ° C. are used. Thus, while certain bonding surface treatments and surface modification layers 30 can keep the thin sheet 20 bonded to the carrier 10 during FPD processing, such processing (including processing at temperatures above 400 ° C.) The following five tests were used to assess the tendency of the thin sheet 20 to be later removable from the carrier 10 (without damaging the thin sheet 20 and / or the carrier 10). The tests were performed in sequence and the samples proceeded from one test to the next unless there was a type of failure that would not allow subsequent tests.

  (1) Vacuum test. Vacuum compatibility testing was performed in an STS Multiplex PECVD load lock (obtained from SPTS, Newport, UK)-this load lock was an Ebara A10S dry pump with a soft pump valve (Sacramento, CA). (Obtained from Ebara Technologies Inc., Inc.). The sample was placed in a load lock and then the load lock was aspirated from atmospheric pressure to 70 millitorr (about 9.3 Pa) in 45 seconds. (A) Loss of adhesion between the carrier and the thin sheet (a visual inspection with the naked eye considered that a failure occurred if the thin sheet came off or partially peeled off the carrier); b) Bubble formation between the carrier and the thin sheet (determined by visual inspection with the naked eye-samples were photographed before and after processing and then compared, if the size of the defect increased in macroscopic dimensions, Or (c) movement of the thin sheet relative to the carrier (determined by visual observation with the naked eye-samples were photographed before and after the test, and adhesive defects such as air bubbles were displaced, or edges were If it was peeled off or a thin sheet moved on the carrier, it was considered that a defect occurred), and the failure indicated by the notation “F” in the “Vacuum” column of the following table. It was thought to have become. In the table below, the notation "P" in the "Vacuum" column indicates that the sample was not disabled by the criteria described above.

  (2) Wet process test. Wet process suitability tests were performed using Semitool model SRD-470S (obtained from Applied Materials, Santa Clara, CA). The test was a 60 second rinse at 500 rpm, a Q rinse to 15 MΩcm at 500 rpm, a purge at 500 rpm for 10 seconds, a drying at 1800 rpm for 90 seconds, and a 2400 rpm under a warm nitrogen flow for 180 seconds. Consisted of drying. (A) Loss of adhesion between the carrier and the thin sheet (a visual inspection with the naked eye considered that a failure occurred if the thin sheet came off or partially peeled off the carrier); b) Bubble formation between the carrier and the thin sheet (determined by visual inspection with the naked eye-samples were photographed before and after processing and then compared, if the size of the defect increased in macroscopic dimensions, Or (c) movement of the thin sheet relative to the carrier (determined by visual observation with the naked eye-samples were photographed before and after the test, and adhesive defects such as air bubbles were displaced, or edges were If peeled or the thin sheet moved on the carrier, it was considered that a defect occurred); or (d) water permeation under the thin sheet (by a 50 × optical microscope) Determined by visual inspection, if liquid or residue could be observed, it was determined that a defect occurred), and it was considered impossible by the notation of "F" in the column of "SRD" in the table below Was. In the table below, the notation "P" in the "Vacuum" column indicates that the sample was not disabled by the criteria described above.

  (3) Temperature test up to 400 ° C. Suitability testing of the 400 ° C. process was performed using Alwin21 Accuthermo 610 RTP (obtained from Alwin21, Santa Clara, Calif.). The carrier to which the thin sheet was bonded was heated in a bath from room temperature to 400 ° C. at 6.2 ° C./min, held at 400 ° C. for 600 seconds, and cooled to 300 ° C. at 1 ° C./min. The carrier and the thin sheet were then cooled to room temperature. (A) Loss of adhesion between the carrier and the thin sheet (a visual inspection with the naked eye considered that a failure occurred if the thin sheet peeled off or partially separated from the carrier); b) Bubble formation between the carrier and the thin sheet (determined by visual inspection with the naked eye-samples were photographed before and after processing and then compared, if the size of the defect increased in macroscopic dimensions, Or (c) increased adhesion between the carrier and the thin sheet, such increased adhesion may cause peeling of the thin sheet from the carrier without damaging the thin sheet or the carrier. Hindered (by insertion of a razor blade between the thin sheet and the carrier, and / or to the thin sheet with Kapton ™ tape (Sain, Husic, NY) One inch (approximately 2.5 cm) wide x 6 inches (approximately 15 cm) attached to a piece of 2-3 inch (approximately 5-7.5 cm) a piece of thin glass of 100 square millimeters (K102 series from Gobain Performance Plastic) Long) and pulling the tape), if you attempt to separate the thin sheets or carriers, if they are damaged or any of the peeling methods, the thin sheets and carriers will When peeling was not possible, it was considered that a defect occurred: in some cases, it was considered impossible due to the notation “F” in the column of “400 ° C.” in the table below. Moreover, after bonding the thin sheet to the carrier and prior to thermal cycling, a representative sample is subjected to a peel test to ensure that certain materials, including any associated surface treatments, are thin prior to thermal cycling. It was determined that the sheet could be released from the carrier. In the table below, the notation "P" in the column "400 ° C" indicates that the sample was not disabled by the criteria described above.

  (4) Temperature test up to 600 ° C. The suitability test of the 600 ° C. process was performed using Alwin21 Accuthermo610 RTP. The carrier with the thin sheet was heated in a bath from room temperature to 600 ° C. at 9.5 ° C./min, held at 600 ° C. for 600 seconds and cooled to 300 ° C. at 1 ° C./min. The carrier and the thin sheet were then cooled to room temperature. (A) Loss of adhesion between the carrier and the thin sheet (a visual inspection with the naked eye considered that a failure occurred if the thin sheet came off or partially peeled off the carrier); b) Bubble formation between the carrier and the thin sheet (determined by visual inspection with the naked eye-samples were photographed before and after processing and then compared, if the size of the defect increased in macroscopic dimensions, Or (c) increased adhesion between the carrier and the thin sheet, delamination of the thin sheet from the carrier without damaging the thin sheet or the carrier due to such increased adhesion. (By inserting a razor blade between the thin sheet and the carrier, and / or sticking a piece of the above-mentioned "Kapton" tape to the thin sheet and pulling the tape If the thin sheet or carrier was damaged when attempting to separate the thin sheet or carrier, or if the thin sheet or carrier could not be peeled by any of the peeling methods, a problem occurred. Considered: If there was, it was considered impossible to be represented by the notation of "F" in the column of "600 ° C" in the table below. Moreover, after bonding the thin sheet to the carrier and prior to thermal cycling, a representative sample is subjected to a peel test to ensure that certain materials, including any associated surface treatments, are thin prior to thermal cycling. It was determined that the sheet could be released from the carrier. In the table below, the notation "P" in the column "600 ° C" indicates that the sample was not disabled by the criteria described above.

  (5) Ultrasonic test. Ultrasonic compatibility testing was performed by washing the articles in a four tank line. Here, the articles were processed in each of the consecutive tanks # 1 to # 4. The tank dimensions for each of the four tanks were 18.4 inches (about 47 cm) long x 10 inches (about 25 cm) wide x 15 inches (about 38 cm) deep. The two wash tanks (# 1 and # 2) contained 1% Semiclean KG obtained from Yokohama Yushi Kogyo Co., Ltd., Yokohama, Japan in 50 ° C. deionized water. Wash tank # 1 was agitated by a NEY prosonik 2 104 kHz ultrasonic generator (obtained from Blackstone-NEY Ultrasonics, Jamestown, NY), and wash tank # 2 was also agitated by a NEY prosonik 2 104 kHz ultrasonic generator. Stirred. The two rinse tanks (Tank # 3 and Tank # 4) contained 50 ° C. deionized water. Wash tank # 3 was stirred with a NEY sweepsonik 2D 72 kHz ultrasonic generator, and wash tank # 4 was stirred with a NEY sweepsonik 2D 104 kHz ultrasonic generator. The process was performed for 10 minutes in each of tanks # 1-4, after which samples were removed from tank # 4 and then spin rinsed dry (SRD). (A) Loss of adhesion between the carrier and the thin sheet (a visual inspection with the naked eye considered that a failure occurred if the thin sheet peeled off or partially separated from the carrier); b) Bubble formation between the carrier and the thin sheet (determined by visual inspection with the naked eye-samples were photographed before and after processing and then compared, if the size of the defect increased in macroscopic dimensions, Or (c) formation of other gross defects (determined by visual inspection with a light microscope at 50 × magnification, particles not previously observed between the thin glass and the carrier) Was considered defective if trapped); or (d) water penetration under a thin sheet (determined by visual inspection with a 50x optical microscope, if liquid or residue could be observed, (It was determined to have occurred), it was considered unacceptable as indicated by the notation "F" in the "Ultrasonic" column of the table below. In the table below, the notation "P" in the column "Ultrasonics" indicates that the sample was not disabled by the criteria described above. Moreover, in the table below, a blank in the "Ultrasonic" column indicates that the sample was not tested in this manner.

Binding energy test Binding energy is the energy that is required to separate a thin sheet from a carrier. Binding energy may be measured in a variety of different ways. However, as used herein, the binding energy was measured as follows.

Binding energy was measured using the double cantilever method (also known as the wedge method). In this method, a wedge of known thickness is placed at an angle between the bonded thin sheet and the carrier glass. The wedge creates a feature separation distance L. This peel distance is measured and used to calculate the binding energy γ _BE of Equation 6:

The Young's modulus E for both the carrier (1) and the thin sheet (2) of the EXG composition was 73.6 GPa. The typical thickness t _s1 of the carrier was 0.7 mm, and the thickness t _s2 of the thin sheet was 0.13 mm. The wedge having a thickness of t _w of 95 .mu.m, were used blade Martor 37,010.20 razor. Samples with very high binding energy were pre-broken with another wedge. This facilitated the insertion of the wedge and the formation of the feature peel length. For the reported binding energy data, a value of 2500 represents a test limit condition, and for that particular sample, indicates that the thin sheet could not be peeled from the carrier.

The treated surface 2 of the bonding surface through hydroxyl reduction by heating can successfully undergo FPD processing (i.e., the thin sheet 20 remains bonded to the support 10 during processing, but is still supported after processing including high temperature processing). The benefit of modifying one or more of the bonding surfaces 14, 24 with the surface modification layer 30 is that the glass carrier 10 without the surface modification layer 30 and the article 2 with the thin glass sheet 20 Was indicated by processing. Specifically, first, treatment of the bonding surfaces 14, 24 without the surface modification layer 30, but by heating to reduce hydroxyl groups was attempted. The carrier 10 and the thin sheet 20 were washed, the bonding surfaces 14 and 24 were bonded together, and then the article 2 was tested. A typical cleaning process for treating the glass for bonding involves diluting the glass with dilute hydrogen peroxide and a base (usually ammonium hydroxide, but a tetramethylammonium hydroxide solution such as JT Baker JTB-100). Or JTB-111 may also be used). Washing removes particles from the binding surface and gives an indication of surface energy, ie a measure of surface energy. The type of cleaning need not be SC1 in the cleaning mode, and other types of cleaning may be used, as the type of cleaning appears to have minimal effect on the silanol groups on the surface. The results of various tests are set forth in Table 1 below.

  Strong, but separable, initial room temperature bonds, or Van der Waals and / or hydrogen bonds, were each determined by Eagle XG® display glass (average obtained from Corning Incorporated, Corning, NY). A thin glass sheet of 100 square mm × 100 μm thick, composed of a non-alkali aluminoborosilicate glass having a surface roughness Ra of about 0.2 nm, and a single sheet of 150 mm diameter having a thickness of 0.50 or 0.63 mm. -Generated by simply cleaning the glass carrier of a single mean flat (SMF) wafer. In this example, the glass was washed in a 65: 1 bath of 40: 1: 2 deionized water: JTB-111: hydrogen peroxide for 10 minutes. The thin glass or glass support may or may not have been annealed in nitrogen at 400 ° C. for 10 minutes to remove residual water—the “support” column or “thin glass” in Table 1 below. The notation “400 ° C.” in the “” column indicates that the sample was annealed at 400 ° C. for 10 minutes in nitrogen. FPD process compatibility testing shows that this SC1-SC1 initial, room temperature, bond is mechanically strong enough to pass vacuum, SRD and ultrasonic tests. However, heating above 400 ° C. formed a permanent bond between the thin glass and the carrier, i.e., the thin glass sheet could be damaged without damaging either or both of the thin glass sheet and the carrier. , Could not be removed from the carrier. And this was so even for Example 1c, where an annealing step was performed on each of the support and the thin glass to reduce the concentration of surface hydroxyls. Thus, the above-described treatment of the bonding surfaces 14, 24 by heating alone, and then the bonding of the carrier 10 and the thin sheet 20 without the use of the surface modification layer 30, is adequately controlled for FPD processes where the temperature is above 400 ° C. Not a combined.

Treatment of the bonding surface with a hydroxyl-reducing and surface-modifying layer The hydroxyl-reducing and surface-modifying layer 30 may be used together, such as by heat treatment, to control the interaction of the bonding surfaces 14,24. Good. For example, the binding energies of the binding surfaces 14, 24 (both van der Waals and / or hydrogen bonding at room temperature due to the polar / dispersive energy component, and covalent bonding at elevated temperatures due to the covalent energy component) are such that the binding at room temperature is It can be controlled to provide a variety of bond strengths, from difficult strength to-after high temperature processing-to prevent separating surfaces without damage. In some applications, the bonding is very weak or not at all (if the surface is in the “non-bonded” area, the “non-bonded” area is described in the thin sheet / carrier concept of US Pat. Would be desirable). In other applications, for example, when providing a reusable carrier for an FPD process or the like (which may be at or above 500 ° C, or at process temperatures of up to 600 ° C and up to 650 ° C), the thin sheet and It is desirable to have van der Waals and / or hydrogen bonding at room temperature sufficient to attach the carriers together, yet prevent or limit covalent bonding at elevated temperatures. For still other applications, the thin sheet and the carrier initially have enough bonding at room temperature to attach them together and produce strong covalent bonds at elevated temperatures (if the surface is within the "bonding region", It may be desirable for the “bonding region” to be described in the thin sheet / carrier concept of US Pat. While not intending to be bound by theory, in some cases, a surface modifying layer may be used to control the bonding at room temperature by which the thin sheet and carrier are initially attached to each other, Reduction of hydroxyl groups on the surface (eg, by heating the surface or by reacting the hydroxyl groups with a surface modified layer) may be used to control covalent bonding, particularly at elevated temperatures.

The material of the surface-modifying layer 30 can provide energy (eg, less than 40 mJ / m ² , including energy, polarity, and dispersive components, measured on a single surface) that causes the surface to form only weakly bonded surfaces 14, 24. Will give to. In one example, hexamethyldisilazane (HMDS) may be used to form this low energy surface by reacting with surface hydroxyls, leaving a trimethylsilyl (TMS) terminated surface. HMDS as a surface modification layer may be used with surface heating to reduce hydroxyl concentration to control both room and high temperature bonding. By selecting an appropriate bonding surface treatment for each bonding surface 14, 24, an article having a range of capabilities can be achieved. More specifically, it is interesting to provide a reusable carrier for LTPS processing, with each of the vacuum, SRD, 400 ° C. (items a and c), and 600 ° C. (items a and c) processing tests. To withstand (pass), a proper bond between the thin glass sheet 20 and the glass carrier 10 can be achieved.

  In one example, SC1 cleaning of both thin glass sheets and glass carriers, followed by HMDS treatment, creates a weakly bonded surface that can bind at room temperature due to van der Waals (and / or hydrogen bonding) forces. difficult. A mechanical force is applied to bind the thin glass to the carrier. As shown in Example 2a of Table 2, this binding indicates that carrier warpage has been observed in vacuum tests and SRD processing, and in the 400 ° C. and 600 ° C. thermal processes, bubbling (due to outgassing). Are observed, and the granular defects are weak enough to be observed after sonication.

In another example, the HMDS treatment of only one surface (the carrier in the example mentioned) results in a stronger room temperature deposition that withstands vacuum and SRD treatments. However, due to the thermal process above 400 ° C., the thin glass was permanently bonded to the carrier. For a hydroxyl concentration of 4.6-4.9 / nm ² for fully hydroxylated silica, the maximum surface coverage of trimethylsilyl groups on silica was 2.8 / nm ² Sindorf and Maciel in J. Phys. Chem. 1982, 86, 5208-5219, and 2.7 / nm ² as determined by Suratwala et. Al. In Journal of Non-Crystalline Solids 316 (2003) 349-363, This is not unexpected. That is, the trimethylsilyl group binds to some surface hydroxyls, but leaves some unbound hydroxyls. Therefore, given a given sufficient time and temperature, condensation of surface silanol groups that will permanently bind the thin glass and carrier will be expected.

  By heating the glass surface to reduce the surface hydroxyl concentration prior to HMDS exposure, a modified surface energy can be created and the polar component of the surface energy can be increased. Both reduce the driving force for forming covalent Si-O-Si bonds at high temperatures, resulting in stronger room temperature bonds, such as van der Waals (and / or hydrogen) bonds. FIG. 4 shows the surface energy of the “Eagle XG” display glass after annealing and after HMDS treatment. The elevated annealing temperature before HMDS exposure increases the total (polar and dispersive) surface energy after HMDS exposure (line 402) by increasing the polar contribution (line 404). It can also be seen that the variance contribution to total surface energy (line 406) remains largely unchanged by the heat treatment. While not intending to be bound by theory, the polar component of energy at the surface after HMDS treatment, and thus the increase in total energy, may be somewhat even after HMDS treatment due to the TMS coverage of the sub-monolayer by HMDS. This seems to be due to the exposed glass surface area.

  In Example 2b, a thin glass sheet was heated at a temperature of 150 ° C. in a vacuum for one hour before bonding with a non-heat treated carrier with a coating of HMDS. This heat treatment of the thin glass sheet was not sufficient to prevent the thin glass sheet from permanently bonding to the carrier at temperatures above 400 ° C.

  As shown in Examples 2c-2e of Table 2, changing the annealing temperature of the glass surface prior to HMDS exposure changes the binding energy of the glass surface to control the bond between the glass carrier and the thin glass sheet. be able to.

  In Example 2c, the support was annealed at 190 ° C. in vacuum for 1 hour, followed by HMDS exposure to provide a surface modified layer 30. In addition, the thin glass sheet was annealed at 450 ° C. in vacuum for 1 hour before bonding with the carrier. The resulting article survived the vacuum, SRD, and 400 ° C tests (items a and c, but did not pass item b due to increased foaming), but at 600 ° C. Was impossible. Thus, compared to Example 2b, the resistance to high temperature bonding was increased, but this was not sufficient to produce an article for processing above 600 ° C. (eg LTPS processing) where the carrier could be reused. Was.

  In Example 2d, the support was annealed at a temperature of 340 ° C. in vacuum for 1 hour, followed by HMDS exposure to provide a surface modified layer 30. The stacked, thin glass sheets were annealed at 450 ° C. in vacuum for 1 hour before bonding to the carrier. The results are similar to those of 2c, with the article withstanding vacuum, SRD, and 400 ° C. tests (items a and c, but did not pass item b due to increased bubble generation). However, the test at 600 ° C. was not possible.

  As shown in Example 2e, both the thin glass and the carrier were annealed at 450 ° C. in a vacuum for one hour, after which the carrier was exposed to HMDS, and then the carrier and the thin glass sheet were permanently bonded. The temperature resistance to poor bonding is improved. Annealing both surfaces to 450 ° C. prevents permanent bonding after an RTP anneal at 600 ° C. for 10 minutes, ie, this sample passed the 600 ° C. processing test (items a and c, but , Did not pass item b due to increased bubble generation; similar results were seen for the 400 ° C. test).

  In the previous examples 2a to 2e, each of the carrier and the thin sheet was “Eagle XG” glass, the carrier was a 630 micrometer thick, 150 mm diameter SMF wafer, and the thin sheet was 100 square mm × It was 100 micrometers thick. HMDS was applied by pulse deposition in a YES-5 HMDS oven (obtained from Yield Engineering Systems, San Jose, CA) and was 1 atomic layer thick (ie, about 0.2 to 1 nm). The surface coverage will be less than one monolayer, ie, some of the surface hydroxyls are not covered by HMDS, as indicated by Maciel and discussed above. Due to the small thickness of the surface modification layer, there is little risk of outgassing that can cause contamination in device fabrication. Also, as shown in Table 2 by the designation "SC1", each of the carrier and the thin sheet was cleaned using the SC1 process prior to heat treatment or any subsequent HMDS treatment.

  Comparing Example 2a with Example 2b shows that the binding energy between the thin sheet and the carrier can be controlled by changing the number of surfaces including the surface modification layer. The control of the binding energy can then be used to control the binding force between the two binding surfaces. The comparison of Examples 2b-2e also shows that the binding energy of the surface can be controlled by changing the parameters of the heat treatment applied to the binding surface before application of the surface modification layer. Again, heat treatment can be used to reduce the number of surface hydroxyls and control the degree of covalent bonding, especially at elevated temperatures.

Other materials that will function in different ways to control the surface energy on the bonding surface are used in the surface modification layer 30 to control the room temperature and high temperature bonding forces between the two surfaces. May be. For example, one or both binding surfaces may cover a chemical species, e.g., hydroxyl, or prevent steric hindrance surface modification to prevent the formation of strong permanent covalent bonds between the carrier and the thin sheet at elevated temperatures. Reusable carriers can also be made if the bed is modified to create a modest binding force. One method for creating a tunable surface energy and preventing the formation of covalent bonds over surface hydroxyls is the deposition of a plasma polymer film, for example, a fluoropolymer film. Plasma polymerization, the feed gas, e.g., carbon fluoride source _{(CF 4, CHF 3, C} 2 F 6, C 3 F 6, C 2 F 2, CH 3 F, C 4 F 8, chlorofluorocarbon or hydrochloroplatinic, Fluorocarbons), hydrocarbons such as alkanes (including methane, ethane, propane, butane), alkenes (including ethylene and propylene), alkynes (including acetylene), and aromatic compounds (including benzene and toluene) , Hydrogen, and other gas sources, such as plasma excitation at atmospheric or reduced pressure from SF ₆ (DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF (Plasma) to deposit a polymer film. Plasma polymerization produces a layer of highly crosslinked material. Control of reaction conditions and feed gas can be used to control the chemistry for tailoring film thickness, density, and functionality to the desired application.

FIG. 5 shows the complete (polymer 502) of a plasma polymerized fluoropolymer (PPFP) film deposited from a CF ₄ —C ₄ F ₈ mixture with an Oxford ICP380 etching instrument (obtained from Oxford Instruments, Oxfordshire, UK). The surface energies (including the polarity (line 504) and dispersion (line 506) components) are shown. The films were deposited on sheets of "Eagle XG" glass and spectroscopic ellipsometry showed that the films were 1-10 nm thick. As can be seen from FIG. 5, glass supports treated with plasma polymerized fluoropolymer membranes containing less than 40% C ₄ F ₈ show surface energies of more than 40 mJ / m ² and have room temperature due to van der Waals or hydrogen bonding. Produces a controlled bond between the thin glass and the carrier. Upon initial bonding of the carrier and the thin glass at room temperature, enhanced binding is observed. That is, when the thin sheets are placed on a carrier and pressed together at some point, at a slower rate than observed for the SC1-treated surface, without the surface modified layer thereon, The wavefront moves across the carrier. This controlled bond is sufficient to withstand all standard FPD processes, including vacuum, wet, ultrasonic, and thermal processes up to 600 ° C., ie, the controlled bond is thin from the carrier The glass passed the 600 ° C. treatment test without any movement or delamination. Peeling was accomplished by razor blade and / or peeling with "Kapton" tape, as described above. The process compatibility of two different PPFP films (deposited as described above) is shown in Table 3. PPFP1 of Example 3a was formed with C ₄ F ₈ / (C ₄ F ₈ + CF ₄ ) = 0, that is, formed of CF ₄ / H ₂ instead of C ₄ F ₈ , and PPFP ₂ of Example 3b was formed of C deposited at _{4 F 8 / (C 4 F} 8 + CF 4) = 0.38. Both types of PPFP films survived vacuum, SRD, 400 ° C. and 600 ° C. processing tests. However, delamination is observed after ultrasonic cleaning of PPFP2 for 20 minutes, indicating insufficient adhesion to withstand such treatment. Nevertheless, a surface modified layer of PPFP2 may be useful for certain applications, such as when sonication is not required.

  In examples 3a and 3b above, each of the carrier and the thin sheet was "Eagle XG" glass, the carrier was a 630 micrometer thick, 150 mm diameter SMF wafer, and the thin sheet was 100 square mm x It was 100 micrometers thick. Due to the small thickness of the surface modification layer, there is little risk of outgassing that can cause contamination in device fabrication. Furthermore, the risk of outgassing is further reduced, as the surface-modified layer did not appear to degrade. Also, as shown in Table 3, each of the thin sheets was cleaned using the SC1 process before heat treatment at 150 ° C. for 1 hour in vacuum.

Still other materials that will function in different ways to control surface energy may also be used as a surface modification layer to control room and high temperature bonding forces between thin sheets and carriers. Good. For example, a bonding surface capable of producing a controlled bond can be formed by silanizing a glass carrier and / or a thin sheet of glass. The silane is selected to produce a suitable surface energy and to have sufficient thermal stability for the application. Carrier or thin glass to be processed, silane would interfere from reacting with the surface silanol groups organic material and other impurities (e.g., metal) in order to remove, a process, for example, O ₂ plasma or It may be washed with UV-ozone and SC1 or Standard Clean 2 (known in the art as SC2). Cleaning solution based on other chemicals, for example, it may be used HF, or H ₂ SO ₄ cleaning chemistry. The carrier or thin glass may be heated (as described above for the surface modified layer of HMDS) to control the surface hydroxyl concentration prior to application of the silane, and / or the silane condensation with the surface hydroxyl Heat may be applied after application of the silane to complete. The concentration of unreacted hydroxyl groups after the silane treatment is to prevent permanent bonding between the thin glass and the carrier at temperatures above 400 ° C., ie, to form a controlled bond, before bonding. May be low enough. This approach is described below.

Example 4a
The glass support with the bonded surface treated with O ₂ plasma and SC1 was then treated with 1% dodecyltriethoxysilane (DDTS) in toluene and annealed at 150 ° C. in vacuum for 1 hour to complete the condensation did. DDTS treated surface shows a surface energy of 45 mJ / m ^2. As shown in Table 4, a thin sheet of glass (SC1 washed and heated in vacuum at 400 ° C. for 1 hour) was bonded to the bonding surface of the carrier with the DDTS surface modified layer on it. The article survived wet and vacuum process tests, but did not survive thermal processes above 400 ° C. without forming bubbles under the carrier due to the thermal decomposition of the silane. This pyrolysis shows that all linear alkoxy and chloroalkylsilanes R1 _x Si (except for methyl, dimethyl, and trimethylsilane (x = 1 to 3, R1 = CH ₃ ) which result in a coating with good thermal stability) OR2) _y (Cl) _z (x = 1 to 3, y + z = 4-x).

Example 4b
The glass carrier with the bonding surface treated with O ₂ plasma and SC1 was then treated with 1% 3,3,3-trifluoropropyltriethoxysilane (TFTS) in toluene and 150 ° C. in vacuum for 1 hour. To complete the condensation. TFTS treated surface shows a surface energy of 47 mJ / m ^2. As shown in Table 4, a thin sheet of glass (SC1 washed and then heated in vacuum at 400 ° C. for 1 hour) was bonded to the bonding surface of the carrier with the TFTS surface modification layer on it. . This article survived vacuum, SRD, and 400 ° C. process tests without the thin sheet of glass permanently bonding to the glass carrier. However, in the 600 ° C. test, bubbles formed beneath the support due to the thermal decomposition of the silane. This was not unexpected because of the limited thermal stability of the propyl group. Although this sample was not acceptable for the 600 ° C. test due to bubble formation, the material and heat treatment of this example could tolerate bubbles and their adverse effects, such as reduced surface flatness or increased wavyness. May be used for some applications.

Example 4c
The glass carrier with the bonded surface treated with O ₂ plasma and SC1 is then treated with 1% phenyltriethoxysilane (PTS) in toluene and annealed at 200 ° C. in vacuum for 1 hour to complete the condensation did. PTS treated surface shows a surface energy of 54 mJ / m ^2. As shown in Table 4, a thin sheet of glass (SC1 washed and then heated in vacuum for 1 hour at 400 ° C.) was bonded to the bonding surface of the carrier with the PTS surface modified layer. This article survived vacuum, SRD, and thermal processes up to 600 ° C. without the thin sheet of glass permanently bonding to the glass carrier.

Example 4d
The glass carrier with the bonded surface treated with O ₂ plasma and SC1 is then treated with 1% diphenyldiethoxysilane (DPDS) in toluene and annealed at 200 ° C. in vacuum for 1 hour to complete the condensation did. DPDS treated surface shows a surface energy of 47 mJ / m ^2. As shown in Table 4, a thin sheet of glass (SC1 washed and then heated in vacuum for 1 hour at 400 ° C.) was bonded to the bonding surface of the carrier with the DPDS surface modified layer. This article survived vacuum and SRD tests and thermal processes up to 600 ° C. without the thin sheet of glass permanently bonding to the glass carrier.

Example 4e
The glass carrier with the bonded surface treated with O ₂ plasma and SC1 is then treated with 1% 4-pentafluorophenyltriethoxysilane (PFPTS) in toluene and annealed at 200 ° C. in vacuum for 1 hour. The condensation was completed. PFPTS treated surface shows a surface energy of 57mJ / m ^2. As shown in Table 4, a thin sheet of glass (SC1 washed and then heated at 400 ° C. in vacuum for 1 hour) was bonded to the bonding surface of the carrier with the PFPTS surface modified layer. This article survived vacuum and SRD tests and thermal processes up to 600 ° C. without the thin sheet of glass permanently bonding to the glass carrier.

  In the previous examples 4a to 4e, each of the carrier and the thin sheet was “Eagle XG” glass, the carrier was a 630 micrometer thick, 150 mm diameter SMF wafer, and the thin sheet was 100 square mm × It was 100 micrometers thick. The silane layer was a self-assembled monolayer (SAM) and therefore had a thickness of less than about 2 nm. In the above example, the SAM was formed using an organosilane having an aryl or alkyl non-polar tail and a mono, di, or tri-alkoxide head group. They react with the silanol surface on the glass and attach directly to the organic functional groups. The weak interaction between the non-polar head groups organizes the organic layer. Due to the small thickness of the surface modification layer, there is little risk of outgassing that can cause contamination in device fabrication. Again, the risk of outgassing is again lower as the surface modified layer did not appear to degrade in Examples 4c, 4d, and 4e. Also, as shown in Table 4, each of the thin sheets of glass was cleaned using the SC1 process before heat treatment at 400 ° C. for 1 hour in vacuum.

As can be seen from a comparison of Example 4 a to 4 e, so as to facilitate bonding at the initial room temperature, controlling the surface energy of the bonding surface so that 40 mJ / m ² greater withstands FPD processing, but still damage It is not the only consideration for forming a controlled bond that allows the thin sheet to be removed from the carrier without the need. Specifically, as can be seen from Examples 4a-4e, each carrier has a surface energy of greater than 40 mJ / m ² , which allows the initial room temperature bonding so that the article withstands vacuum and SRD processing. Promoted. However, Examples 4a and 4b did not pass the 600 ° C treatment test. As noted above, for certain applications, the bond may be heated to a high temperature (e.g., where the article is designed to be used) without degrading to a point where the bond is insufficient to hold the thin sheet and carrier together. Such high temperatures so as to withstand processing up to 400 ° C., 500 ° C. or higher, or 600 ° C. or higher up to 650 ° C. suitable for the process, and that there is no permanent bond between the thin sheet and the carrier. It is also important to control the covalent bonds that occur in As shown by the example in Table 4, aromatic silanes, and in particular, phenyl silanes, promote the initial room temperature bonding, resist FPD processing, and still allow controlled removal of thin sheets from the carrier without damage. It is useful to provide a bonded connection.

Another example of using a fluorocarbon surface modification layer and its treated plasma polymerized membrane to adjust the surface energy of the binding surface and create an alternative polar binding site thereon is a mixture of a fluorocarbon gas source. And forming a nitrogen-based polar group on the surface-modified layer by using various methods.

The surface modified layer is made of S.I. The theoretical model developed by Wu (1971) was calculated by fitting to the contact angles (CA) of three different test liquids, in this case deionized water (water), hexadecane (HD), and diiodomethane (DIM). May be formed by plasma polymerization of different mixtures of fluorocarbon gas sources to provide different surface energies, including surface energies greater than about 50 mJ / m ² (Literature: S. Wu, J. Polym Sci. C, 34, 19, 1971; hereinafter referred to as "Wu model"). A surface energy of greater than about 50 mJ / m ² on the binding surface of the support is beneficial for bonding the support to a thin glass sheet. This is because it facilitates the initial room temperature bonding of the carrier to the thin glass sheet and allows FPD processing of the carrier / thin glass sheet without delaminating them during the process. In some cases, depending on the composition and the deposition conditions of the surface modification layer, a surface modification layer having this surface energy may cause the support and the thin glass sheet to reach a temperature of up to about 600 ° C., and in some cases even higher. Even after treatment at temperature, it can be peeled off by peeling. Generally, the feed gas comprises a mixture of an etching gas and a polymer forming gas. As discussed above with respect to FIG. 5, the etching gas may be CF ₄ , while the polymer forming gas may be C ₄ F ₈ . Alternatively, as shown in FIG. 13, the etching gas may be CF ₄ , while the polymer forming gas may be CHF ₃ . As shown in both FIGS. 5 and 13, in general, the lower the proportion of polymer forming gas, the higher the total surface energy 502, 1312 of the resulting bonding surface, where the total surface energy is It is a combination of polar components 504, 1314 (triangular data points) and variance components 506, 1316 (square data points). The ratio of the polymer-forming gas (eg, CHF ₃ ) during the plasma polymerization indicates the total surface energy in mJ / m ² , by using an inert gas (eg, Ar) as shown in FIG. 13A. Would be controlled similarly to control the resulting surface energy. Without intending to be bound by theory, the inert gas may act as an etchant, diluent, or both. In any case, it is clear that the surface energy of the carrier glass can be changed only by CHF ₃ without including CF _{4 in the} gas stream. The deposition of the surface modification layer may be performed at atmospheric or reduced pressure, and may include plasma excitation, such as DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF. It is performed by plasma. The plasma polymerized surface modification layer may be deposited on a carrier, a thin sheet, or both. As mentioned earlier for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Control of reaction conditions and feed gas can be used to control the chemistry for tailoring the thickness, density, and functionality of the surface modified layer to the desired application. By controlling the properties of the film, the surface energy of the binding surface of the carrier can be adjusted. However, surface energy is only one consideration in controlling the degree of bonding.

  The degree of controlled coupling, or moderate coupling, can be further tuned by controlling the polar coupling used to achieve the desired surface energy. One method of controlling polar bonding is to subject the surface-modified layer (formed as described above) to a further treatment for incorporating a polar group, for example, treatment with a nitrogen-containing plasma. . This treatment increases the adhesion by forming nitrogenous polar functional groups on the thin surface modification layer. The nitrogen-based polar groups formed during this subsequent processing do not condense with the silanol groups to form a permanent covalent bond, and therefore are carried out to deposit a film or structure on a thin sheet. During subsequent processing, the degree of bonding between the thin sheet and the carrier can be controlled. Examples of methods for forming a nitrogen-based polar group include nitrogen plasma treatment (Examples 5b to d, k, l), ammonia plasma treatment (Examples 5e, f, h to j), and nitrogen / hydrogen plasma treatment (Example 5m). ).

It is observed that the thin glass sheets and glass carriers bonded by the surface-modified layer treated with the nitrogen-containing plasma do not adhere permanently after annealing at 600 ° C., ie, they have a temperature of 600 ° C. Pass item (c) of the test. Also, this modest bond is strong enough to withstand the FPD process (including the vacuum test (1), wet process test (2), and ultrasonic test (5) described above) and has sufficient peel force. Remains detachable by the application of. Exfoliation allows removal of devices manufactured on thin glass and reuse of the carrier. Nitrogen plasma treatment of the surface modified layer will obtain one or more of the following advantages: minimal bubble defects after initial bonding, resulting in strong adhesion between the thin sheet and the carrier; High surface energy and low water contact angle (see Examples 5b-f and i-1); reduced defect formation when heat treated due to the improved thermal stability of the surface modified layer (Example 5c, 5d, 5k, 5l, i.e., the sample treated with N ₂ is visually observed, showed reduced bubble formation); and and / or formation of a surface modification layer by the separation process, the carrier / surface modification Easier process windows (Examples 5f-f and h-m) as different processes are possible to optimize the quality layer as well as the surface modification layer / thin glass interface. That is, the base material of the surface modification layer itself and the deposition process will be devised to optimize the interaction between the surface modification layer and the binding surface of the support. Then, alternatively, after depositing the surface-modifying layer on the carrier, the properties of the surface-modifying layer may be used to optimize the interaction of the surface-modifying layer with the thin sheet to be placed thereon. It may be changed by processing.

In the examples in Table 5 below, various conditions were used to deposit a plasma polymerized film on a glass carrier. The glass carrier was a substrate manufactured from Corning® “Eagle XG” (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to deposition of the surface modification layer, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques. The films were deposited in an Oxford Plasmalab 380 inductively coupled plasma (ICP) system equipped with a 13.56 MHz RF source for both the coil and platen, with the platen temperature fixed at 30 ° C. Samples 5a-5j were subjected to nitrogen and ammonia plasma treatment of the surface modified layers in an STS Multiplex PECVD apparatus in triode electrode placement mode (obtained from SPTS, Newport, UK). A carrier is placed on a platen heated to 200 ° C., to which a specific wattage of 380 kHz RF energy is applied, and a showerhead is placed on the platen, which is then provided with a specific wattage of 13.5 MHz RF energy. Was applied. For the energy applied to both the Oxford ICP and the STS PECVD, the numbers are shown as # / # W, where the number before the slash is applied to the top electrode (coil on ICP or showerhead on PECVD). The number after the slash is the wattage applied to the platen. If only one number is shown, this is for the top electrode. Gas flow rates into the vessel were as shown in Table 5 (flow rates are cubic centimeters per minute-sccm per minute under standard conditions). Thus, for example, the notation in the "Surface treatment" column of Table 5 for Example 5g reads as follows: In an Oxford ICP apparatus, 30 sccm CF in a 5 mtorr (about 0.67 Pa) pressure vessel. ₄ , 10 sccm of C ₄ F ₈ , and 20 sccm of H ₂ were co-flushed; 1000 W of 13.5 MHz RF energy was applied to the coil and 50 W of 13.56 MHz RF energy was placed on the carrier. Was applied to the platen at 30 ° C .; the deposition time was 60 seconds. The column notation for surface treatment for the remaining examples can be read as well. As yet another example, in the column "Plasma treatment", the notation for the treatment of Example 5h can be read as follows: After forming the surface modified layer by the parameters of the surface treatment column of Example 5h, 100 sccm NH ₃ is supplied to a STS PECVD bath at a pressure of 1 Torr and a temperature of 200 ° C .; 13.56 MHz of 100 W is applied to the showerhead; the process is carried out for 30 seconds. The notation in the column “Plasma treatment” for the remaining examples can be read similarly. The surface energies of both polar and dispersed components fit the Wu model to the contact angles (CA) of three different test liquids, in this case deionized water (water), hexadecane (HD), and diiodomethane (DIM). Was calculated in mJ / m ² (millijoules per square meter). For the surface energies, the polarity (P) and dispersion (D) components and the total (T) are shown.

  In Examples 5b to 5f and 5h to 5l in Table 5, a nitrogen-based polar group is formed on the surface-modified layer. Here, these polar groups are strong enough to withstand FPD processing, but weak enough to allow for exfoliation, to form a temporary bond with the carrier and a thin sheet (eg, a glass carrier and (A thin sheet of glass). After the treatment, the concentration of the polar group on the surface of the surface modified layer is higher than the concentration inside the surface modified layer.

Example of treatment with NH ₃ plasma (5e, f, and h to j)
Moderate surface energy SML from a 30 sccm CF ₄ , 10 sccm C ₄ F ₈ , 20 sccm H ₂ ICP plasma system at 5 mTorr with a 1500 W coil and 50 W platen RF power. (Control example 5a) and another with a 1000 W coil and 50 W platen RF power at 5 mtorr (about 0.67 Pa), 30 sccm CF ₄ , 10 sccm C ₄ F ₈ , 20 sccm the deposited from H ₂ (control example 5 g). The surface energy of the untreated fluoropolymer membrane is shown in Table 5. The samples were transferred to an STS PECVD system and exposed to an ammonia plasma under the conditions listed in Table 5 (Examples 5e, 5f, 5h-j). The surface tension was measured with deionized water and hexadecane by the formula Wu, depending on the ammonia plasma conditions, it increased from about 40 to about 65~80mJ / m ^2. A thin glass sheet was bonded to each of these NH ₃ plasma modified samples. After the temperature test at 600 ° C., little change was observed visually in the cell area (no formal outgassing test was performed), and in all of these samples the thin glass sheet was easily peeled off by hand.

Example of treatment with N ₂ plasma (5c, d, k, l)
Moderate surface energy SML from a 30 sccm CF ₄ , 10 sccm C ₄ F ₈ , 20 sccm H ₂ ICP plasma system at 5 mTorr with a 1500 W coil and 50 W platen RF power. (Control example 5a) and another with a 1000 W coil and 50 W platen RF power at 5 mtorr (about 0.67 Pa), 30 sccm CF ₄ , 10 sccm C ₄ F ₈ , 20 sccm the deposited from H ₂ (control example 5 g). The surface energy of the untreated fluoropolymer membrane is shown in Table 5. Samples 5c, d, k, l were N ₂ plasma treated in situ in an ICP system under the conditions listed in Table 5. The surface energy increased from about 40 to over 70 mJ / m ² depending on the ammonia plasma conditions. A thin glass sheet was bonded to each of these samples. After a temperature test at 600 ° C., the thin glass sheets of all of these samples peeled off easily by hand.

Example of simultaneous N ₂ and H ₂ plasma treatment (5m)
Moderate surface energy of the SML, the RF output of the coil and 50W platens 1000W, 5 millitorr (about 0.67 Pa) at, 30 sccm of CF _4, 10 sccm of C ₄ F _8, 20sccm ICP plasma system from of H ₂ (Control example 5 g). The surface energy of the untreated fluoropolymer membrane is shown in Table 5. Sample 5m was simultaneously subjected to in situ N ₂ + H ₂ plasma treatment in an ICP system under the conditions listed in Table 5. The surface energy was not shown to be different from the untreated fluoropolymer film.

Example of treatment with continuous N ₂ and H ₂ plasma (5b)
The SML moderate surface energy, the RF output of the platen of the coil and 50W of 1500 W, 5 mTorr (about 0.67 Pa), 30 sccm of CF _4, 10 sccm of C ₄ F _8, 20sccm ICP plasma system from of H ₂ (Control Example 5a). The surface energy of the untreated fluoropolymer membrane is shown in Table 5. The sample was then subjected to a continuous in situ N ₂ and H ₂ plasma treatment in an ICP system under the conditions listed in Table 5. The surface energy was increased to 70 mJ / m ² greater. This value is comparable to that obtained with ammonia or nitrogen plasma. A thin glass sheet was bonded to this sample and subjected to a temperature test at 600 ° C., after which the thin glass sheet could be peeled from the carrier, ie the sample passed item (c) of the 600 ° C. processing test.

  XPS data revealed the effects of ammonia and nitrogen plasma treatment on the surface modified layer. In particular, the ammonia plasma treatment approximately halves the carbon content of the surface modified layer, reduces the fluorine concentration by about 1/4, and adds about 0.4 at% nitrogen. Silicon, oxygen, and other glass components are also seen to increase, consistent with the ammonia plasma removing fluoropolymer, while adding small amounts of nitrogen species to the surface. Nitrogen plasma treatment increases the nitrogen content to 2 at%, but also reduces the content of carbon and fluorine, as well as ammonia. Silicon, oxygen and other glass components also increase consistent with a decrease in film thickness. Thus, ammonia and nitrogen plasma treatments are also shown to add polar groups to the surface modified layer, but reduce the thickness of the surface layer. The thickness as a result of the surface modification layer was generally less than 20 nm. Therefore, an effective surface modification layer generally balances the thickness of the surface modification layer with subsequent surface treatment times to achieve controlled bonding.

  As mentioned above, the thin glass sheet bonded to the carrier, as in the example of Table 5, is "Corning" Willow® Glass (Corning Incorporated, Corning, NY), which is an alkali-free aluminoborosilicate glass. And a thickness of 100, 130, and 150 micrometers. Prior to bonding, the "Will" Glass was cleaned using an oxygen plasma followed by SC1 and / or SC2 chemistry and standard cleaning techniques.

  In the example of Table 5, the bonding surface on which the surface modification layer was disposed was glass, but need not be. Alternatively, the bonding surface may be another suitable material having similar surface energies and properties as glass, for example, silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

  The use of a plasma polymerized fluoropolymer surface modification layer having a thickness of less than 20 nm to control the bonding energy of the glass bonding surface was demonstrated in the examples of Tables 3 and 5. The initial bonding of a thin sheet of glass to such a glass carrier with a surface-modifying layer on it resembles the bonding of glass to glass: a strong attractive force between the thin sheet and the coated glass carrier. Due to the interaction, the coupling front moves rapidly. The physical cause of this attractive interaction is whether the polar groups on the thin glass sheet (mainly silanol groups) and the polar groups on the surface modified layer of the support, with or without hydrogen-bonded molecular water. It is an interaction between dipoles (Kesom). However, the fluoropolymer surface modification treatment prevents the thin sheet from permanently bonding to the carrier at temperatures up to 600 ° C. associated with device fabrication. To provide an overwhelming cost advantage to the low yield acid thinning of thicker glass, the carrier needs to be recycled. This is a concern when using a fluorinated surface modification layer since the fluoropolymer deposition process etches the surface of the carrier. Reuse of carriers with their surface modified layers has been shown, but the surface roughness increases from 0.3 nm to about 1.2 nm Ra. This increase in roughness reduces carrier binding by reducing binding energy (on the carrier recycled after deposition, removal, and redeposition of the surface-modifying layer), thereby reducing carrier recycling. Can affect the possibilities. Also, increased surface roughness may limit reuse of the carrier in other applications, such as using the carrier itself as a display substrate, by not meeting the new glass roughness specifications. It was also observed that after annealing the bonded pair of thin glass sheet and carrier at a temperature above 300 ° C., roughness was introduced on the bonded surface side of the thin glass sheet. The increased roughness on the bonding surface of the thin sheet may be due to the etching of the bonding surface of the thin glass by fluorine-containing gas desorbed from the bonding surface of the surface-modified layer treated carrier. In some cases, this increase in roughness of the bonding surface is not necessary. In other cases, the increase in roughness is small, but this may not be acceptable, as this increase may limit, for example, carrier recycling. Moreover, there may be undesirable reasons for using fluorinated gases in certain manufacturing operations, for example, health and safety reasons.

In this way, a thin sheet can be separated from the carrier without damaging, but strong enough to withstand controlled bonding, ie, FPD processing (high temperature processing, for example at temperatures above 400 ° C. or 600 ° C.). Using an alternative polar bond to form a bond (even after processing), sufficient surface energy (eg, greater than 50 mJ / m ² , as discussed above with respect to the examples in Table 5) It may be desirable to form. Accordingly, the inventors of the present application have investigated alternative methods of forming a suitable polar bond that can be used to controlly bond a thin sheet to a carrier.

The present inventors have studied the use of hydrocarbon polymers, or more generally, carbonaceous layers, where little or no fluorine is utilized to etch the glass. However, several important challenges had to be overcome. The surface energy of the carbonaceous layer, the carbonaceous layer is to bond the glass must be about 50 mJ / m ² greater. In some cases, the carbonaceous surface modification layer may provide a surface energy of 65 mJ / m ² or more to provide a bond between the thin sheet and the carrier that is strong enough to withstand wet processing without liquid penetration. Should have. At 65 mJ / m ² , the surface energy of the carrier (for bonding to a thin glass sheet) is sufficient to prevent liquid (eg, water) penetration between the carrier and the thin sheet during subsequent processing. . At a surface energy of about 50 mJ / m ² , bonding to a thin glass sheet will be sufficient for most FPD processing, but may require heat treatment to prevent liquid penetration. Specifically, the polar components of the hydrocarbon layer need to be increased or mediated by hydrogen-bonded molecular water to achieve strong inter-dipole bonds directly with the silanol groups of the thin glass sheet. This carbonaceous layer is thermally, chemically, and vacuum compatible so that it is at least useful for amorphous silicon (aSi) TFT, color filter (CF), or carrier / thin sheet articles that experience the manufacturing process of capacitive touch devices. Sex should be shown. This seemed possible because aliphatic hydrocarbons such as polyethylene show great thermal stability in an inert atmosphere. Unlike fluoropolymers, which can depolymerize under certain circumstances, HDPE simply burns. HDPE may burn, but if the thickness of the polymer is small enough, it can still be seen through it. The ultimate concern was that mechanical stability and wet process compatibility appeared to require higher adhesion than can be achieved by van der Waals forces alone. A binding energy of about 250 to about 275 mJ / m ² has been found to be beneficial in withstanding wet sonication on the thin sheets of glass used. This large binding energy may be due to particle and edge defects, not a fundamental requirement of the binding process. At best, bonding two clean glass surfaces can produce a binding energy of about 150 mJ / m ² . To achieve the bond strength 250~275mJ / m ² requires a certain amount of covalent bonds.

The surface modified layers studied in the examples of Tables 6-12 are organic layers based on a fluorine-free material source. As explained in more detail below, an amorphous hydrocarbon layer (or simply a carbonaceous layer) could be produced on a glass support (Table 6), but the surface energy was clean enough to withstand the FPD process. It did not produce sufficient adhesion to the glass surface. This was not surprising since organic surface modified layers based on methane and hydrogen did not contain strong polar groups. To increase the polar groups available for bonding to thin glass sheets, additional gas could be added during plasma polymerization to achieve sufficient surface energy (Table 7). However, in some cases, sufficient surface energy has been achieved, but this one-step process involves some complexity in obtaining a suitable mixture of material sources. Therefore, a two-step process was developed: in the first step, the surface modification layer was formed (eg, from two gases, similar to the method performed in the example of Table 6); The surface modification layer was treated in various ways to increase the polar groups and surface energy available for bonding to thin glass sheets. Although there were more steps, this process was not too complicated to manage to get the desired result. These treatments increase the polar groups on the surface of the surface modified layer that are bonded to the thin sheet. Thus, the interior of the surface modifying layer may not, in some cases, contain polar groups, but polar groups are available to bind the carbonaceous layer to a thin sheet. Various methods of treating the initial surface modification layer has been studied in the example of Table 8-12: In the example of Table 8, the surface modification layer is treated by NH _3; in the example of Table 9, the surface The modified layer is treated with N ₂ ; in the example of Table 10, the surface modified layer is successively treated with N ₂ and then with H ₂ ; in the example of Table 11, the surface modified layer is the N ₂ -O _2, and then, is continuously processed by N _2; in the example of Table 12, the surface modification layer is processed by N ₂ -O _2; in the example of an alternative that follow the table 12, surface modification layer is processed only by O _2. These examples illustrate the use of nitrogen and oxygen polar groups, but other polar groups would be possible.

Forming a carbonaceous surface modified layer with a hydrocarbon (eg, methane CH ₄ ) and, if necessary, hydrogen (eg, H ₂ ) , adjust the surface energy of the bonding surface, and use a plasma to cover it with surface hydroxyl. Another example of using polymerized membranes is surface modification from a carbon-containing gas, such as a hydrocarbon gas, such as methane, during plasma polymerization, optionally with another gas (such as hydrogen H ₂ ). This is the deposition of a thin film of a porous layer. However, in most cases, a hydrogen flow is preferred because otherwise the deposited material is graphitic, tends to be black, and has a low band gap. This is the same throughout the examples of the carbonaceous surface modification layer in Tables 6 to 12 and 16. The surface modification layer may be formed at atmospheric or reduced pressure, and is applied by plasma excitation, for example, DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. Is The plasma polymerized surface modification layer may be deposited on a carrier, a thin sheet, or both. As described above with respect to the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Using reaction conditions and feed gas control to control the film chemistry, density, and functionalities of the surface modified layer for the desired application, and to control film properties Thereby, the surface energy of the bonding surface can be adjusted. Surface energy is used to control the degree of bonding, i.e., during subsequent processing performed to deposit a film or structure on the thin sheet, a permanent covalent bond between the thin sheet and the carrier is formed. Can be adjusted to prevent.

In the examples in Table 6 below, various conditions were used to deposit a plasma polymerized film on a glass carrier. The deposition parameters studied in the example of Table 6 were: gas ratio (methane: hydrogen); pressure, ICP coil and RF bias power. The glass carrier was a substrate manufactured from "Corning""EagleXG" (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to film deposition, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques. The films were deposited in an Inductively Coupled Plasma (ICP) instrument, Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK). Here, the carrier is placed on the platen, and 13.56 MHz RF energy of a specific wattage (described in the “RF bias” column) is applied thereto, and the coil is placed on the platen, and Of wattage (described in the “coil” column) at 13.5 MHz RF energy was applied. The flow rates of the methane (CH ₄ ) source and hydrogen (H ₂ ) source into the tank were as shown in the columns for CH ₄ and H ₂ , respectively (the flow rates were Cubic centimeter-sccm). CH ₄ and H ₂ gases were flowed together. The column “H ₂ / CH ₄ ” also shows the H ₂ : CH ₄ feed gas ratio, and the column “Pressure” also shows the tank pressure (milliTorr). Thus, for example, the notation in Table 6 of Example 6a reads as follows: In an Oxford ICP apparatus, 6.7 sccm of CH ₄ and 33.3 sccm of H ₂ are applied at a pressure of 20 mtorr (about 2.67 Pa). ) Were applied together; 1500 W of 13.5 MHz RF energy was applied to the coil and 300 W of 13.56 MHz RF energy was applied to the platen on which the carrier was placed. The platen temperature was 30 ° C. for all depositions. The notation for the remaining examples can be read as well. The surface energy was measured for three different test liquids (in this case, deionized water (indicated in the “W” column), hexadecane (indicated in the “H” column), and diiodomethane (in “DIM”). Calculated in mJ / m ² (millijoules per square meter) by using the contact angle (CA) and Wu model shown in the column). For the surface energies, the polarity (P) and dispersion (D) components and the total (T) are shown.

Examples surface energy related 6a~6j varied from about 40 to about 50 mJ / m ^2. However, in general, the surface energies of these examples were less than about 50 mJ / m ² (considered to be suitable for controllably bonding the glass carrier to a thin sheet of glass). The thickness of the surface modified layer was about 6 nm. These examples did not produce sufficient adhesion between the carrier and the thin sheet to withstand FPD processing, i.e., they were observed to form bubbles during the vacuum test and during the wet process test Hot water infiltration was observed to have occurred.

  While these surface-modifying layers themselves were not suitable for bonding to thin glass sheets, they are not suitable for other applications, such as electronic or other structures on thin polymeric sheets, as described below. May be used to apply a thin sheet of polymer to a glass carrier to process the glass carrier. Alternatively, the thin sheet may be a composite sheet having a polymeric surface that may be bonded to a glass carrier. In this case, the composite sheet may comprise a glass layer on which the electrons or other structures may be deposited, whereas the polymer part forms a bonding surface for a controlled bonding with the glass carrier.

  In the example of Table 6, the bonding surface on which the surface modification layer was disposed was glass, but need not be. Alternatively, the bonding surface may be another suitable material having similar surface energies and properties as glass, for example, silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

One-Step Formation of Surface Modification Layer by Mixture of Non-Fluorinated Sources Another example of using a plasma polymerized membrane to adjust the surface energy of the bonding surface and coat it with surface hydroxyls is a carbon-containing gas, such as FIG. 4 is the deposition of a thin film of a surface modified layer from a mixture of non-fluorinated gas sources, including hydrocarbons. The deposition of the surface modification layer may be performed at atmospheric or reduced pressure and is performed by plasma excitation, for example, by DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. Is The plasma polymerized surface modification layer may be deposited on a carrier, a thin sheet, or both. As described above with respect to the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Using reaction conditions and feed gas control to control the film chemistry, density, and functionalities of the surface modified layer for the desired application, and to control film properties Thereby, the surface energy of the bonding surface can be adjusted. Surface energy is used to control the degree of bonding, i.e., during subsequent processing performed to deposit a film or structure on the thin sheet, a permanent covalent bond between the thin sheet and the carrier is formed. Can be adjusted to prevent.

In the examples in Table 7 below, various conditions were used to deposit a plasma polymerized film on a glass carrier. The glass carrier was a substrate manufactured from "Corning""EagleXG" (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to film deposition, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques. The films were deposited in an Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK) in dielectrically coupled plasma (ICP) configuration mode. Here, the carrier is placed on the platen, and 13.56 MHz RF energy of a specific wattage (described in the “RF bias” column) is applied thereto, and the coil is placed on the platen, and Of wattage (described in the “coil” column) at 13.5 MHz RF energy was applied. The flow rates of the methane (CH ₄ ), nitrogen (N ₂ ) and hydrogen (H ₂ ) feed gases into the vessel were as shown in the columns for CH ₄ , N ₂ and H ₂ respectively. (The flow rate is cubic centimeters per minute-sccm under standard conditions). CH ₄ , N ₂ and H ₂ gases were flowed together. The column “N ₂ / CH ₄ ” also shows the N ₂ : CH ₄ feed gas ratio, and the column “Pressure” also shows the tank pressure (milliTorr). Thus, for example, the notation in Table 7 of Example 7g reads as follows: In an Oxford 380 ICP apparatus, 15.4 sccm CH ₄ , 3.8 sccm N ₂ and 30.8 sccm H ₂ are pressurized. Flowed together into a 5 millitorr (about 0.67 Pa) bath; 1500 W of 13.5 MHz RF energy was applied to the showerhead and 50 W of 13.56 MHz RF energy was applied to the platen on which the carrier was placed. did. The platen temperature was 30 ° C. for all samples in Table 7. The notation for the remaining examples can be read as well. The surface energy was measured for three different test liquids (in this case, deionized water (indicated in the “W” column), hexadecane (indicated in the “H” column), and diiodomethane (in “DIM”). Calculated in mJ / m ² (millijoules per square meter) by using the contact angle (CA) and Wu model shown in the column). For the surface energies, the polarity (P) and dispersion (D) components and the total (T) are shown. In addition, the column "Thickness" shows the thickness value (in Angstroms) of the surface modified layer deposited under the conditions described for that particular example.

Example 7a shows a surface modified layer made from methane only. Under these deposition conditions, the surface modified layer formed from methane achieved only about 44 mJ / m ² surface energy on the support. While this is not at the desired level for controlled bonding of glass to glass, it may be useful for bonding the polymer binding surface to a glass carrier.

7e from example 7b is, N _2: in various proportions of CH _4, shows the methane and surface modification layer made from plasma polymerization of nitrogen. Under these deposition conditions, the surface modified layer formed from methane and nitrogen achieved a surface energy on the support from about 61 mJ / m ² (Example 7e) to about 64 mJ / m ² (Example 7d). . These surface energies are sufficient to controllably couple the thin glass sheet to the glass carrier.

Example 7f shows a surface modification layer made from plasma polymerization of methane and hydrogen (H _2). Under these deposition conditions, the surface modified layer made from methane and hydrogen achieved a surface energy of about 60 mJ / m ² on the support. This is sufficient to controllably couple the thin glass sheet to the glass carrier.

Examples 7g to 7j show surface modified layers made from plasma polymerization of methane, nitrogen, and hydrogen. Under these deposition conditions, the surface modified layer made from methane, nitrogen and hydrogen has a surface energy on the carrier from about 58 mJ / m ² (Example 7g) to about 67 mJ / m ² (Example 7j). Achieved. This is sufficient to controllably couple the thin glass sheet to the glass carrier.

  It was observed that the thin glass and carrier bonded with the surface modified layers formed according to Examples 7b to 7j did not adhere permanently after annealing at 450 ° C., ie, they had a temperature of 400 ° C. Pass item (c) of the test. Exfoliation allows for the removal of devices made on thin glass and the reuse of carriers.

  The thin glass sheets bonded to each of the carriers as in the example of Table 7 (7b to 7j) are "Corning" "Willow" Glass (Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free glass. And a thickness of 100, 130, and 150 micrometers. Prior to bonding, the "Will" Glass was cleaned using an oxygen plasma followed by SC1 and / or SC2 chemistry and standard cleaning techniques.

  In the example of Table 7, the bonding surface on which the surface modification layer was disposed was glass, but need not be. Alternatively, the bonding surface may be another suitable material having similar surface energies and properties as glass, for example, silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

The surface modified layer in the example of Table 7 is formed by a one-step process. That is, proper surface energy and polar group inclusion are achieved by depositing a surface modified layer from a selected mixture of gases under appropriate conditions. Although the proper gases and conditions have been achieved, the process involves some complexity in achieving the proper gas mixture. Therefore, a simpler process was required. It was assumed that the appropriate surface energy and appropriate polar groups could be achieved from a two-step process, where each step would be simple and stable. Specifically, in a first step, a carbonaceous surface modification layer is deposited, while in a second step, the surface modification layer is treated to increase surface energy and provide a suitable polarity for controlled bonding. It was assumed to give rise to a group. The polar groups will be more concentrated at the surface of the surface modified layer to which the thin sheet is bonded than in the bulk material. From the examples in Table 6, it was found that pressure and coil output had the greatest effect on surface energy. It was also found that the film thickness increased with increasing bias and decreasing pressure. Therefore, from these results, in order to further study the process for increasing the surface energy and including the polar group, a 20 sccm CH ₄ layer having a carbonaceous surface modified layer having a thickness of about 6.5 nm was formed. , 40 sccm H ₂ , 5 mTorr (about 0.67 Pa), 1500/50 W, and 60 seconds amorphous hydrocarbon polymer surface modification layer deposition process was selected as a starting point. Various treatments, as described in the examples of Tables 8-11, may be used to change the polar groups, and their concentrations, on the surface of the surface modification layer that binds the thin sheet to the base surface modification layer. Performed in two steps. Although specific examples of starting and treatment materials for the surface modification layer are discussed below, generally, the carbonaceous layer is formed from a carbon-containing source, and then polar groups are added by subsequent processing. Similarly, while certain polar groups are shown by way of example, other polar groups will be possible.

Another example of using a plasma polymerized membrane to adjust the surface energy of the bonding surface and create an alternative polar group binding site thereon by introducing a polar group into the carbonaceous surface modified layer by NH ₃ treatment carbon source, for example, from methane (a carbon containing gas source) and the deposition of a thin film of surface modification layer from the hydrogen H _2, followed by a nitrogen treatment of the surface modification layer just formed. The nitrogen treatment may be performed by, for example, an ammonia plasma treatment. The deposition of the surface modification layer may be performed at atmospheric or reduced pressure by plasma excitation, such as DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. . The plasma polymerized surface modification layer may be deposited on a carrier, a thin sheet, or both. As mentioned earlier for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Control of reaction conditions and feed gas can be used to control the chemistry for tailoring film thickness, density, and functional groups to the desired application, and by controlling the properties of the film, the bonding surface Surface energy can be adjusted. The nitrogen-based polar groups formed during the subsequent ammonia plasma treatment do not condense with the silanol groups to form a permanent covalent bond and therefore deposit a film or structure on a thin sheet. The degree of bonding between the thin sheet and the carrier can be controlled during subsequent processing performed on the sheet.

In the examples in Table 8 below, various conditions were used to deposit a film of the plasma polymerized surface modification layer on a glass carrier. The glass carrier was a substrate manufactured from "Corning""EagleXG" (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to film deposition, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques. The surface modification layer was deposited in an Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK) in a dielectrically coupled plasma (ICP) configuration mode. Here, the carrier is placed on a platen, and a specific wattage 13.56 MHz RF energy is applied thereto, and a coil is placed on the platen, and a specific wattage 13.5 MHz RF energy is added thereto. Was applied. More generally, for the applied energy, the number is indicated as # / # W, where the number before the slash is the wattage applied to the coil (showerhead) and the number after the slash is The wattage applied to the platen. If only one number is shown, this is for the coil. Gas flow rates into the vessel were as shown in Table 8 (flow rates are cubic centimeters per minute-sccm under standard conditions). During the plasma treatment of the surface modified layer (SML), the temperature of the layer was 30 ° C. Thus, for example, the notation in the “Surface Layer Deposition” column of Table 8 for Example 8a reads as follows: In an Oxford ICP apparatus, in a bath with a pressure of 5 millitorr (about 0.67 Pa), 40 sccm CH ₄ was poured in; 1500 W of 13.5 MHz RF energy was applied to the showerhead and 50 W of 13.56 MHz RF energy was applied to the platen on which the carrier was placed; bath temperature was 30 ° C. The deposition time was 60 seconds. The notation of the surface treatment column for the remaining examples can be read similarly, except that the surface treatment was performed in STS Multiplex PECVD (obtained from SPTS, Newport, UK). The carrier placed on the ground electrode was maintained at 200 ° C. and gas was introduced through a 13.56 MHz RF driven showerhead. As a further example, in the column "Plasma treatment", the notation of the treatment in Example 8a reads as follows: After forming the surface modification layer as the parameters in the surface layer deposition example of Example 8a, then: 100 sccm of NH ₃ is supplied to a bath at a pressure of 1 Torr (about 133 Pa) and a temperature of 200 ° C .; 300 W of 13.56 MHz RF is applied to the showerhead and the process is carried out for 60 seconds. The notation in the column “Plasma treatment” for the remaining examples can be read similarly. The surface energy was determined by using the contact angles of three different test liquids (in this case, deionized water (W), hexadecane (H), and diiodomethane (DIM)) and the Wu model, in mJ / m ² (per square meter). In millijoules). For the surface energies, the polarity (P) and dispersion (D) components and the total (T) are shown.

Examples 8a and 8b show surface modified layers of plasma polymerized hydrocarbons that were subsequently treated with a nitrogen-containing gas (ammonia). In the case of Example 8a, ammonia was used alone at a power of 300 W, whereas in Example 8b the ammonia was diluted with helium and the polymerization was carried out at a lower power of 50 W. However, in each case, sufficient surface energy was achieved on the binding surface of the carrier, which was able to controllably bind to a thin glass sheet. Examples 8c and 8d show surface modified layers of a plasma polymerized hydrocarbon formed by a hydrocarbon containing (methane) and hydrogen containing (H ₂ ) gas and subsequently treated with a nitrogen containing gas (ammonia). ing. In the case of Example 8c, the ammonia was used alone at a power of 300 W, whereas in Example 8d the ammonia was diluted with helium and the polymerization was carried out at a lower power of 50 W. It was observed that the thin glass and carrier bonded by the surface modified layer formed as in Examples 8a-8d did not adhere permanently after annealing at 450 ° C., ie, they were 400 ° C. Item (c) of the temperature test was able to withstand. Outgassing tests were not performed on these samples. Also, these examples are strong enough to withstand FPD processing (including the vacuum test (1), wet process test (2), and ultrasonic test (5) described above) and have sufficient peel force. It remained peelable on application. Exfoliation allows for the removal of devices made on thin glass and the reuse of carriers.

  The thin glass sheets bonded to each of the carriers as in the example of Table 8 were from "Corning" "Willow" Glass (obtained from Corning Incorporated, Corning, NY), which is an alkali aluminoborosilicate glass. The substrates were manufactured and had thicknesses of 100, 130, and 150 micrometers. Prior to bonding, the "Will" Glass was cleaned using an oxygen plasma followed by SC1 and / or SC2 chemistry and standard cleaning techniques.

  In the example of Table 8, the bonding surface on which the surface modification layer was disposed was glass, but need not be. Alternatively, the bonding surface may be another suitable material having similar surface energies and properties as glass, for example, silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

Another example of using a plasma polymerized membrane to adjust the surface energy of the bonding surface and create alternative polar group binding sites thereon by introducing polar groups into the carbonaceous surface modified layer by N ₂ treatment Deposition of a thin film of the surface modification layer from a carbon source (eg, a carbon-containing gas, eg, methane) and from hydrogen H ₂ , followed by nitrogen treatment of the just formed surface modification layer. The nitrogen treatment for forming a nitrogen-based polar group on the surface-modified layer may be performed by a plasma treatment with N ₂ gas. The deposition of the surface modification layer may be performed at atmospheric or reduced pressure by plasma excitation, such as DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. . The plasma polymerized surface modification layer may be deposited on a carrier, a thin sheet, or both. As mentioned earlier for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Using reaction conditions and feed gas control to control the film chemistry, density, and functionalities of the surface modified layer for the desired application, and to control film properties Thereby, the surface energy of the bonding surface can be adjusted. The nitrogen-based polar groups formed during the subsequent plasma treatment do not condense with the silanol groups to form a permanent covalent bond, and are therefore required to deposit a film or structure on a thin sheet. During the subsequent processing that takes place, the degree of bonding between the thin sheet and the carrier can be controlled.

In the examples in Table 9 below, various conditions were used to nitrogen treat a plasma polymerized film deposited on a glass carrier. The glass carrier was a substrate manufactured from "Corning""EagleXG" (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to deposition of the surface modification layer, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques. The surface modification layer was deposited in an Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK) in a dielectrically coupled plasma (ICP) configuration mode. Here, the carrier was placed on a platen, 50 W of 13.56 MHz energy was applied thereto, and a coil was placed on the platen, and 1500 W of 13.5 MHz RF energy was applied thereto. 20 sccm of methane (CH ₄ ) and 40 sccm of hydrogen (H ₂ ) were flowed into a tank at a pressure of 5 mTorr (about 0.67 Pa). For all samples listed in Table 9, the surface treatment time was 60 seconds and the platen temperature was 30 ° C. After the above-described deposition, the surface modified layer was treated with nitrogen. Specifically, during processing, a specific wattage (described in the “RF Bias” column) of 13.56 MHz RF energy is applied to the platen, a coil is placed over the platen, and a specific wattage ( 13.5 MHz RF energy (described in the “Coil” column) was applied. The N _2, was flowed into the vessel at a flow rate of 40sccm over a listed time in the table (s (s)). Thus, for example, the notation of nitrogen treatment in Table 9 for Example 9a reads as follows: In an Oxford ICP apparatus, 40 sccm of N ₂ is flowed into a tank at a pressure of 5 millitorr (about 0.67 Pa). 1500 W of 13.5 MHz RF energy was applied to the showerhead; 300 W of 13.56 MHz RF energy was applied to the platen on which the carrier was placed. The temperature was controlled at 30 ° C. and the treatment was performed for 10 seconds. The notation for the remaining examples can be read as well. The surface energy was measured for three different test liquids (in this case, deionized water (indicated in the “W” column), hexadecane (indicated in the “HD” column), and diiodomethane (in “DIM”). Calculated in mJ / m ² (millijoules per square meter) by using the contact angle (CA) and Wu model shown in the column). For the surface energies, the polarity (P) and dispersion (D) components and the total (T) are shown.

Examples 9a-9j may use various conditions for the nitrogen treatment of the surface modified layer formed by methane / hydrogen, so that various surface energies suitable for bonding to thin glass sheets, ie, , About 53 mJ / m ² (Example 9i) to about 63 mJ / m ² (Example 9b). These surface energies obtained after nitrogen treatment increased from about 42 mJ / m ² (obtained from the base layer formed from plasma polymerization of methane and hydrogen). It was observed that the thin glass and carrier bonded by the surface modified layer formed as in Examples 9a-9j did not adhere permanently after annealing at 450 ° C., ie, at 400 ° C. Pass the temperature test item (c). Outgassing tests were not performed on these samples. Also, these examples are strong enough to withstand FPD processing (including the vacuum test (1), wet process test (2), and ultrasonic test (5) described above) and have sufficient peel force. It remained peelable on application. Exfoliation allows for the removal of devices made on thin glass and the reuse of carriers.

  The thin glass sheets bonded to each of the carriers, as in the example in Table 9, were from "Corning" "Willow" Glass (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate-free alkali glass. The substrates were manufactured and had thicknesses of 100, 130, and 150 micrometers. Prior to bonding, the "Will" Glass was cleaned using an oxygen plasma followed by SC1 and / or SC2 chemistry and standard cleaning techniques.

  In the example of Table 9, the bonding surface on which the surface modification layer was disposed was glass, but need not be. Alternatively, the bonding surface may be another suitable material having similar surface energies and properties as glass, for example, silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

Introduction of polar groups into the carbonaceous surface modification layer by continuous treatment of N _{2 and} then H ₂ Use a plasma polymerized membrane to adjust the surface energy of the bonding surface and create alternative polar group bonding sites thereon Another example is the deposition of a thin film of the surface modification layer from a carbon source, eg, methane (carbon-containing gas), and from hydrogen H ₂ , followed by nitrogen and then hydrogen of the surface modification layer just formed. Is a continuous process. The deposition of the surface modification layer may be performed at atmospheric or reduced pressure and by plasma excitation, such as DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. Done. The plasma polymerized surface modification layer may be deposited on a carrier, a thin sheet, or both. As mentioned earlier for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Using reaction conditions and feed gas control to control the film chemistry, density, and functionalities of the surface modified layer for the desired application, and to control film properties Thereby, the surface energy of the bonding surface can be adjusted. The nitrogen-based polar groups formed during the subsequent plasma treatment do not condense with the silanol groups to form a permanent covalent bond, and therefore have to be deposited on a thin sheet to deposit a film or structure. During the subsequent processing that takes place, the degree of bonding between the thin sheet and the carrier can be controlled.

In the examples in Table 10 below, various conditions were used to treat (with nitrogen and then hydrogen) plasma-polymerized films deposited on glass supports. The glass carrier was a substrate manufactured from "Corning""EagleXG" (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to film deposition, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques. These films were deposited in an Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK) in a dielectrically coupled plasma (ICP) configuration mode. Here, the carrier was placed on a platen, 50 W of 13.56 MHz energy was applied thereto, and a coil was placed on the platen, and 1500 W of 13.5 MHz RF energy was applied thereto. 20 sccm of methane (CH ₄ ) and 40 sccm of hydrogen (H ₂ ) were flowed into a tank at a pressure of 5 mTorr (about 0.67 Pa). For all samples listed in Table 10, the surface treatment time was 60 seconds and the platen temperature was 30 ° C. After the deposition described above, the surface modified layer was continuously treated with nitrogen and then with hydrogen. Specifically, in each case, the nitrogen treatment, flushed with N ₂ for 40sccm to the bath, in the vessel, and applying RF energy 13.5MHz of 1500 W; pressure vessel is 5 mTorr (about 0.67 Pa) 50 W, 13.56 MHz RF energy was applied to the platen; the treatment was performed for 60 seconds. Then, during the hydrogen treatment, a specific wattage (described in the “RF” column of Table 10) of 13.56 MHz RF energy was applied to the platen, the coil was placed over the platen, and the specific wattage was added. A number (13.5 MHz) of RF energy at 13.5 MHz was applied. The H _2, was flowed into the vessel at a flow rate of 40sccm over a listed time in the table (s (s)). Thus, for example, the notation for hydrogen treatment (as described above, after thin film deposition and its N ₂ treatment, as described above) in Table 10 for Example 10a reads as follows: in the Oxford ICP apparatus, 40 sccm of H ₂ was pumped into the bath at a pressure of 20 mTorr (approximately 2.67 Pa); 750 W of 13.5 MHz RF energy was applied to the showerhead; 50 W of 13.56 MHz RF energy was applied to the carrier. A voltage was applied to the platen placed above and the treatment was performed for 15 seconds. The notation for the remaining examples can be read as well. The surface energy was measured for three different test liquids (in this case, deionized water (indicated in the “W” column), hexadecane (indicated in the “H” column), and diiodomethane (in “DIM”). Calculated in mJ / m ² (millijoules per square meter) by using the contact angle (CA) and Wu model shown in the column). For the surface energies, the polarity (P) and dispersion (D) components and the total (T) are shown.

Following a N ₂ of the formed methane and hydrogen plasma polymerization surface modification layer continuous plasma treatment of H _2, in order to achieve different surface energy can be carried out under various conditions. As can be seen from Table 10, the surface energies varied from about 60 mJ / m ² (Example 10d) to about 64 mJ / m ² (Examples 10a, 10n, 10o, and 10p). It is suitable for bonding to thin glass sheets. It was observed that the thin glass and carrier bound by the surface modified layer formed as in Examples 10a-10p did not adhere permanently after annealing at 450 ° C., ie, they did not reach 400 ° C. The temperature test item (c) was able to pass. Also, these examples are strong enough to withstand FPD processing (including the vacuum test (1), wet process test (2), and ultrasonic test (5) described above) and have sufficient peel force. It remained peelable on application. Exfoliation allows for the removal of devices made on thin glass and the reuse of carriers.

  The thin glass sheets bonded to each of the carriers as in the example of Table 10 were from "Corning" "Willow" Glass (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate-free alkali glass. The substrates were manufactured and had thicknesses of 100, 130, and 150 micrometers. Prior to bonding, the "Will" Glass was cleaned using an oxygen plasma followed by SC1 and / or SC2 chemistry and standard cleaning techniques.

  In the example of Table 10, the bonding surface on which the surface modification layer was disposed was glass, but need not be. Alternatively, the bonding surface may be another suitable material having similar surface energies and properties as glass, for example, silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

As a modification of the example in Table 10, a continuous treatment of nitrogen followed by hydrogen was also performed on the surface modified layer formed from methane. In this case, methane was used alone (without hydrogen) when the first surface modified layer was formed on the glass carrier by plasma polymerization. Specifically, 40 sccm of methane was flowed at a pressure of 5 millitorr (about 0.67 Pa) under a power of 1500/50 W for 60 seconds. Its surface energy was measured to be about 42 mJ / m ² . Nitrogen (15 mTorr pressure for 15 seconds, 40 sccm N ₂ at 1500/50 W power) followed by hydrogen (5 mTorr for 15 seconds). During continuous treatment with H ₂ ) of 40 sccm at a pressure of 1500/50 W and a power of about 64 mJ, the surface energy achieved on the bonding surface of the support is suitable for bonding thin glass sheets to glass supports. / M ² .

Continuous N ₂ and H ₂ treatment of the carbonaceous surface modification layer, as described above, achieves a surface energy of about 64 mJ / m ² , slightly slower than the bond front velocity typical for fluorinated surface modification layers At speed, an initial room temperature bond is formed in a thin glass sheet. With respect to the example in Table 10, it was observed that these samples did not adhere permanently after annealing at 450 ° C., ie, they could pass item (c) of the 400 ° C. temperature test. did it. Also, these examples are strong enough to withstand FPD processing (including the vacuum test (1), wet process test (2), and ultrasonic test (5) described above) and have sufficient peel force. It remained peelable on application. Exfoliation allows for the removal of devices made on thin glass and the reuse of carriers.

Introducing polar groups into the carbonaceous surface modification layer by continuous treatment of N ₂ -O _{2 and} then N ₂ based on the idea of trying to create more polar imide groups on the surface to increase the bond front rate, we studied the continuous plasma treatment of N ₂ -O ₂ then N ₂ carbonaceous surface modification layer.

This example of using a plasma polymerized membrane to adjust the surface energy of the binding surface and create an alternative polar group binding site thereon is illustrated by a carbon source, such as a carbon-containing gas (eg, methane), and hydrogen H _2. Deposition of a thin film of carbonaceous surface modification layer from Step _2, followed by continuous treatment of N ₂ —O _{2 and} then N ₂ of the surface modification layer just formed. The deposition of the surface modification layer may be performed at atmospheric or reduced pressure by plasma excitation, such as DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. . The plasma polymerized surface modification layer may be deposited on a carrier, a thin sheet, or both. As mentioned earlier for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Using reaction conditions and feed gas control to control the film chemistry, density, and functionalities of the surface modified layer for the desired application, and to control film properties Thereby, the surface energy of the bonding surface can be adjusted. The nitrogen-based polar groups formed during the subsequent plasma treatment do not condense with the silanol groups to form a permanent covalent bond, and therefore have to be deposited on a thin sheet to deposit a film or structure. During the subsequent processing that takes place, the degree of bonding between the thin sheet and the carrier can be controlled.

  In the examples in Table 11 below, various conditions were used to treat the plasma polymerized film deposited on the glass carrier to increase surface energy and include polar groups. The glass carrier was a substrate manufactured from “Corning” “Eagle XG” (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to deposition of the surface modification layer, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques.

In step 1, the surface modification layer was deposited in an Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK) in a dielectrically coupled plasma (ICP) configuration mode. Here, the carrier was placed on a platen, 50 W of 13.56 MHz energy was applied thereto, and a coil was placed on the platen, and 1500 W of 13.5 MHz RF energy was applied thereto. 20 sccm of methane (CH ₄ ) and 40 sccm of hydrogen (H ₂ ) were flowed into a tank at a pressure of 5 mTorr (about 0.67 Pa). For all samples listed in Table 11, the surface treatment time was 60 seconds and the platen temperature was 30 ° C.

After the above-described deposition in Step 1, in Step 2, the surface modified layer was treated with nitrogen and oxygen. Specifically, during the process of Step 2, 50 W 13.56 MHz RF energy was applied to the platen, the coil was placed on the platen, and 800 W 13.5 MHz RF energy was applied thereto. . The N ₂ and O _2, was flowed in the bath at the listed time in the table (s (s)) specific flow rate over (sccm). Thus, for example, the notation for step 2 in Table 11 for Example 11a reads as follows: After deposition of the surface modified layer in step 1, 35 sccm of N ₂ is replaced with 5 sccm of O _{2 in} an Oxford ICP apparatus. At the same time, a pressure of 15 mTorr (about 2.0 Pa) was poured into the bath; 800 W of 13.5 MHz RF energy was applied to the showerhead; 50 W of 13.56 MHz RF energy was placed on the carrier. Applied to the platen, the carrier was temperature controlled at 30 ° C. and the treatment was performed for 5 seconds. The notation for the remaining examples can be read as well.

After the above-described treatment in Step 2, in Step 3, the surface-modified layer was treated with nitrogen. Specifically, during the process of Step 3, 50 W 13.56 MHz RF energy was applied to the platen, the coil was placed on the platen, and 1500 W 13.5 MHz RF energy was applied thereto. . The N _2, was flowed in the bath at the listed time in the table (s (s)) specific flow rate over (sccm). Thus, for example, the notation for step 3 in Table 11 for Example 11a reads as follows: after the deposition of the surface modifying layer in step 1 and after the nitrogen-oxygen treatment in step 2, the Oxford ICP apparatus At 40 sccm N ₂ was flowed into the bath at a pressure of 5 mTorr (approximately 0.67 Pa); 1500 W of 13.5 MHz RF energy was applied to the showerhead; 50 W of 13.56 MHz RF energy was The carrier was applied to an overlying platen, the carrier was temperature controlled at 30 ° C., and the treatment was performed for 15 seconds. The notation for the remaining examples can be read as well.

Surface energy is calculated in mJ / m ² (millijoules per square meter) by using the contact angle (CA) and Wu model of three different test liquids (in this case, deionized water, hexadecane, and diiodomethane). did. For surface energies, the sum (T, including both polar and dispersive components) is shown. The binding energy was calculated in mJ / m ² as described above. The number of bubbles after the first bond is shown in the column titled "23C Area%", while the number of bubbles after the 400C temperature test is shown in the column titled "400C Area%". The number of bubbles was determined by an optical scanner as described below for "outgassing". Finally, the change in bubble area from the first at 23 ° C. to after the 400 ° C. temperature test is shown in the column titled “Differential Area%”.

Examples 11a-11e may use various conditions for the continuous treatment of nitrogen-oxygen and then nitrogen in the surface modified layer formed by methane / hydrogen, thereby making it suitable for bonding to thin glass sheets. That various surface energies suitable for bonding to thin glass sheets may be obtained, ie from about 65 mJ / m ² (Examples 11a and 11e) to about 70 mJ / m ² (Examples 11b and 11d). Is shown. Nitrogen - oxygen, these surface energy obtained after continuous processing of nitrogen was then increased from about 40~50mJ / m ² (obtained from methane and base layer formed from plasma polymerization of hydrogen). It was observed that the thin glass and carrier bound by the surface modified layer formed as in Examples 11a-11f did not adhere permanently after annealing at 400 ° C., ie, they did not adhere at 400 ° C. Pass the temperature test item (c). As shown in Examples 11a-11e, the change in bubble area% during annealing at 400 ° C. is consistent with no outgassing. On the other hand, the change in bubble area% during annealing at 400 ° C. for Example 11f is consistent with some outgassing of the material in the surface modified layer. Therefore, the step 3 is important for the surface modified layer deposited according to the conditions in Table 11 to have no outgassing. However, under other deposition / processing conditions for Steps 1 and 2, Step 3 would not need to obtain results without outgassing similar to those obtained by Step 3 for Examples 11a-e. Also, these examples are strong enough to withstand FPD processing (including the vacuum test (1), wet process test (2), and ultrasonic test (5) described above), and after a 400 ° C. temperature test. , And remained peelable by application of a sufficient peeling force. Exfoliation allows for the removal of devices made on thin glass and the reuse of carriers.

The effects of these successive steps on surface energy, binding energy, and bubble generation are shown in Table 11. Increasing the oxygen fraction in the N ₂ -O ₂ step, the surface energy is reduced, the bubbles generated in the gas discharge test was increased. The performance for a short (about 5 seconds) low oxygen fraction (38/2) N ₂ —O ₂ step followed by a short (15 seconds) N ₂ plasma treatment (Example 11d) results in 69 mJ / during a 400 ° C. temperature test. A surface energy of m ² and a bubble area of 1.2% result (the change in bubble area% from 23 ° C. is −0.01, indicating no outgassing). The performance of Examples 11a-e is comparable to a fluorinated surface modified layer in applications up to a 400 ° C temperature test.

  The thin glass sheets bonded to each of the carriers as in the example of Table 11 were from "Corning" "Willow" Glass (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free glass. The substrates were manufactured and had thicknesses of 100, 130, and 150 micrometers. Prior to bonding, the "Will" Glass was cleaned using an oxygen plasma followed by SC1 and / or SC2 chemistry and standard cleaning techniques.

  In the example of Table 11, the bonding surface on which the surface modification layer was disposed was glass, but need not be. Alternatively, the bonding surface may be another suitable material having similar surface energies and properties as glass, for example, silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

  The above example illustrates how an inductively coupled plasma (ICP) system can be used to deposit a thin organic surface modification layer suitable for controllably bonding a thin glass sheet to a glass carrier for device processing. It illustrates how it can be done. However, the scalability of this solution for display applications (large area substrates are advantageous) is a concern. ICP instruments utilize planar, cylindrical, or hemispherical coils to inductively couple current to create a time-dependent magnetic field that circulates ions. Typically, a second RF source is connected to a platen on which the substrate rests. An advantage of an ICP plasma is that the ICP source can achieve a high level of ionization independent of the substrate bias controlled by the platen RF source. Current parallel plate reactive ion etching (RIE) systems cannot achieve high levels of ionization. Moreover, bias and ionization are coupled by RF power and pressure. Although TEL and the like have extended the ICP etching apparatus to the fifth generation, it is difficult to extend the ICP etching apparatus to a greater extent in order to produce a uniform ICP plasma source. On the other hand, the RIE mode process is suitable for parallel plate equipment extended to the tenth generation. Therefore, the inventors of the present application have studied ways to achieve results similar to those achieved by ICP equipment as described above in the RIE mode process.

  Simply using an Oxford apparatus (equivalent to that used for the deposition of the fluorinated surface modification layer) in RIE mode (no coil output) and 200 W bias output, the RIE mode surface modification from the non-fluorinated feedstock. Initial attempts to produce a porous layer resulted in a dark, thick layer that could be nitrogen modified and bonded to a thin glass sheet. However, after the 400 ° C. treatment test, the darkened material produced many bubbles covering about 25% of the bonded area. Characterization of this dark deposit by spectroscopic ellipsometry indicates that the thickness of the film is about 100 nm, with a much narrower optical band gap compared to 1.7 eV for the ICP deposited surface modified layer. 0.6 eV was shown. From this result, it was concluded that the material appeared to be graphite and that increasing the hydrogen content would be a consideration for reducing bubble formation.

RIE process variables, H ₂ / CH ₄ ratio, RF power, and to map the pressure, an experiment was conducted to acquire emission spectroscopy (OES) spectrum. However, these ratios could not be matched within the process window of the Oxford equipment used. However, this experiment showed that the process would benefit from very high hydrogen dilution of the polymer forming gas, high RF power, and low pressure.

In addition to the OES leading to the process conversion from ICP mode to RIE mode, the residual gas to map gaseous species present in the Oxford instrument as a function of hydrogen / methane ratio, RF power, and pressure in RIE mode. Analysis (RGA) was used. A contour plot of m / e = / 16 vs. pressure and H ₂ / CH ₄ gas ratio again showed that high hydrogen dilution was beneficial in meeting an ICP ratio of about 44. Higher alkanes correlate with decreasing H ₂ / CH ₄ gas ratio and increasing pressure. The contour plot shows m / e = 28/16 to increase with both RF and H ₂ / CH ₄ gas ratio. Fitting RGA response surface, H ₂ / CH ₄ ratio and C ₂ H ₆ / CH ₄ ratio is 40: 1 H ₂ / CH _4, 25 millitorr (about 3.3 Pa), are matched with the RF 275W Suggests that The carbonaceous RIE mode surface modified layer deposited under these conditions was consistent with an ICP mode carbonaceous surface modified layer thickness of about 6 nm and an optical band gap of 1.6 eV. Initial experiments with nitrogen plasma treatment of the carbonaceous RIE surface modification layer also showed low bubbling.

  The kinetics of the deposition of the RIE mode carbonaceous surface modification layer using the process specified by this RGA experiment is shown in FIGS. The surface energies, including total (T) and polar (P) and dispersive (D) components, are shown in FIG. It has a slight peak at a deposition time of 60 seconds and the surface energy is relatively unchanged, while in FIG. 15, it can be seen that the film thickness increases almost linearly on a logarithmic / logarithmic scale. This is not a self-limiting process because etchback from hydrogen cannot keep up with polymer deposition.

As described above, from experience, about 50 mJ / m ² or more or about 65 mJ / m ² or more surface energy, the binding of the first room, and both during thermal cycling, beneficial to bubble area to minimize It turned out to be. From FIG. 14, it can be seen that the surface energy is just on the boundary. In some cases, depending on the time-temperature cycle experienced, as well as other FPD processes that must withstand, it may be suitable to bond the thin sheet to the carrier. However, on the other hand, it would be beneficial to increase the surface energy of this surface modified layer. Any of the subsequent treatments described above, for example, ammonia treatment, nitrogen treatment, continuous treatment of nitrogen and then hydrogen, nitrogen-oxygen treatment, and continuous treatment of nitrogen-oxygen and then nitrogen can be used. As an example, a nitrogen-oxygen treatment is described with respect to Table 12.

Introduction of polar groups into the carbonaceous surface modified layer by N ₂ -O ₂ treatment Another method using a plasma polymerized membrane to adjust the surface energy of the bonding surface and create alternative polar group bonding sites thereon An example is the deposition of a thin film of a surface modification layer in RIE mode from a carbon source (eg, methane, a carbon-containing gas) and from hydrogen (H ₂ ), followed by the deposition of the surface modification layer just formed. Nitrogen-oxygen treatment. The nitrogen-oxygen treatment may be performed by, for example, a nitrogen-oxygen plasma treatment. The deposition of the surface modification layer may be performed under atmospheric pressure or reduced pressure. The plasma polymerized surface modification layer may be deposited on a carrier, a thin sheet, or both. As mentioned earlier for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Control of reaction conditions and feed gas can be used to control the chemistry for tailoring film thickness, density, and functional groups to the desired application, and by controlling the properties of the film, the bonding surface Surface energy can be adjusted. The nitrogen-based polar groups formed during the subsequent nitrogen-oxygen treatment do not condense with the silanol groups to form permanent covalent bonds, thus depositing a film or structure on a thin sheet. During the subsequent processing that takes place, the degree of bonding between the thin sheet and the carrier can be controlled.

In the examples in Table 12 below, various conditions were used to deposit a plasma-polymerized surface modified layer film on a glass carrier. The glass carrier was a substrate manufactured from "Corning""EagleXG" (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to film deposition, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques. The surface modification layer was deposited in an Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK) in RIE configuration mode. Here, the carrier was placed on a platen, to which 275 W of RF energy was applied, a coil was placed on the platen, and no energy was applied to it. In step 1, 2 sccm of methane (CH ₄ ) and 38 sccm of hydrogen (H ₂ ) were flowed into a tank at a pressure of 25 mTorr (about 3.3 Pa). For all samples listed in Table 12, the surface treatment time was 60 seconds and the platen temperature was 30 ° C. After the above-described deposition, in step 2, the surface modified layer was treated with nitrogen and oxygen. Specifically, during the process of Step 2, a specific wattage (listed in the “RF” column) of 13.56 MHz RF energy is applied to the platen, a coil is placed over the platen, and the energy is Was not applied. This over "time (s)" in Table columns listed Time (sec (s)), the N _2, "N2" flowed into the vessel at a flow rate of the listed sccm the columns of the O ₂ , "O2" at the flow rate of sccm listed in the column. The bath was at a pressure in millitorr, as listed in the "Pr" column. Thus, for example, the notation for step 2 nitrogen and oxygen treatment in Table 12 for Example 12b reads as follows: In an Oxford ICP apparatus, 25 sccm of N ₂ with 25 sccm O _{2 at} a pressure of 10 mTorr. (Approximately 1.3 Pa) into the bath; 300 W of 13.56 MHz RF energy was applied to the platen on which the carrier was placed, the carrier was temperature controlled to 30 ° C., and the treatment took 10 seconds. I went over. The notation for the remaining examples can be read as well.

The surface energy was determined by using the contact angles of three different test liquids (in this case, deionized water (W), hexadecane (HD), and diiodomethane (DIM)) and the Wu model, in mJ / m ² (per square meter). In millijoules). For the surface energies, the polarity (P) and dispersion (D) components and the total (T) are shown. The thickness of the surface modification layer (expressed in Å "th"), the deposition of the surface modification layer and N ₂ -O ₂ average surface roughness of the support after the treatment (expressed in Å "Ra") , Binding energy (“BE” expressed in mJ / m ² ) and cell area% change (cell area after first bonding a thin glass sheet to a support via a surface modification layer at room temperature, 400 ° C. process The test also shows the “Δ bubble%” between the bubble area after heating the carrier).

  The thin glass sheets bonded to each of the carriers as in the example of Table 12 were from "Corning" "Willow" Glass (obtained from Corning Incorporated, Corning, NY), which is an alkali aluminoborosilicate glass. The substrates were manufactured and had thicknesses of 100, 130, and 150 micrometers. Prior to bonding, the "Will" Glass was cleaned using an oxygen plasma followed by SC1 and / or SC2 chemistry and standard cleaning techniques.

  In the example of Table 12, the bonding surface on which the surface modification layer was disposed was glass, but need not be. Alternatively, the bonding surface may be another suitable material having similar surface energies and properties as glass, for example, silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

  From the treatments in the examples in Table 12, after treatment at 400 ° C .: all of Examples 12a to 12j show a change in bubble area percent of less than 2, which is consistent with no outgassing at this temperature (Table (See 12 ΔBubble% column), and each of samples 12a, 12b, 12c, 12g, and 12j had a binding energy capable of peeling a thin sheet from the carrier after this temperature test (Table 12 BE column), but Examples 12d, 12e, 12f, 12h, and 12i failed to peel after the 400 ° C. process test, as indicated by the 2500 value in the BE column of Table 12. I understand.

Surface energy, bubble area, binding energy, and ellipsometric thickness are mapped as a function of% O2, RF, and pressure, as in the example in Table 12. It can be seen that the reduction in thickness correlates with increasing RF power (compare Example 12g with Example 12b) and% O2 (compare Example 12a with Example 12b), which is consistent with the ashing of the hydrocarbon layer. . Binding energy was dependent only on pressure: samples treated at 10 mTorr (approximately 1.3 Pa) could be peeled off after annealing at 400 ° C. (see Examples 12a, 12b, 12c, 12g). Those processed at 35 millitorr (approximately 4.7 Pa) or higher could not be obtained. See also, for example, Example 12d with a binding energy of 2500, treated at 40 mTorr (about 5.3 Pa), and Example 12e with a pressure of 70 mTorr (about 9.3 Pa) and a binding energy of 2500. A binding energy of 2500 in the "BE" column indicates that the thin glass sheet could not be peeled from the carrier. All surface energies of the treated films were 65-72 mJ / m ² irrespective of thickness. See Examples 12a to 12i and 12k. These results suggest that the discontinuous film is caused by the high pressure of the N ₂ -O ₂ plasma treatment. In fact, high pressure removes the membrane abruptly, whereby low pressure is beneficial. For bubble generation, the amount appeared to decrease as% O2 * RF increased. In addition, the partial pressure of H ₂ O decreases with increasing% O 2 and increasing RF; the thickness of the surface modification layer decreases with increasing pressure in step 2, and the Δbubble% increases. Increases with pressure (thus, lower pressures are beneficial during step 2); as the treatment time increases, the thickness of the surface modifying layer decreases, as well as the polar groups decrease, and thus Short processing times have been found to be beneficial.

Appropriate binding energy and bubble generation balance were determined. Nitrogen - starting point of the oxygen treatment was 50% O _2, 10 mTorr (about 1.3 Pa), 300 W and various processing times. Three sets of samples, 20 seconds, and 60 seconds and 180 seconds RIE CH ₄ -H ₂ deposition, followed by 0 seconds, 5 seconds, was prepared by 15 seconds, and 60 seconds of N ₂ -O ₂ plasma treatment . Both the surface energy and the binding energy, regardless of the CH ₄ -H ₂ deposition time, the peak in the N ₂ -O ₂ plasma treatment time of 5-15 seconds. Thin 20 seconds CH ₄ -H ₂ layers are removed, thin glass sheets are permanently bonded to the carrier. Before the polymer layer is removed, a peak occurs, which is consistent with the formation of polar groups on the polymer film, rather than simply ablation exposing the glass substrate. Bubble area increases with deposition time of the surface modified layer increases, thus, simply increasing the thickness of the surface-modified layer in order to avoid subsequent too ablation in N ₂ -O ₂ surface treatment, Not useful. Thus, the good compromise between the coupling and the bubble area, is the balance of the deposition time of the surface modification layer and the N ₂ -O ₂ processing time. (Since it will lead to greater thickness than the leads to an increase in outgassing, not too long) deposition time of the surface modification layer and, N ₂ -O ₂ processing time (- removing surface modification layer or removed ( Not too long to provide permanent bonding of the carrier to the thin sheet) but long enough to include polar groups in the surface modification layer). Good compromise has a 60-second RIE deposition of carbonaceous layer, 5 to 10 seconds shorter N ₂ -O ₂ processing time subsequent. For RIE mode, Examples 12a, 12b, 12c, 12g, and 12k work well.

Use the built-XPS N1s speciation polar groups to the surface modification layer, N ₂ -O ₂ plasma treatment was studied a mechanism for forming a high-polar surface. Studied speciation of these surface modification layer, in order to confirm, glass deposited completely cover as "Eagle XG" on the glass wafer, followed by, in N ₂ / O ₂ plasma over various periods The surface chemistry of the treated, relatively thick CH ₄ / H ₂ films was studied. An advantage of thick hydrocarbon films is that they can identify nitrogen species that occur only on hydrocarbon films and distinguish them from those that occur on exposed glass.

By exposing the surface composition of the "Eagle XG" glass wafer is CH ₄ / H ₂ plasma for the first 600 seconds, to deposit a thick hydrocarbon layer, followed by, N ₂ over the 5,15,60 and 600 seconds / O ₂ is exposed to the plasma. Elements present in the glass (such as Al and Ca) were not detected for the 5 and 15 second treatments, indicating that in those cases the carbonaceous membrane layer was thicker than the XPS probe depth, which was about 10 nm. ing.

Exposure of the carbonaceous film to the N ₂ / O ₂ plasma for 60 seconds and 600 seconds results in some thinning of the carbonaceous layer, in which case XPS can detect elements that occur in the glass. This observation is further confirmed by examining the surface concentration of carbon. For the 60 and 600 second treatments, the C concentration was less than 10 at%, strongly suggesting that the surface was partially covered by the carbonaceous layer.

NH ₃ ⁺ species are detected only when a significant amount of the carbonaceous film has been removed by etching. This strongly suggests that the NH ₃ ⁺ species appear to be present only on the glass, and that other species mainly involve the reaction between nitrogen and the carbonaceous layer. The speciation of the nitrogen species as a percentage of all elements on the surface (ie, the fraction of the species x the fraction of nitrogen detected) is shown in Table 13 below.

It can be seen that the main function of this N ₂ —O ₂ treatment is the etching of the carbonaceous surface modified layer. In fact, for the 60 and 600 second treatments, there is very little carbonaceous material on the surface. Other observations, a very short N ₂ -O ₂ processing time, for example, even after 5 and 15 seconds, is that the nitrogen species present in the surface modification layer. Thereafter, the nitrogen species sharply decreases, while the ammonia species (indicating the presence of the underlying glass surface) sharply increases. By XPS evaluation of carbon speciation about N ₂ -O ₂ plasma treatment for 5 seconds carbonaceous surface modification layer, several different species containing oxygen and nitrogen becomes also clear that on the surface modification layer Was. The presence of oxygen containing species led to the idea that O ₂ plasma alone would be sufficient to provide polar groups to the surface modified layer. In fact, this has been found to be the case and is discussed below.

Estimating surface coverage by calculating the ratio of NH ₃ ⁺ / Σ (total nitrogen compounds), based on the assumption that NH ₃ ⁺ species occur only on glass and not on carbonaceous layers Can be. The result of the estimation of the surface coverage is given in FIG. There is little change between 5 seconds and 15 seconds. The biggest change appears between 15 and 60 seconds of N ₂ -O ₂ plasma treatment time.

The model of the N ₂ —O ₂ plasma treatment of the carbonaceous surface modified layer is as follows. The CH ₄ -H ₂ deposition, the hydrocarbon layer is caused to continuous. In the first few seconds of the N ₂ -O ₂ plasma treatment, the polar -NH ₂ groups are formed on the polymer surface as the hydrocarbon layer is oxidized and ablated. An imide or amide group may also be formed at this time, but its XPS is undefined. When N ₂ -O ₂ plasma treatment is long, polymer removal reaches the glass surface where the interaction with the N ₂ -O ₂ plasma and glass surfaces, polar -NH ₃ ⁺ group is formed.

O ₂ alone as a surface treatment for the surface modified layer
As an alternative to N ₂ -O ₂ processing carbonaceous layer increases the surface energy, in order to form a polar group on the carbonaceous layer, the use of O ₂ alone was also studied. As described above, by XPS carbon speciation of N ₂ -O ₂ plasma treatment for 5 seconds carbonaceous layer, oxygen-containing species was in fact, shown to be present on the surface modification layer. Therefore, attempts to O ₂ treatment of the carbonaceous layer. The O ₂ treatment was performed in both the ICP mode and the RIE mode.

In the ICP mode, a basic carbonaceous layer was formed as in Step 1 of Table 11 above. The surface treatment of step 2 is then performed by flowing 40 sccm of O ₂ and 0 sccm of N ₂ at a power of 800/50 W under a pressure of 15 mTorr (about 2.0 Pa), whereby the surface energy is reduced to a desired value. And the desired polar group was generated on the surface of the carbonaceous layer. The thin glass sheet readily bonded to the surface modified layer at room temperature. It was also observed that the sample did not bond permanently after annealing at 450 ° C., ie, the sample was able to pass item (c) of the 400 ° C. processing test. This sample is strong enough to withstand FPD processing (including the vacuum test (1), wet process test (2), and ultrasonic test (5) described above), and peels off when a sufficient peeling force is applied. It remained possible. Exfoliation allows for the removal of devices made on thin glass and the reuse of carriers.

In the RIE mode, a basic carbonaceous layer was formed as in Step 1 of Table 12 above. Then, the surface treatment of Step 2 was performed by flowing 50 sccm O ₂ and 0 sccm N ₂ at a power of 200 W under a pressure of 50 mTorr (about 6.7 Pa). As in the ICP mode, these conditions resulted in the desired increase in surface energy and the creation of the desired polar groups on the surface of the carbonaceous layer. The thin glass sheet readily bonded to the surface modified layer at room temperature. It was also observed that the sample did not bond permanently after annealing at 450 ° C., ie, the sample was able to pass item (c) of the 400 ° C. processing test. Also, this sample is strong enough to withstand the FPD processing (including the vacuum test (1), the wet process test (2), and the ultrasonic test (5) described above), and the application of a sufficient peel force. And remained peelable. Exfoliation allows for the removal of devices made on thin glass and the reuse of carriers.

Thus, O ₂ treatment, was found to behave similarly to N ₂ -O ₂ process. Similar considerations apply with respect to the balance of the initial surface modification layer deposition time (thickening) and O ₂ treatment.

XPS analysis of the carbonaceous layer with the hydrocarbon polymer deposited in a small amount of fluorine ICP mode showed some atomic% F, about 2.2% F. This results in the fact that Oxford is used for fluorine and chlorine etching of glass, dielectrics, and metals. A small amount of fluorine has been found to be beneficial to the properties of the hydrocarbon-deposited surface modification layer. Cleaning process of a typical reactor, and SF ₆ -O ₂ wash, followed by a O ₂ cleaning preliminary H ₂ plasma cleaning. Each step is 30 minutes long and includes a pump / purge step between steps. Since the etch rate of the hydrocarbon polymer is significantly faster than O ₂ alone, SF ₆ —O ₂ is used for the first wash. H ₂ plasma cleaning step will remove most contaminating amounts of fluorine from the sediment on the walls of the reactor. If omitted of H ₂ plasma cleaning, it would be expected that more containing a large amount of fluorine in the surface modification layer of hydrocarbons. FIG. 16 shows the effect of omitting the H ₂ plasma cleaning on the hydrocarbon surface modified layer. The binding energy is reduced, there is no significant increase in bubble generation, and there is no permanent binding up to 600 ° C. Thus, a small amount of fluorine in the hydrocarbon surface modification layer, ie, at least up to about 3% fluorine, is beneficial.

Surface roughness The change of surface roughness of the bonding surface of glass due to the deposition of surface modification layer formed by hydrocarbon was studied. Specifically, a surface modified layer formed from methane-hydrogen which was subsequently treated with nitrogen and then with hydrogen was selected. Methane - to form a surface modified layer of hydrogen, followed by the N ₂ consecutive situ, and then over in H ₂ plasma treatment (60 seconds, 20CH ₄ 40H ₂ 5 millitorr (about 0.67 Pa), 1500 / 50 W, then, over 15 seconds, 40N ₂ 5 millitorr (about 0.67 Pa), 1500/50 W, then, over 15 seconds, 40H ₂ 15 mTorr (about 2.0 Pa), by performing 1500/50 W) Two carriers were prepared. The surface modifying layer of a first carrier (eg 14a), and O ₂ plasma cleaning was removed by SC1 cleaning subsequent. The surface modified layer of the second carrier (Example 14b) was left in place. A third support (Example 14c) was used as a reference and had no surface modification layer applied thereto. Using the AFM, the surface roughness of the removed carrier (Example 14a), the carrier still having the surface modified layer thereon (Example 14b), and the reference carrier (Example 14c) were determined. evaluated. The Rq, Ra, and Rz ranges from AFM measurements are shown in Table 14 in nm (nanometers). The roughness of Examples 14a and 14b is indistinguishable from that of Example 14c. It should be noted that for Example 14c, the excess z-range in the 5x5 micrometer scan was due to particles in the scanned area. Thus, it can be seen that the surface modified layer formed by the hydrocarbon of the present disclosure does not change the surface roughness of the bonding surface of the glass. In certain circumstances, the constant surface roughness of the binding surface may be beneficial, for example, for carrier recycling. The glass carrier in these examples was a substrate made of "Corning""EagleXG" (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass.

General Considerations The above-described separation of the thin sheet from the carrier in Examples 2-12, at room temperature, without any additional heat or chemical energy, to alter the bonding interface between the thin sheet and the carrier Done. The only energy input is the mechanical traction and / or peel force.

Since the surface modification layers of Examples 3 and 5-12 are thin organic layers, they are sensitive to oxygen in thermal and plasma treatments. Therefore, these surface modification layers should be protected during device manufacture. The surface modification layer may be protected during thermal processing by use of a non-oxygen containing environment (eg, a N ₂ environment). Alternatively, depositing a protective coating, e.g., a thin metal layer, over the edge of the interface between the bonded thin glass sheet and the carrier may protect the surface modified layer from the effects of an oxygen environment at elevated temperatures. Is enough.

  If both the thin sheet and the carrier have a glass binding surface, the surface-modifying layer described above in Examples 3 to 12 can be applied to both the carrier, the thin sheet, or both the carrier and the thin sheet surface bonded together. Can be applied. Alternatively, if one binding surface is a polymeric binding surface and the other is a glass binding surface (as described further below), the appropriate binding surface described above in Examples 3-12 A surface modification layer (based on the surface energy of the polymer binding surface) is applied to the glass binding surface. Furthermore, the entire carrier or thin sheet need not be made of the same material, but as long as its binding surface is suitable for receiving the surface modifying layer of interest, and different layers and / or Material may be included. For example, the bonding surface may be glass, glass ceramic, ceramic, silicon, or metal, and the remainder of the carrier and / or thin sheet may be of a different material. For example, the bonding surface of thin sheet 20 may be of any suitable material including, for example, silicon, polysilicon, single crystal silicon, sapphire, quartz, glass, ceramic, or glass ceramic. For example, the bonding surface of carrier 10 is a glass substrate or another suitable material having a surface energy similar to glass, such as silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz. Good.

As can be seen from the examples described here, the surface modification layer, together with its subsequent processing, provides a method for widely varying the surface energy on the bonding surface of the glass. For example, all of the previous examples show that the surface energy of the bonding surface of the glass can be varied from about 36 mJ / m ² (as in Example 5g) to about 80 mJ / m ² (Example 5f). Using a non-fluorinated surface material in a one-step process without subsequent surface treatment, the surface energy of the bonding surface of the glass can be from about 37 mJ / m ² (Example 16b) to about 67 mJ / m ² (Example It can be seen that it can be changed from 7h to 7j). Using a carbonaceous surface modification layer with subsequent treatment to increase polar groups, the surface energy of the glass binding surface can range from about 52 mJ / m ² (Example 12j) to about 74 mJ / m ² (Example 8a). You can see that it can be changed. Whether using a non-fluorinated feed in a one-step process or a two-step process, the surface energy of the bonding surface of the glass is from about 37 mJ / m ² (Example 16b) to about 74 mJ / m ² (Example 8a). You can see that it can be changed up to With the subsequent treatment, whether using a fluorine-containing or non-fluorine-containing feedstock to deposit the surface-modifying layer, the surface energy of the bonding surface of the glass is about 41 mJ / m ² (eg, 5 mJ / m ² ). ) To about 80 mJ / m ² (Example 5f).

  Moreover, as can be seen from the examples described here, the thickness of the surface modified layer can vary widely. Desirable results have been obtained with a surface modification layer thickness ranging from about 2 nm (as in Example 3) to about 8.8 nm (as in Example 12c).

Using controlled joins
One use of controlled bonding with reusable carrier surface modification layers (including heat treatment of materials and associated bonding surfaces) is in processes requiring temperatures above 600 ° C., for example, in LTPS processing Is to provide for the reuse of the carrier in the article experiencing the Using surface modification layers (including heat treatment of materials and bonding surfaces), as exemplified by the previous examples 2e, 3a, 3b, 4c, 4d, and 4e, and the examples in Table 5, Recycling of the carrier under temperature conditions may be provided. In particular, these surface-modifying layers are used to change the surface energy of the area of overlap between the bonding area of the thin sheet (having a glass binding surface) and the carrier (having a glass binding surface), After processing, the entire thin sheet may be separated from the carrier. The thin sheet can be separated all at once, or partially separated, for example, when a device manufactured on a section of the thin sheet is first removed, and then the remaining sections can be removed and reused. The carrier may be washed for use. If the entire thin sheet is removed from the carrier, the carrier can be reused, such as by simply placing another thin sheet thereon. Alternatively, the carrier may be once again prepared to carry a thin sheet by washing and forming the surface modification layer again. The surface modification layer prevents permanent bonding of the thin sheet to the carrier and can be used in processes where the temperature is above 600 ° C. Of course, these surface modified layers will control the energy of the bonding surface during processing at temperatures above 600 ° C., but will produce a thin sheet and carrier combination that will survive processing at lower temperatures. And may be used in such lower temperature applications to control binding. Further, if the thermal processing of the article does not exceed 400 ° C., Examples 2c, 2d, 4b, and the examples in Tables 7-11 (including those discussed as alternatives to the examples in Table 10), Examples 12a, 12b, 12c, 12 g, 12 g, and O ₂ surface-modified layer which is illustrated by way of example in surface treatment with only may also be used as well.

Surface-modified layer described herein, for example, the example of Table 3, Example 4b, 4c, 4d, 4e, examples of Tables 5 and 7 to 11, examples 12a, 12b, 12c, 12g, 12j, and O ₂ only One of the advantages of using a surface modified layer, including the example of surface treatment with, is that the carrier can be reused at the same size. That is, the thin sheet is removed from the carrier, the surface modifying layer is removed from the article in a non-destructive manner (eg, O ₂ or other plasma cleaning), and the carrier is cut in any manner (eg, at its edges). The carrier may be reused without having to do so.

Providing a controlled bonding area The second use of controlled bonding by a surface modifying layer (including heat treatment of the material and associated bonding surface) is controlled between the glass carrier and a thin sheet of glass. To provide a combined area. More specifically, the use of a surface-modifying layer allows the formation of areas of controlled bonding, wherein there is no damage to either the thin sheet or the carrier caused by the bonding and sufficient separation force. The thin sheet portion can be separated from the carrier, yet sufficient bonding force to hold the thin sheet against the carrier is maintained throughout processing. Referring to FIG. 6, a thin sheet of glass 20 may be bonded to glass carrier 10 by bonding area 40. In the bonding area 40, the carrier 10 and the thin sheet 20 are covalently bonded to each other so that they act as a monolith. Moreover, there is a controlled bonding area 50 with a perimeter 52, where the carrier 10 and the thin sheet 20 are connected, but even after high-temperature processing, for example processing at a temperature above 600 ° C. Will be separated from each other. Although ten controlled coupling zones 50 are shown in FIG. 6, any suitable number, including one, may be provided. As exemplified by the previous examples 2a, 2e, 3a, 3b, 4c, 4d, and 4e, the examples in Table 5, the use of a surface-modifying layer 30 that includes a heat treatment of the material and the bonding surface, A controlled bonding area 50 may be provided between the carrier 10 having a bonding surface and the thin sheet 20 having a glass bonding surface. In particular, these surface modification layers may be formed within a perimeter 52 of a controlled bonding area 50 either on the carrier 10 or on the thin sheet 20. Thus, when the article 2 is processed at an elevated temperature, either to form a covalent bond in the bonding area 40 or during device processing, the carrier 10 and the thin sheet 20 are placed in the area surrounded by the perimeter 52. A controlled bond can be provided during which the separating force (without catastrophic damage to the thin sheet or carrier) will separate the thin sheet and carrier in this area, but Thin sheets and carriers do not delaminate during processing, including sonication. Thus, the controlled bonding of the present application, as provided by the surface modification layer and any associated heat treatment, can improve the carrier concept in US Pat. In particular, while the carriers of US Pat. No. 6,052,084 have been shown to withstand FPD processing, including high temperature processing of about 600 ° C. or higher for their bonded peripheral and non-bonded central regions, ultrasonic processes, such as wet processing, Cleaning and resist removal processes remained challenging. Specifically, the pressure waves in the solution were not applied to the non-bonded region (the non-bond was described in US Pat. It has been found that thin glass introduces resonance. Standing waves can be formed in the thin glass, where these waves break the thin glass at the interface between the bonded and non-bonded regions if the ultrasonic agitation is of sufficient strength. May cause vibrations. The problem is to minimize the air gap between the thin glass and the carrier, and also to provide sufficient adhesion or controlled bonding between the carrier 20 and the thin glass 10 in these areas 50 Can eliminate it. The surface modification layer (including materials and any associated heat treatments) of the bonding surface, as exemplified by Examples 2a, 2e, 3a, 3b, 4c, 4d, 4e, and the examples in Table 5, was controlled. To avoid these unwanted vibrations in the bonding area, the bonding energy is controlled to provide sufficient bonding between the bonding surface of the glass on the thin sheet 20 and the surface of the glass on the carrier 10.

Then, during sampling of the desired portion 56 having the perimeter 57, the portion of the thin sheet 20 within the perimeter 52 will be easily separated from the carrier 10 after processing and after separation of the thin sheet along the perimeter 57. Would. Since the surface modification layers control the binding energy to prevent permanent bonding with the thin sheet carrier, they may be used in processes where the temperature is above 600 ° C. Of course, these surface modified layers will control the binding surface energy during processing at temperatures above 600 ° C., but they will require a combination of thin sheets and supports that can withstand processing at lower temperatures. It may also be used for manufacturing and for such lower temperature applications. Further, if the thermal processing of the article does not exceed 400C, Examples 2c, 2d, 4b, Examples in Tables 7-11 (including those discussed as alternatives to the examples in Table 10), Examples 12a, 12b, 12c , 12 g, 12 g, and the surface-modified layer which is illustrated by way of example in surface treatment with only O _2, - in some cases, depending on the other process requirements - similarly used to control the binding surface energy You may.

Providing a bonding area A third use of controlled bonding by a surface modifying layer (including heat treatment of the material and any associated bonding surfaces) is to provide a bonding area between the glass carrier and a thin sheet of glass. To provide. Referring to FIG. 6, a thin sheet of glass 20 may be bonded to glass carrier 10 by bonding area 40.

  In one embodiment of the third use, the bonding area 40, carrier 10 and thin sheet 20 may be covalently bonded to each other such that they act as a monolith. Moreover, there is a controlled bonding area 50 with a perimeter 52, where the carrier 10 and the thin sheet 20 are bonded to each other sufficiently to withstand the processing, but still high-temperature processing, for example above 600 ° C. Separation of the thin sheet from the carrier is possible even after processing at temperatures of. Thus, the surface modified layer 30 (heat treatment of the material and the bonding surface) as illustrated by the previous examples 1a, 1b, 1c, 2b, 2c, 2d, 4a, 4b, 12d, 12e, 12f, 12h, and 12i ) May be used to provide a bonding area 40 between the carrier 10 and the thin sheet 20. In particular, these surface modification layers and heat treatment may occur outside the perimeter 52 of the controlled bonding area 50 either on the carrier 10 or on the thin sheet 20. Thus, if the article 2 is processed at an elevated temperature or treated at an elevated temperature to form a covalent bond, the carrier and the thin sheet 20 will be in the bonding area 40 outside the area surrounded by the perimeter 52. Combine with each other. Then, if it is desired to dice the thin sheet 20 and the carrier 10 during the sampling of the desired portion 56 with the perimeter 57, these surface modification layers and heat treatment will be carried out if the thin sheet 20 and the carrier 10 are monolithic in this area. The thin sheet 20 and carrier 10 may be separated along line 5 as they are covalently bonded to act as Since the surface modification layers provide a permanent covalent bond with the thin sheet carrier, they may be used in processes where the temperature is above 600 ° C. In addition, if the thermal processing of the article, or the initial formation of the bonding area 40, is above 400 ° C. but below 600 ° C., the surface modification layer, as exemplified by the material and heat treatment in Example 4a, is the same. It may be used as follows.

In a second embodiment of the third use, in the bonding area 40, the carrier 10 and the thin sheet 20 may be bonded to each other by a controlled bonding through the various surface modification layers described above. In addition, there is a controlled bonding area 50 with a perimeter 52, where the carrier 10 and the thin sheet 20 are bonded to each other sufficiently to withstand the processing, and still high-temperature processing, e.g. Even after processing at the above temperatures, separation of the thin sheet from the carrier is possible. Thus, if the processing is performed at a temperature up to 600 ° C. and it is desirable to have no permanent or covalent bonds in the area 40, the examples 2e, 3a, 3b, 4c, 4d, 4e of the preceding examples and Table 5 The bonding area 40 between the glass bonding surface of the carrier 10 and the glass bonding surface of the thin sheet 20 using the surface modification layer 30 (including heat treatment of the material and bonding surface) as exemplified by an example. May be provided. In particular, these surface modification layers and heat treatment may be formed outside the perimeter 52 of the controlled bonding area 50 and may be formed either on the carrier 10 or on the thin sheet 20. The controlled bonding area 50 may be formed with the same or a different surface modification layer as formed in the bonding area 40. Alternatively, if the processing only takes place at temperatures up to 400 ° C. and it is desirable to have no permanent or covalent bonds in area 40, the previous examples 2c, 2d, 2e, 3a, 3b, 4b, 4c, 4d, 4e, the example of Table 5, (including examples discussed as an alternative example of Table 10) example Table 7-11 example 12a, 12b, 12c, 12 g, 12 g, and O ₂ only by surface treatment The bonding area between the glass bonding surface of the carrier 10 and the glass bonding surface of the thin sheet 20 using a surface modifying layer 30 (including heat treatment of the material and bonding surface) as exemplified by the example of Forty may be provided.

  Instead of controlled bonding in area 50, there may be unbonded areas in area 50, where the unbonded areas are areas with increased surface roughness as described in US Pat. Or may be provided by a surface modification layer as exemplified by Example 2a.

A fourth use of controlled bonding in the manner described above for bulk annealing or bulk processing relates to bulk annealing of a stack of glass sheets. Annealing is a thermal process for achieving glass compaction. Consolidation involves reheating the glass body to a temperature below the softening point of the glass, but above the maximum temperature reached during subsequent processing steps. This achieves structural rearrangement and dimensional relaxation in the glass before processing, rather than during subsequent processing. Subsequent pre-processing anneals are necessary, as in the manufacture of flat panel display devices, where structures made from many layers need to be aligned with very stringent precision, even after exposure to high temperature environments. It is beneficial to maintain accurate alignment and / or flatness in the glass body during subsequent processing. If the glass is consolidated in one high temperature process, the layers of the structure deposited on the glass prior to the high temperature process may not be exactly aligned with the layers of the structure deposited after the high temperature process.

  Compacting glass sheets in a laminate is economically attractive. However, this requires that something be sandwiched between adjacent sheets or that they be separated to avoid sticking. At the same time, it is beneficial to keep the sheets extremely flat and of optical quality or a clean surface finish. Moreover, for certain laminates of glass sheets, e.g., low surface area sheets, the glass sheets "stick" together during the annealing process so that the glass sheets can be easily moved as a unit without the need for separation. It may be beneficial to separate the glass sheets from each other (eg, by peeling) after the annealing process so that they can be used individually. Alternatively, selected sheets of glass sheets are prevented from permanently bonding with each other, while other sheets of glass sheets, or portions of those other glass sheets, e.g. It may be beneficial to anneal the stack of glass sheets, which will bond together. As yet another alternative, it may be beneficial to laminate the glass sheets so as to selectively and permanently bond together around a selected adjacent pair of sheets in the laminate. Using the above-described manner of controlling the bonding between the glass sheets, the aforementioned bulk annealing and / or selective bonding will be achieved. To control bonding at any particular interface between adjacent sheets, a surface modification layer may be used on at least one of the major surfaces facing that interface.

  One embodiment of a stack of glass sheets suitable for bulk annealing or permanent bonding in selected areas (eg, surroundings) is described with reference to FIGS. FIG. 7 is a side view of a laminate 760 of glass sheets 770-772, and FIG. 8 is an exploded view for further explanation purposes.

  The glass sheet laminate 760 may include glass sheets 770-772 and a surface modification layer 790 to control the bonding between the glass sheets 770-772. Moreover, the laminate 760 may include cover sheets 780, 781 located at the top and bottom of the laminate, and may include a surface modifying layer 790 between the cover and an adjacent glass sheet. .

  As shown in FIG. 8, each of glass sheets 770 to 772 has a first main surface 776 and a second main surface 778. The glass sheet may be made from any suitable glass material, for example, aluminosilicate glass, borosilicate glass, or aluminoborosilicate glass. Moreover, the glass may contain alkali or be non-alkali. Each of the glass sheets 770-772 may be of the same composition, or the sheets may be of different compositions. Further, the glass sheet may be of any suitable type. That is, for example, the glass sheets 770 to 772 may be all the carriers as described above, may be all the thin sheets as described above, or may be the carriers and the thin sheets alternately. If bulk annealing requires a different time-temperature cycle for the carrier than for the thin sheet, it is beneficial to have a laminate of the carrier and a separate laminate of the thin sheet. Alternatively, with the proper surface modification layer material and arrangement, having a stack of alternating carriers and thin sheets, the desired pair of carriers and thin sheets, i.e., the pair forming the article, is then It would be desirable to maintain the ability to separate adjacent articles from one another while simultaneously being covalently bonded together for processing. Furthermore, there may be any suitable number of glass sheets in the laminate. That is, although only three glass sheets 770-772 are shown in FIGS. 7 and 8, any suitable number of glass sheets may be included in laminate 760.

  In any particular laminate 760, any one glass sheet may have one surface modified layer without a surface modified layer, or may have two surface modified layers. For example, as shown in FIG. 8, sheet 770 has no surface modification layer, sheet 771 has one surface modification layer on second main surface 778, and sheet 772 has one surface modification layer. It has two surface modified layers 790 such that the quality layer is on each of the major surfaces 776, 778.

  The cover sheets 780, 781 may be made of any material that suitably withstands the time-temperature cycling for a given process (not only with respect to time and temperature, but also with respect to other relevant considerations such as, for example, outgassing). You may. It may be convenient for the cover sheet to be manufactured from the same material as the glass sheet being processed. If the cover sheets 780, 781 are present and are of a material that undesirably bonds to the glass sheet when the laminate is subjected to a predetermined time-temperature cycle, the glass sheet 771 and the cover sheet 781, And / or between the glass sheet 772 and the cover sheet 780, a surface modifying layer 790 may be provided. The surface modifying layer, if present between the cover and the glass sheet, may be on the cover (as shown with respect to cover 781 and adjacent sheet 771) or on the glass sheet (cover 780 and adjacent sheet 772). , Or as shown on both the cover and the adjacent sheet (not shown). Alternatively, if the cover sheets 780, 781 are of a material that does not bond with the adjacent sheets 772, 771, then the surface modification layer 790 need not be present between them.

  There is an interface between adjacent sheets in the laminate. For example, an interface is defined between adjacent ones of the glass sheets 770-772, i.e., there is an interface 791 between sheet 770 and sheet 771, and there is an interface 792 between sheet 770 and sheet 772. In addition, if the cover sheets 780, 781 are present, there is an interface 793 between the cover 781 and the sheet 771, and an interface 794 between the sheet 772 and the cover 780.

  The surface modification layer 790 is used to control bonding at predetermined interfaces 791, 792 between adjacent glass sheets or at predetermined interfaces 793, 794 between glass sheets and cover sheets. Is also good. For example, as shown, at each of the interfaces 791 and 792, a surface modification layer 790 exists on at least one of the main surfaces facing the interface. For example, for interface 791, the second major surface 778 of glass sheet 771 includes a surface modification layer 790 to control the bond between sheet 771 and adjacent sheet 770. Although not shown, the first major surface 776 of sheet 770 may also have a surface modifying layer 790 thereon to control bonding with sheet 771, i.e., any particular interface There may be a surface modification layer on each of the main surfaces facing the.

  A particular surface modification layer 790 at any given interface 791-794 (and any associated surface modification treatment-eg, heat treatment of a particular surface before applying the particular surface modification layer to that surface; Or surface heat treatment of the surface to which the surface modification layer will come into contact) controls the bonding between adjacent sheets, thereby achieving the desired result for a given time-temperature cycle in which the laminate 760 is applied. May be selected for its major surfaces 776, 778 facing the predetermined interfaces 791-794.

If it is desired to bulk anneal the stack of glass sheets 770-772 at temperatures up to 400 ° C. and separate each of the glass sheets from one another after the annealing process, then at any particular interface, eg, interface 791 2a, 2c, 2d, 2e, 3a, 3b, 4b-4e, examples in Table 5, examples in Tables 7-11 (discussed as alternatives to the examples in Table 10) including examples which are), example 12a, 12b, 12c, 12 g, 12 g, or would O ₂ only can be controlled using the material according to any one of the examples of the surface treatment by. More specifically, the first major surface 776 of sheet 770 will be treated as a "thin glass" in Tables 2-4, while the second major surface 778 of sheet 771 will be treated as a "thin glass" in Tables 2-4. It will be treated as a "carrier". The reverse is also true. An appropriate time-temperature cycle with a temperature up to 400 ° C. is then performed to achieve the required time-temperature for the entire laminate, the desired degree of compaction, the number of sheets in the laminate, and the sheets. Could be selected based on the size and thickness of the

  Similarly, if it is desired to bulk anneal the stack of glass sheets 770-772 at a temperature up to 600 ° C. and separate each of the glass sheets from one another after the annealing process, then any particular interface, for example, Bonding at interface 791 can be controlled using the materials according to Examples 2a, 2e, 3a, 3b, 4c, 4d, 4e, or any one of the examples in Table 5, with any associated surface treatment. Would. More specifically, the first major surface 776 of sheet 770 will be treated as a "thin glass" in Tables 2-4, while the second major surface 778 of sheet 771 will be treated as a "thin glass" in Tables 2-4. It will be treated as a "carrier". The reverse is also true. An appropriate time-temperature cycle with a temperature up to 600 ° C. is then performed to achieve the required time-temperature for the entire laminate, the desired degree of compaction, the number of sheets in the laminate, and the sheets. Could be selected based on the size and thickness of the

Furthermore, by appropriately configuring the sheet stack and the surface modification layer between each pair of sheets, bulk annealing and bulk article formation can be performed. If it is desired to bulk anneal the stack of glass sheets 770-772 at temperatures up to 400 ° C. and then covalently bond pairs of adjacent sheets together to form article 2, to control the bonding In the meantime, appropriate materials and associated surface treatments could be used. For example, around (or at any other desired bonding area 40), the bonding at the interface between a pair of glass sheets to be formed into the article 2, for example, sheets 770 and 771, is (i) the bonding of Around (or at any other desired bonding area 40), along with any associated surface treatments, Examples 2c, 2d, 4b, Examples of Tables 7-11 (including examples discussed as alternatives to the examples of Table 10) ), example 12a, 12b, 12c, 12 g, 12 g, or O ₂ material according to any one of the examples of the surface treatment with only; and (ii) interior region of the sheet 770, 771 (i.e., (i) was treated in the Examples 2a, 2e, 3a, 3b, along with any relevant surface treatments, in the surrounding internal area or in the desired controlled bonding area 50 where separation of one sheet from the other is desired. , 4c, 4d, 4e, or material according to any one of the examples in Table 5; could be controlled using. In this case, device processing in the controlled bonding area 50 would then be possible at temperatures up to 600 ° C.

  Materials and heat treatments could be appropriately selected for compatibility with each other. For example, any of the materials 2c, 2d, or 4b can be used in the bonding area 40 with the material according to Example 2a for a controlled bonding area. Alternatively, the heat treatment of the bonding area and the controlled bonding area could be appropriately controlled to minimize the effect of the heat treatment in one area, which would adversely affect the desired degree of bonding in adjacent areas.

  After properly selecting the surface modification layer 790 and the associated heat treatment for the glass sheets in the laminate, properly aligning the sheets into a laminate and then heating them to 400 ° C. to make them permanent with each other Would be able to bulk anneal all of the sheets in the stack without bonding. The laminate can then be heated to 600 ° C. to form covalent bonds in the desired bonding areas of adjacent pairs of sheets to form an article 2 having a pattern of bonding areas and controlled bonding areas. Will. The bonding at the interface between one pair of sheets to be covalently bonded by the bonding area 40 to form an article 2 and another pair of such sheets forming another adjacent article 2 The two would not be covalently linked to each other, which could be controlled by the materials of Examples 2a, 2e, 3a, 3b, 4c, 4d, 4e, the examples of Table 5 and the associated heat and heat. In this same manner of controlling the bond between adjacent articles, the bond between the article and any coversheet present in the laminate could be controlled.

  Furthermore, similarly to the above, it is also possible to form the article 2 collectively from the laminate 760 without previously annealing the same laminate 760. Alternatively, the sheets may be annealed separately or in different laminates before the sheets are configured for controlled bonding in the laminate as desired to produce the article together, where Could be separated from The bulk anneal is simply omitted from the manner described immediately above, where the bulk anneal is then formed together from one and the same laminate.

  Only the manner in which bonding at interface 791 is controlled has been described in detail above, but of course, the same may be done at interface 792, or-if there are more than three glass sheets in the laminate, or desirable for glass sheets. The same may be done for any other interface that would be present in a particular laminate, such as when there is a cover sheet that would bond without. Furthermore, the same manner of controlling binding may be used for any interface 791, 792, 793, 794 present, but different ones of the above-described manner of controlling binding may be used for different interfaces to provide the desired interface. The same or different results may be produced with respect to the type of coupling.

  In the above process of the bulk anneal or in forming the article 2 together, HMDS is used as a material to control the bonding at the interface and if the HMDS is exposed to the periphery of the laminate, If it is desired to prevent covalent bonding, heating above about 400 ° C. should be performed in an oxygen-free atmosphere. That is, if the HMDS is exposed to an amount of oxygen in the atmosphere that is sufficient to oxidize the HMDS (at a temperature greater than about 400 ° C.), any bond in any such area where the HMDS is oxidized, It becomes a covalent bond between adjacent glass sheets. Other alkyl hydrocarbon silanes, such as ethyl, propyl, butyl, or steryl, silanes, can also be affected by exposure to oxygen at higher temperatures, for example, temperatures greater than about 400 ° C. Similarly, if other materials are used for the surface modification layer, the environment for the bulk anneal should be selected so that those materials do not degrade over the time-temperature cycle of the anneal. As used herein, anoxic will mean an oxygen concentration of less than 1000 ppm by volume, more preferably less than 100 ppm by volume.

  Once the stack of sheets has been bulk annealed, the individual sheets may be separated from the stack. Individual sheets can be treated (eg, by oxygen plasma, heating in an oxygen environment at a temperature of 400 ° C. or higher, or by chemical oxidation, SC1, or SC2) to remove the surface modification layer 790. . The individual sheets can be used as desired (eg, as a substrate for an electronic device, eg, an OLED, FPD, or PV device).

  The above-described methods of bulk annealing or bulk processing have the advantage of maintaining a clean sheet surface in an economical manner. More specifically, the sheet need not be maintained in a clean environment from start to finish, as in a lehr in a clean room. Instead, the laminate is formed in an uncontaminated environment and then processed in a standard lehr (ie, one with uncontrolled cleanliness) without the sheet surface getting particulate fouling. can do. This is because there is no fluid flow between the sheets. Thus, the sheet surface is protected from the environment in which the stack of sheets is annealed. After the anneal, the sheet stack maintains a certain degree of adhesion and still remains separable from each other when sufficient force is applied, without damaging the sheet, so that the stack of sheets is further processed ( (In the same or different facility). That is, a glass manufacturer (eg) assembles a laminate of glass sheets, anneals, and then ships the sheets as a laminate that stays together during shipment (without fear of the sheets separating during shipment). The sheets could be separated from the stack by customers who would use the sheets individually or as a smaller group upon arrival at their destination. Once separation is desired, the laminate of sheets can be processed again in a clean environment (after washing the laminate if necessary).

Example of bulk annealing A glass substrate was used as received from the fusion draw method. The glass composition produced by the fusion draw method (expressed in mol%): SiO ₂ (67.7), Al ₂ O ₃ (11.0), B ₂ O ₃ (9.8), CaO (8 .7), MgO (2.3) and SrO (0.5). Patterns were formed on seven glass substrates manufactured by the fusion draw method with a thickness of 0.7 mm and a diameter of 150 mm by a lithography method using a standard / vernier with a depth of 200 nm using HF. A 2 nm plasma-deposited fluoropolymer was coated as a surface-modifying layer on the entire bonded surface of all glass substrates, ie, coated on each surface of the substrate facing another substrate, with each sheet surface The resulting surface energy was about 35 mJ / m ² . Each of the seven coated glass substrates was placed together to form a single thick substrate (referred to as "glass laminate"). This glass laminate is heated from 30 ° C. to 590 ° C. in a 15 minute period in a tube furnace purged with nitrogen, kept at 590 ° C. for 30 minutes, and then cooled to about 230 ° C. in a 50 minute period. The glass laminate was then removed from the furnace and annealed by cooling to room temperature of about 30 ° C. in about 10 minutes. After cooling, the substrate was removed from the furnace and easily separated into individual sheets using a razor wedge (ie, the sample was not permanently bonded, globally or locally). Compression was measured on each individual substrate by comparing the glass reference to an unannealed quartz control. The individual substrates were found to have compressed about 185 ppm. The two annealing cycles described above (holding at 590 ° C./30 minutes) were performed on the two substrates as separate samples (not laminated together). The compression was measured again and it was found that the substrates further compressed by less than 10 ppm (actually from 0 to 2.5 ppm) for the second heat treatment (after the second heat treatment-the dimensions of the original glass) -The change in glass size minus the change in glass size after the first heat treatment). Thus, the inventors have determined that individual glass sheets can be coated, laminated, heat treated at elevated temperatures to achieve compaction, cooled, separated into individual sheets, and after a second heat treatment. It had a dimensional change (compared to the size after the first heat treatment) of less than 10 ppm, and even less than 5 ppm.

While the furnace in the annealing example described above was purged with nitrogen, the lehr was air-, argon-, oxygen-, CO2- _It may be purged with other gases, including ₂ or a combination thereof. Instead of an inert atmosphere, the furnace in the annealing described above may be in a vacuum environment.

  Moreover, although not shown, the glass may be annealed in spool form instead of sheet form. That is, an appropriate surface modification layer may be formed on one or both sides of the glass ribbon, and then the ribbon may be wound. The entire roll is subjected to the same processing as described above for the sheet, in which case the entire spool of glass will be annealed without a single turn of glass sticking to the adjacent one. Upon unwinding from the roll, the surface modification layer may be removed by any suitable process.

Outgassing Polymeric adhesives used in typical wafer bonding applications are typically 10-100 micrometers thick, losing about 5% of mass at or near its temperature limit. For such materials released from thick polymer films, it is easy to quantify the amount of mass loss, or outgassing, by mass spectrometry. On the other hand, outgassing from thin surface treatments as thin as 10 nm or less, for example, the surface modified layer of the plasma polymer or self-assembled monolayer described above, and a thin layer of pyrolyzed silicone oil, is more Have difficulty. For such materials, mass spectrometry is not sensitive enough. However, there are many other ways to measure outgassing.

  A first method for measuring small outgassing is based on surface energy measurements and is described with reference to FIG. To perform this test, the configuration shown in FIG. 9 may be used. A first substrate or carrier 900 having a surface modification layer to be tested thereon, ie, a surface modification layer corresponding in composition and thickness to the surface modification layer 30 to be tested, exhibits a surface 902. The second substrate or cover 910 is arranged such that its surface 912 is close to, but not in contact with, the surface 902 of the carrier 900. Surface 912 is the uncoated surface, ie, the bare surface of the material making up the cover. Spacers 920 are located at various points between the carrier 900 and the cover 910 to keep them separated from each other. The spacer 920 is thick enough to separate the cover 910 from the carrier 900 and allow the transfer of material from one to the other, but during testing, the amount of contamination from the bath atmosphere onto the surfaces 902 and 912 is reduced. Should be thin enough to be minimal. The carrier 900, the spacer 920, and the cover 910 together form a test article 901.

  Before assembling the test article 901, the surface energy of the bare surface 912 is measured, such as the surface energy of the surface 902, ie, the surface of the carrier 900 on which the surface modification layer is provided. The surface energies shown in FIG. 10 for both polar and dispersed components were measured by fitting the Wu model to the contact angles of three test liquids: water, diiodomethane and hexadecane.

After assembly, the test article 901 was placed in a heating bath 930 and heated through a time-temperature cycle. The heating is carried out at atmospheric pressure under flowing N ₂ gas flowing in the direction of arrow 940 at a flow rate of 2 liters per minute under standard conditions.

  During the heating cycle, changes in the surface 902 (including changes to the surface modified layer due to, for example, evaporation, pyrolysis, decomposition, polymerization, reaction with a carrier, and dewetting) are caused by changes in the surface energy of the surface 902. Proven. A change in the surface energy of the surface 902 itself does not necessarily mean that the surface modified layer has caused outgassing, but its properties change, for example, due to the mechanism described above, so that at that temperature, 2 shows the general instability of the material. Therefore, the smaller the change in the surface energy of the surface 902, the more stable the surface modified layer. On the other hand, as the surface 912 is close to the surface 902, any outgassed material from the surface 902 is collected on the surface 912 and changes the surface energy of the surface 912. Accordingly, a change in surface energy of surface 912 is a proxy for outgassing of the surface modified layer present on surface 902.

Thus, one test of outgassing uses the change in surface energy of the cover surface 912. For more information, 10 mJ / m ² or more - the surface 912 of the - if there is a change in surface energy, therefore, there is a gas discharge. Changes in surface energy of this magnitude are consistent with contamination that can result in loss of film adhesion or degradation of material properties and device performance. A change in surface energy of 5 mJ / m ² or less is close to reproducibility of surface energy measurement and non-uniformity of surface energy. This small change is consistent with minimal outgassing.

In the test that produced the results of FIG. 10, the carrier 900, cover 910, and spacer 920 were "Eagle XG," an alkali-free aluminoborosilicate display glass obtained from Corning Incorporated, Corning, NY. "Made from glass, but need not be. The carrier 900 and the cover 910 had a diameter of 150 mm and a thickness of 0.63 mm. In general, carrier 910 and cover 920 are made of the same material as carrier 10 and thin sheet 20, respectively, and it is desirable to perform a gas release test on them. During this test, the silicon spacer was 0.63 mm thick, 2 mm wide and 8 cm long, thereby creating a gap of 0.63 mm between surfaces 902 and 912. During this test, the bath 930 was incorporated into the MPT-RTP600s high-speed heat treatment apparatus, which periodically raised and lowered the temperature from room temperature to the test limit temperature at a rate of 9.2 ° C. per minute, and referred to the graph “Annealed It was held at the test limit for the various times indicated in "Time" and then cooled at 200 ° C. at furnace speed. After the furnace had cooled to 200 ° C., the test article was removed and the surface energy of each surface 902 and 912 was measured again after the test article had cooled to room temperature. Thus, as an example, data was collected on material # 1 using the data on the change in surface energy of the cover, tested at line 1003 to a critical temperature of 450 ° C., as follows. The data points at 0 minutes indicate a surface energy of 75 mJ / m ² (millijoules per square meter), which is the surface energy of bare glass, ie, no time-temperature cycling has been performed. The data points at 1 minute indicate the surface energy measured after a time-temperature cycle performed as follows: Article 901 (with material # 1 used as a surface modification layer on carrier 900 representing surface 902) the room temperature and placed in a heating bath 930 at atmospheric pressure; this vessel, while flowing 2 liters per minute of N ₂ gas at standard conditions, test limit temperature of 450 ° C. at a rate of 9.2 ° C. And held at the test limit temperature of 450 ° C. for 1 minute; the vessel was then cooled at a rate of 1 ° C. per minute to 300 ° C., then the article 901 was removed from the vessel 930; cooling the article to room temperature (N ₂ not flow atmosphere); then, the surface energy of the surface 912 was measured and plotted as a point of 1 minute line 1003. Then, the remaining data points for material # 1 (lines 1003, 1004), as well as material # 2 (lines 1203, 1204), material # 3 (lines 1303, 1304), material # 4 (lines 1403, 1404), material # Data points for 5 (lines 1503, 1504), material # 6 (lines 1603 and 1604), and material # 7 (lines 1703, 1704) were tested at either 450 ° C. or 600 ° C., as appropriate. It was similarly determined by the fraction of the annealing time corresponding to the holding time at the limit temperature. Lines 1001, 1002, 1201, 1202, 1301, 1302, 1401, 1402, 1501, 1502, 1601, 1602, 1701, 1701, 1001, 1002, 1201, 1202, 1301, 1302, 1401, 1401, 1401, 1601, 1701, and And 1702 were determined similarly, except that the surface energy of surface 902 was measured after each time-temperature cycle.

  The above described assembly process and time-temperature cycling were performed on seven different materials described below. The results are shown graphically in FIG. Of the seven types of materials, materials # 1 to # 4 and # 7 correspond to the above-described surface modified layer materials. Materials # 5 and # 6 are comparative examples.

Material # 1 is a CHF ₃ -CH ₄ plasma polymerized fluoropolymers. This material is consistent with the surface modified layer in Example 3b above. As shown in FIG. 10, lines 1001 and 1002 indicate that the surface energy of the carrier did not change significantly. Therefore, this material is very stable at temperatures between 450 ° C and 600 ° C. Moreover, as shown by lines 1003 and 1004, the surface energy of the cover did not change significantly, ie, the change was less than 5 mJ / m ² . Therefore, there was no outgassing for this material from 450 ° C. to 600 ° C.

Material # 2 is a self-assembled monolayer (SAM) of phenylsilane deposited from a 1% solution of phenyltriethoxysilane in toluene and cured in a vacuum oven at 190 ° C. for 30 minutes. This material is consistent with the surface modified layer in Example 4c above. As shown in FIG. 10, lines 1201 and 1202 indicate that the surface energy on the carrier changes somewhat. As mentioned above, this indicates some change in the surface modification layer, and material # 2 is relatively somewhat less stable than material # 1. However, as shown by lines 1203 and 1204, the change in surface energy of the cover was 5 mJ / m ² or less, indicating that changes to the surface modified layer did not result in outgassing.

Material # 3 is a SAM of pentafluorophenylsilane deposited from a 1% solution of pentafluorophenyltriethoxysilane in toluene and cured in a vacuum oven at 190 ° C. for 30 minutes. This material is consistent with the surface modified layer in Example 4e above. As shown in FIG. 10, lines 1301 and 1302 indicate that the surface energy on the carrier changes somewhat. As described above, this indicates some change in the surface modification layer, and material # 3 is relatively somewhat less stable than material # 1. However, as shown by lines 1303 and 1304, the change in surface energy of the cover was less than 5 mJ / m ² , indicating that changes to the surface modified layer did not result in outgassing.

Material # 4 is hexamethyldisilazane (HMDS) deposited from steam in a YES HMDS oven at 140 ° C. This material is consistent with the surface modified layer in Example 2b of Table 2 above. As shown in FIG. 10, lines 1401 and 1402 indicate that the surface energy on the carrier changes somewhat. As mentioned above, this indicates some change in the surface modification layer, and material # 4 is relatively somewhat less stable than material # 1. Moreover, the change in surface energy of the support for material # 4 is greater than the change in either of materials # 2 and # 3, and relatively, material # 4 is somewhat more unstable than materials # 2 and # 3. Indicates that there is. However, as shown by lines 1403 and 1404, the change in surface energy of the cover was less than 5 mJ / m ² , and changes to the surface modified layer did not result in outgassing that affected the surface energy of the cover. Indicates that However, this is consistent with the manner in which HMDS outgases. That is, HMDS outgases ammonia and water, which will not affect the surface energy of the cover and will not affect the manufacturing equipment and / or processing of some molecular components. On the other hand, if the products of outgassing are trapped between the thin sheet and the carrier, there may be other problems, as shown below for the second outgassing test.

Material # 5 is a SAM of glycidoxypropylsilane deposited from a 1% solution of glycidoxypropyltriethoxysilane in toluene and cured in a vacuum oven at 190 ° C. for 30 minutes. This is the material of the comparative example. There is relatively little change in the surface energy of the carrier, as shown by lines 1501 and 1502, but there is a significant change in the surface energy of the cover, as shown by lines 1503 and 1504. That is, the material # 5 is relatively stable on the support surface, it is, in fact, a significant amount of material on the cover surface outgassing, thereby, the surface energy of the cover is changed 10 mJ / m ² or more . The surface energy at the end of 10 minutes at 600 ° C. is within 10 mJ / m ² from the beginning, but the change during that period exceeds 10 mJ / m ² . See, for example, 1 and 5 minute data points. Without intending to be bound by theory, it is believed that the slight increase in surface energy for 5 to 10 minutes was due to some of the outgassed material decomposing and flaking off the cover surface.

Material # 6 dispensed 5 ml of Dow Corning 704 diffusion pump oil, tetramethyltetraphenyltrisiloxane (obtained from Dow Corning) onto a carrier, which was placed on a 500 ° C. hot plate in air for 8 minutes. DC704 silicone coating prepared by placing. Completion of sample preparation is indicated by the end of visible smoke. After preparing the samples in the manner described above, the gas release test described above was performed. This is the material of the comparative example. As shown in FIG. 10, lines 1601 and 1602 show some changes in surface energy on the carrier. As mentioned above, this indicates some change in the surface modification layer, and material # 6 is relatively less stable than material # 1. Moreover, as shown by lines 1603 and 1604, the change in surface energy of the cover is greater than 10 mJ / m ² , indicating significant outgassing. More specifically, at the test limit temperature of 450 ° C., the 10 minute data points show a decrease in surface energy of about 15 mJ / m ² and a greater decrease in surface energy at 1 minute and 5 minutes. I have. Similarly, for a change in cover surface energy during cycling at a test limit temperature of 600 ° C., the decrease in cover surface energy is about 25 mJ / m ² at the 10 minute data point and somewhat greater at 5 minutes. One minute was somewhat small. In summary, however, this material exhibited a significant amount of outgassing over the entire range of the test.

Material # 7 is a CH ₄ -H ₂ plasma deposition polymer, then a polymer that has been processed by the short-term N ₂ -O _2, and N ₂ plasma. This material is similar to the surface modified layer in the example of Table 11 above. As shown in FIG. 10, lines 1701 and 1702 indicate that the surface energy of the carrier did not change significantly. Therefore, this material is very stable at temperatures between 450 ° C and 600 ° C. In addition, as shown by lines 1703 and 1704, the surface energy of the cover did not change significantly, ie, the change was less than 5 mJ / m ² . Therefore, there was no outgassing for this material from 450 ° C. to 600 ° C.

  Importantly, for materials # 1 to 4 and 7, the surface energy over the time-temperature cycle is such that the cover surface remains surface energy consistent with the surface energy of bare glass, i.e., the carrier surface Outgassing material is not collected. As shown with respect to Table 2, in the case of material # 4, the manner in which the surface of the carrier and the thin sheet was prepared is such that the article (the thin sheet bonded together with the carrier by the surface modification layer) withstands FPD processing It makes a big difference whether or not. Thus, although the example of material # 4 shown in FIG. 10 may not outgas, this material may or may not withstand the 400 ° C. or 600 ° C. test as described with respect to the discussion in Table 2. Maybe not.

  A second method of measuring small outgassing is based on an assembled article, i.e., an article in which a thin sheet is bonded to a carrier via a surface modification layer, to determine the outgassing percentage of the cell area. Use change. That is, during heating of the article, bubbles formed between the carrier and the thin sheet indicate outgassing of the surface modified layer. As mentioned above for the first outgassing test, it is difficult to measure outgassing of a very thin surface modified layer. In this second test, outgassing under the thin sheet will be limited by the strong adhesion between the thin sheet and the carrier. Nevertheless, layers less than 10 nm thick (eg, plasma polymerized materials, SAMs, and pyrolyzed silicone oil surface treatments) will still produce bubbles during heat treatment, despite less absolute mass loss. . The formation of bubbles between the thin sheet and the carrier will create problems with pattern generation, photolithographic processing, and / or alignment during device processing on the thin sheet. Moreover, bubbling at the interface of the bonding area between the thin sheet and the carrier will create problems with process fluids from certain processes that contaminate downstream processes. Changes in bubble area% of 5 or more are significant and indicate outgassing and are undesirable. On the other hand, a change in bubble area% of 1 or less is insignificant and indicates no outgassing.

The average cell area of bonded thin glass in a class 1000 clean room for manual bonding is 1%. The% air bubbles in the bound carrier is a function of the cleanliness of the carrier, thin glass sheet, and surface treatment. Because these initial defects serve as nucleation sites for bubble growth after heat treatment, any change in bubble area during heat treatment of less than 1% is within the variability of sample preparation. To perform this test, a first scan image of the area where the thin sheet and carrier were bonded immediately after bonding was created using a commercially available desktop scanner (Epson Expression 10000XL Photo) equipped with a transparent unit. The parts were scanned using standard Epson software using 508 dpi (50 micrometers / pixel) and 24-bit RGB. The image processing software first combines the images of the different sections of the sample into a single image, if necessary, and removes scanner artifacts (using a calibration reference scan performed without a sample in the scanner). To prepare the image. The combined area is then analyzed using standard image processing techniques such as thresholding, filling, erosion / dilation, and blob analysis. The latest Epson Expression 11000XL Photo may be used as well. In the transmission mode, the bubbles in the coupling area are visible in the scanned image and the value of the bubble area can be determined. The cell area is then compared to the total bonded area (ie, the total overlap area between the thin sheet and the carrier) to calculate the area% of the cells in the bonded area relative to the total bonded area. Then, over the sample to 10 minutes, 300 ° C., at 450 ° C., and 600 ° C. of the test limit temperature, under N ₂ atmosphere, a heat treatment in MPT-RTP600s Rapid Thermal Processing System. Specifically, the time-temperature cycle performed included: placing the article in a heating bath at room temperature and atmospheric pressure; the bath was then heated to the test limit temperature at a rate of 9 ° C. per minute; The bath was held at the test limit for 10 minutes; then, the bath was cooled at furnace speed to 200 ° C .; the article was removed from the bath and allowed to cool to room temperature; then the article was scanned a second time with an optical scanner. Did. The% bubble area from the second scan was then calculated as above and compared to the% bubble area from the first scan to determine the change in% bubble area (Δ% bubble area). As mentioned above, a change in bubble area of 5% or more is significant and indicates outgassing. Certain changes in bubble area% were selected as metrics due to variations in the original bubble area%. That is, most surface modified layers have about 2% cell area in the first scan after thin sheets and carriers have been prepared and before bonding, due to handling and cleanliness. Have. However, variations may occur between materials. The same set of materials # 1-7 described for the first outgassing test method was used again in this second outgassing test method. Of these materials, materials # 1-4 exhibited about 2% cell area in the first scan, whereas materials # 5 and # 6 showed significantly larger cell areas in the first scan. That is, about 4% was shown.

  The results of the second outgassing test will be described with reference to FIGS. FIG. 11 shows the gas release test results of materials # 1 to # 3 and # 7, while FIG. 12 shows the gas release test results of materials # 4 to # 6.

  The results for material # 1 are shown in FIG. 11 as square data points. As can be seen, the change in bubble area% was nearly zero for the 300 ° C, 450 ° C, and 600 ° C test limit temperatures. Therefore, material # 1 does not exhibit outgassing at these temperatures.

  The results for material # 2 are shown in FIG. 11 as diamond data points. As can be seen, the change in bubble area% is less than 1 for the 450 ° C. and 600 ° C. test limit temperatures. Thus, material # 2 does not exhibit outgassing at these temperatures.

  The result for material # 3 is shown in FIG. 11 as triangular data points. As can be seen, similar to the result for Material # 1, the change in bubble area% was nearly zero for the 300 ° C, 450 ° C, and 600 ° C test limit temperatures. Therefore, material # 3 does not exhibit outgassing at these temperatures.

  The result for material # 7 is shown in FIG. 11 as a cross data point. As can be seen from the figures, the change in bubble area% is almost zero for the 300 ° C and 450 ° C test limit temperatures. Therefore, material # 7 does not exhibit outgassing at these temperatures. For a test limit temperature of 600 ° C., material # 7 shows a change in bubble area% of less than 2. Thus, material # 7 exhibits at most minimal outgassing at this temperature.

  The result for material # 4 is shown in FIG. 12 as circular data points. As can be seen, the change in bubble area% is nearly zero for the 300 ° C test limit, but close to 1% for some samples at the 450 ° C and 600 ° C test limit, for other samples of the same material. For the sample, it is about 5% at 450 ° C. and 600 ° C. test limit temperature. The results for material # 4 are very inconsistent, depending on the manner in which the thin sheet and carrier surfaces were prepared for bonding with the HMDS material. The manner in which the sample functions, depending on the manner in which the sample is prepared, is consistent with the example of this material discussed above with respect to Table 2, and the related discussion. It was noted that for this material, for the test limit temperatures of 450 ° C. and 600 ° C., samples with near 1% change in bubble area% were unable to separate the thin sheet from the carrier by the separation test described above. . That is, the strong adhesion between the thin sheet and the carrier seems to have limited the generation of bubbles. On the other hand, samples with a change in bubble area% close to 5% allowed the thin sheet to be separated from the carrier. Thus, the sample that did not outgas has the undesirable consequence of increased adhesion (hindering the detachment of the thin sheet from the carrier) after temperature treatment of sticking the carrier and the thin sheet together, whereas the thinner Samples that allowed for removal of the sheet and carrier had undesirable results of outgassing.

  The results for material # 5 are shown in FIG. 12 as triangular data points. As can be seen from the figure, the change in bubble area% is about 15% for the test limit temperature of 300 ° C., which is much higher for the higher test limit temperatures of 450 ° C. and 600 ° C. Thus, material # 5 exhibits significant outgassing at these temperatures.

  The result for material # 6 is shown in FIG. 12 as square data points. As can be seen from the figure, the change in bubble area% exceeds 2.5% for the 300 ° C test limit temperature and 5% for the 450 ° C and 600 ° C test limit temperatures. Thus, material # 6 exhibits significant outgassing at the 450 ° C. and 600 ° C. test limit temperatures.

Bonding of polymer surface to glass surface Display has been demonstrated on polymer sheets such as polyethylene naphthalate (PEN), polyethylene terephthalate (PET) and polyimide (PI), where device fabrication is laminated to a glass carrier It was a sheet-to-sheet by PEN. Layers of polymeric adhesive up to 100 micrometers thick are commonly used to laminate PEN and PET on glass supports for sheet-to-sheet processing. The mass loss of these adhesives during device processing typically exceeds 1%, which creates challenges for contamination due to solvent outgassing. Moreover, complete removal of the adhesive is difficult and, therefore, the glass carrier is generally not reused.

  In the present application, a thin surface-modifying layer is used to form a controlled temporary bond that is strong enough to withstand TFT processing but weak enough to allow delamination, and is used with a glass carrier. It describes forming a moderate bond with the polymer sheet. Thermal, vacuum, solvent and acidic, and ultrasonic flat panel display (FPD) processes require the robust bonding of a thin polymeric sheet bonded to a carrier, but the surface modification of the present invention discussed herein Various of the layers were able to achieve such controlled bonding for processing thin sheets of polymer on a glass carrier. Furthermore, the controlled bonding allows the polymer thin sheet to be removed from the carrier without causing catastrophic damage to either the polymer thin sheet or the glass carrier, thereby providing a reusable glass A carrier could be provided.

  There are three transistor technologies in mass production for FPD backplane fabrication: amorphous silicon (aSi) bottom gate TFT, polycrystalline silicon (pSi) top gate TFT, and amorphous oxide (IGZO) bottom gate TFT . All of these techniques require high temperature processing steps in excess of 300 ° C. This requirement of a substrate to allow high temperature processing, as well as requirements for chemical, mechanical and vacuum compatibility, have been the main limitations on the industrialization of flexible displays on existing flexible substrates such as polymers. The general process typically begins with the cleaning of the polymer substrate in a hot alkaline solution by ultrasonic or megasonic agitation, followed by a rinse with deionized water. Device structures are manufactured in a number of subtractive cycles of material deposition and photolithographic patterning followed by material etching. Metal, dielectric, and semiconductor materials are deposited by vacuum processes, such as sputtering of metals, transparent conductive oxides and oxide semiconductors, chemical vapor deposition (CVD) of amorphous silicon, silicon nitride, and silicon dioxide at elevated temperatures. You. Laser and strobe anneals allow p-Si crystallization without excessive heating of the substrate, but uniformity is a challenge and poor performance compared to glass substrates. Patterns are formed on the layers by photolithographic patterning of polymer resist, etching, and subsequent resist removal. Both vacuum plasma (dry) etching and acidic wet etching processes are used. In FPD processing, the photoresist is typically removed with a hot solvent, typically with ultrasonic or megasonic agitation.

  Removal of the thick layer of adhesive hinders the reusability of the carrier. For polymeric adhesives useful for FPD processing, the adhesive must have good chemical durability in solvents, strong acids, and strong bases. However, these same properties make removal difficult. For layers having a thickness of up to 100 micrometers, a plasma process is not practical for removing those layers. A major challenge for organic thin film transistor fabrication is the lamination of thin polymer sheets on a carrier.

  The present application describes a method of controlling and temporarily bonding a polymer sheet to a glass carrier for an FPD process, and a reusable glass carrier for sheet-to-sheet processing of thin polymer substrates. Has been described. The formation of the surface modified layer on the glass carrier results in a temporary bond of moderate adhesion between the thin polymeric sheet and the carrier. This moderate adhesion is achieved by optimizing the contribution of Van der Waals and covalent attraction energy to the total adhesion energy, which is controlled by adjusting the polar and non-polar surface energy components of the thin sheet and carrier. This moderate bond is strong enough to withstand FPD processing (including wet, ultrasonic, vacuum, and thermal processes), yet allows the polymer sheet to be peeled from the carrier by applying sufficient peel force You can leave it. The surface modified layer has a thickness of less than 1 micrometer and is easily removed in oxygen plasma, so it is possible to remove devices manufactured on a thin polymer sheet and reuse the carrier by peeling. is there.

  The following advantages of using a thin surface-modifying layer to create a modest bond between the thin polymeric sheet and the glass carrier will be obtained.

  (1) Because the amount of material used to bond the thin polymeric sheet to the carrier is reduced by about 100 times compared to commercial adhesives, the outgassing and contaminant absorption potential and downstream The possibility of contaminating the process is reduced.

  (2) The highly crosslinked plasma polymer surface modification layer is non-volatile and insoluble, reducing the likelihood of outgassing and process contamination.

  (3) The surface modified layer is easily removed in oxygen plasma or downstream oxygen plasma at high temperature.

  (4) Since the surface modified layer is thin and easily removed, the glass carrier can be reused.

  PEN and PET are among the commonly selected polymeric substrates obtained in roll form for electronic component manufacturing. Compared to most polymers, they are relatively chemically inert, have low water absorption, low swelling, and are temperature resistant. However, these properties are inferior to those of glass. For example, the maximum temperature of non-thermally stabilized PEN is 155 ° C, while the maximum temperature of PET is only 120 ° C. These temperatures are low compared to operating temperatures of over 600 ° C. for display glass suitable for pSi processing. Thermal expansion is about 20 ppm for PEN compared to 3.5 ppm for display glass. And the temperature shrinkage is about 0.1% after 30 minutes at 150 ° C., which is far beyond the relaxation and compression in glass at significantly higher temperatures. These poor physical properties of polymer substrates require process adaptation to deposit high quality devices in high yields. For example, the deposition temperature of silicon dioxide, silicon nitride and amorphous silicon must be reduced to stay within the limits of a polymer substrate.

  The aforementioned physical properties of the polymer make it difficult to bond to rigid carriers for sheet-to-sheet processing. For example, the thermal expansion of a polymer sheet is typically more than six times that of display glass. Despite the lower upper temperature limit, the thermal stress is large enough to cause warpage and bowing and delamination when using conventional bonding techniques. Although the use of high expansion glass or higher expansion metal carriers such as soda lime helps to manage the warping challenge, these carriers typically include contamination, compatibility or roughness (thermal transfer). Issues).

The surface energy of PEN and PET is also significantly lower than that of glass. As shown in Table 16 below, "Corning""EagleXG" glass, after cleaning with SC1 chemistry and standard cleaning techniques, shows a surface energy of about 77mJ / m ^2. See Example 16e. Without surface treatment, PEN and PET have a surface energy of 43-45 mJ / m ² (43-45 dynes) and are non-polar. Table 2 from “Remote Atmospheric-Pressure Plasma Activation of the Surfaces of Polyethylene Terephthalate and Polyethylene Naphthalate” by E. Gonzalez, II, MD Barankin, PC Guschl, and RF Hicks, Langmuir 2008 24 (21), 12636-12643 See Table 15 below. Plasma cleaning process (e.g., by oxygen plasma), by increasing the polar component, the surface energy 55~65mJ / m ² (55~65 dyne, "plasma") to increase significantly. Also, UV ozone treatment or corona discharge may be used to clean the polymer and temporarily increase its surface energy. However, over time, the surface energy decreases and returns to its previous value ("aging").

These surface energies (about 55 to about 65 mJ / m ² ) for the binding surface of the polymer, and about 77 mJ / m ² for the binding surface of the glass carrier allow the polymer sheet to process structures on the sheet. The polymer could not be detached from the glass carrier when it was first fixed on the glass carrier and then heated to a moderate temperature, although it would not stick to the glass carrier enough to do so. Therefore, it has been found that it is beneficial to have the surface energy of the glass carrier approximately match the surface energy of PEN or PET in order to initially bind PEN or PET to the glass at room temperature. In addition, various of the above-described surface modification layers are capable of maintaining the polymer layer even after an organic-TFT processing cycle (including a 1 hour vacuum anneal at 120 ° C. and a 1 minute post-baking step at 150 ° C.). It has been found that the binding energy is controlled so that can be separated from the glass carrier.

By selecting an appropriate surface modification layer to properly adjust the surface energy of the glass carrier, a polymer, such as PEN or PET, can be applied to the glass carrier by organic-TFT processing (1 hour vacuum at 120 ° C.). (Including annealing and a 1 minute post-baking step at 150 ° C.) to achieve adequate wetting and adhesive strength to allow removal of the polymer from the carrier after processing, while controllably bonding in a suitable manner. it can. The polymer sheet can be successfully removed from the carrier, i.e., the polymer sheet remains between the OTFT on the polymer sheet and the OTFT on the mask used to make it, even after the above treatment. The polymer sheet is controllably bonded to the carrier if no noticeable difference in transistor arrangement is found. The surface modification layer may be selected from a variety of materials and treatments exemplified throughout the specification. The polymeric material may conveniently be plasma cleaned (to increase the polar component of surface energy to promote initial bonding) prior to bonding, but the current polymer (ie, as received, This is not necessary, as the surface energy of the glass carrier can be varied significantly to achieve a suitable level for controlled bonding with a washed or aged condition). Based on the examples described above and the examples in Table 16 below, achieving a surface energy in the range of about 36 mJ / m ² (Example 5g) to about 80 mJ / m ² (Example 5f) on the bonding surface of the glass carrier. Can be.

Some of the surface modification methods described above, including those formed from plasma polymerization of a carbon source, eg, a hydrocarbon gas, are suitable for bonding polymer sheets to glass supports. For example, plasma polymer films (Examples 5a and 5g) deposited from fluorocarbon gas; plasma polymer films (Example 5m) deposited from fluorocarbon gas and subsequently treated with nitrogen and hydrogen simultaneously; Plasma polymer films deposited from non-fluorine containing gases (Examples 6a-6j); Plasma polymer films deposited from various mixtures of hydrocarbons, optional nitrogen gas, and hydrogen gas (Examples 7a-g) 12j); plasma polymer films (Examples 9a-9j) deposited from various non-fluorine-containing gases and then treated with nitrogen, wherein their surface energies vary with cleanliness and / or aging. And deposited from a variety of non-fluorine-containing gases, and subsequently treated sequentially with nitrogen and then hydrogen (Examples 10a-10p); Others were treated by dilution of ammonia (eg 8b, 8d), or after, N ₂ -O _2, and then is by N ₂ (example 11a, 11e), or treated with N ₂ -O ₂ (Example 11f , 12c) plasma polymer membranes, all of which will work particularly well for plasma cleaning PEN. For polymers other than PET or PEN, other surface treatments may be appropriate, depending on the degree of washing and aging, depending on the surface energy of the polymer present just prior to binding. Would. After the surface energy of the glass carrier, which almost corresponds to the surface energy of the polymer sheet, after processing of the organic-TFT type (including a vacuum annealing at 120 ° C. for 1 hour and a post-baking step at 150 ° C. for 1 minute), It has been found to work well in both initial bonding and bonding control so that can be easily stripped.

  In addition, other formulations of the surface modified layer are studied to achieve a surface energy within the above range of the surface energy of the polymer sheet and bond the thin sheet of polymer to the glass carrier as follows: did.

One example of using a plasma polymerized membrane to adjust the surface energy of a surface modified layer bonding surface formed from a mixture of gases , cover it with surface hydroxyls, and / or control the type of polar bonds thereon. , Deposition of a thin film of a surface modified layer from a mixture of feed gases containing a hydrocarbon (eg, methane). The deposition of the surface modification layer may be performed at atmospheric or reduced pressure, and may include plasma excitation, such as DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF. It is performed by plasma. The plasma polymerized surface modification layer may be deposited on the bonding surface of the carrier, the thin sheet, or both. As mentioned earlier for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Control of reaction conditions and feed gas can be used to control the chemistry for tailoring the thickness, density, and functionality of the surface modified layer to the desired application. By controlling the properties of the membrane, including the amount of surface hydroxyls to be coated, the surface energy of the binding surface of the support can be adjusted. The surface energy controls the degree of bonding between the thin sheet and the carrier during subsequent processing performed to deposit a film or structure on the thin sheet, i.e., prevents permanent covalent bonding So that it can be adjusted.

In the examples in Table 16 below, various conditions were used to deposit a plasma polymerized film on a glass carrier. The glass carrier was a substrate manufactured from "Corning""EagleXG" (available from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to film deposition, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques. The film was deposited in a STS Multiplex PECVD apparatus in triode electrode placement mode (obtained from SPTS, Newport, UK), where the carrier was placed on a platen and 50 W of 380 kHz RF energy was applied to it. And a coil (showerhead) was placed on the platen, and 300 W of 13.5 MHz RF energy was applied thereto. The temperature of the platen was 200 ° C., and the gas flow rate through the showerhead was as shown in Table 16. (The flow rate is cubic centimeters per minute-sccm under standard conditions). Thus, for example, the notation in the column “Surface Modification Layer Deposition Process” of Table 16 for Example 16b reads as follows: In a STS Multiplex PECVD apparatus, at a platen temperature of 200 ° C. and a pressure of 300 millitorr. 200 sccm of H ₂ , 50 sccm of CH ₄ , and 50 sccm of C ₂ F ₆ were flowed together through the showerhead into the (about 40 Pa) bath; 300 W of 13.5 MHz RF energy was applied to the showerhead. 50 W of 380 kHz RF energy was applied to the platen on which the carrier was placed; deposition time was 120 seconds. The column notation for surface treatment for the remaining examples can be read as well. The surface energy is determined by using the contact angle (CA) and the Wu model of three different test liquids, in this case water (W), hexadecane (HD), and diiodomethane (DIM), and mJ / m ² (square meter). Per millijoule). For the surface energies, the polarity (P) and dispersion (D) components and the total (T) are shown. For these examples, the thickness “Th (A)” of the surface modification layer in Angstroms is also shown.

Example 16a is a bare "Eagle XG" glass after being cleaned by SC1 chemistry and standard cleaning techniques. Example 16e shows that after cleaning, the glass had a surface energy of about 77 mJ / m ² .

  Examples 16a to 16d show that a surface modifying layer is deposited on a glass surface to change its surface energy, and thus the surface of the glass is tailored to a particular bonding application. The example in Table 16 is an example of a one-step process, such as the examples in Tables 6 and 7, for depositing a surface modified layer having the desired surface energy and polar groups.

Example 16a shows that the surface modification layer may be a plasma polymerized film deposited from a mixture of hydrogen and methane (hydrocarbon) gas. In these examples, the surface modification layer was deposited on the cleaned glass carrier. Thus, deposition of a surface modifying layer has been shown to reduce surface energy from about 77 to about 49 mJ / m ^2, which is within the range of surface energies on the binding surface of a typical polymer. I have.

Example 16b shows that the surface modification layer may be a plasma polymerized film deposited from a mixture of hydrogen, methane (hydrocarbon), and a fluorine-containing gas (eg, C ₂ F ₆ , fluorocarbon). . In these examples, the surface modification layer was deposited on the cleaned glass carrier. Thus, deposition of a surface modifying layer has been shown to reduce the surface energy from about 77 to about 37 mJ / m ² (approximately within the surface energy on the binding surface of a typical polymer). . The surface energy achieved in Example 16b is lower than that achieved in Example 16a, and the addition of fluorine to the deposition gas reduces the surface energy otherwise achieved by similar surface modification layer deposition conditions. It is shown that it is possible.

Example 16c shows that the surface modification layer may be a plasma polymerized film deposited from a mixture of hydrogen, methane (hydrocarbon), and a nitrogen-containing gas (eg, N ₂ ). In this example, the surface modification layer was deposited on a cleaned glass carrier. Thus, the deposition of the surface modifying layer can increase the surface energy from about 77 to about 61 mJ / m ² (this is typical for O ₂ plasma treated polymer binding surfaces, such as during polymer sheet cleaning). Surface energy (within the range of surface energies). This surface energy is also in the compatible range for bonding the thin glass sheet to the carrier.

Example 16d shows that the surface modification layer may be a plasma polymerized film deposited from a mixture of methane (hydrocarbon), and a nitrogen-containing gas (eg, NH ₃ ). In this example, the surface modification layer was deposited on a cleaned glass carrier. Thus, the deposition of a surface modifying layer reduces the surface energy from about 77 to about 57 mJ / m ^2, which, again, is in the range of surface energies on a typical polymer binding surface. It is shown. Also, for some applications, this would be suitable for bonding the carrier to a thin glass sheet.

The surface energy achieved according to Examples 16c and 16d, as compared to the surface energy achieved according to Example 16a, is similar to the addition of nitrogen (by either N ₂ or NH ₃ ) to the deposition gas. Shows that the surface energy attained by can be increased.

The surface energy obtained with the surface modified layer of Example 16b was less than 50 mJ / m ² (considered to be suitable for controlling and bonding thin sheets of glass to a glass carrier). However, the surface modification layer is suitable for bonding a polymer binding surface to a glass binding surface. In addition, the surface modified layers of Examples 16c and 16d (formed from plasma polymerization of hydrocarbons (methane), optional hydrogen containing gas (H ₂ ), and nitrogen containing gas (N ₂ or ammonia)) It should be noted that the surface energy generated by the above may be greater than about 50 mJ / m ² and may therefore be adapted in some cases to bond a thin glass sheet to a glass carrier.

  The thin sheets bonded to the carrier with the surface modified layer deposited thereon as in Examples 16a to 16d of Table 16 were manufactured from TEONEX® Q65 PEN (obtained from DuPont) and 200 micrometers The substrate had a thickness of

  As in the example in Table 16, the bonding surface on which the surface modification layer was disposed was glass, but need not be. Alternatively, the bonding surface may be another suitable material having similar surface energies and properties as glass, for example, silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

The plasma polymerized hydrocarbon polymer membrane is doped with optional fluorocarbon (Example 16b), optional nitrogen (Example 16c), or optional ammonia (Example 16d) in STS Multiplex CVD in triode mode. May be deposited from methane and hydrogen (Example 16a). With the addition of fluorocarbon or nitrogen, surface energies as low as 37 mJ / m ² (Example 16b) and higher surface energies (about 61 mJ / m ² , Example 16c) can be achieved. Surface energies between the levels of Examples 16b and 16c (i.e., about 49 mJ / m < ² > in Example 16a, and about 57 mJ / m < ² > in Example 16d) can also be achieved, and therefore based on the deposition conditions including the deposition gas. Thus, the ability to adjust the surface energy of the surface modified layer is shown.

  As a counter-example, a polymer film was deposited on a SC1-cleaned bare glass carrier (Example 16e). However, the polymer sheet did not adhere sufficiently to the carrier to allow processing of the structure on the polymer sheet.

  In order to be suitable for the organic-TFT processing, it is required to have a wet strength and a bonding strength or more. The very different thermal expansion between the polymer membrane and the carrier is best managed by choosing a high expansion glass to minimize the differential expansion and by reducing the speed of the heating and cooling steps. You. The need for a smooth and clean substrate surface with minimal water absorption during processing will be achieved by spinning and curing a suitable thin layer of organic dielectric. Both flatten the surface and form a barrier for moisture and other contaminants.

PEN (200 micron thick sheet of "TEONEX" Q65 from DuPont) was bonded to a "Corning""EagleXG" glass carrier using a surface modification layer process. Very good bonding performance was seen for the amorphous carbon layer deposited under the following conditions: 50 sccm CH ₄ , 200 sccm H ₂ , 300 W 13.56 MHz RF energy at 300 W, platen at 200 ° C. 50 W, 380 kHz RF energy and 2 minute deposition time. Prior to bonding, PEN was exposed to a UV-ozone cleaner for 5 minutes. This has been found to improve the adhesion. PEN was applied using a Teflon squeegee. An alicyclic epoxy layer about 150 nm thick was spun on PEN and cured to flatten surface defects. The organic gate insulator (OGI) was a photopatternable cycloaliphatic epoxy.

An array of bottom gate type bottom contact type organic thin film transistors was formed by the following process. A 100 nm Al gate metal was deposited by sputtering in AJA, lithographically patterned with Fuji 6512 resist, and patterned on the gate by wet etching in an A-type Al etchant. The photoresist was removed in a PGMEA bath at room temperature for 3 minutes, followed by rinsing with IPA / DI (the NMP-based stripper was incompatible with the epoxy layer). A second epoxy gate insulator layer was spun on the patterned gate and cured. A 100 nm thick Ag S / D metal was sputtered, lithographically patterned with Fuji 6512 and etched with a 1: 1 mixture of Transene TFS: pH 10 buffer. Although the etching rate of Ag was high, the dissolution of the etching product was slow, so that etching was difficult. Very good results were obtained by etching for 5 seconds, removing the etching products by spraying with deionized water, and repeating 4 to 5 times. Wetting of the tetrathienoacene-DPP copolymer (PTDPPTFT4) organic semiconductor (OSC) layer was difficult. OSC adhesion was promoted by HMDS treatment in a YES oven at 120 ° C. The OSC polymer was dissolved in 6 parts decalin: 4 parts toluene at a concentration of 5 mg / mL. OSCs were applied by spinning in a Laurel spinner with manual dispensing, 20 seconds rest, 500 rpm for 30 seconds, 1000 rpm for 60 seconds. The OSC film was soft baked on a hot plate at 90 ° C. for 2 minutes and vacuum annealed at 120 ° C. for 1 hour in a Salvis oven under low vacuum to remove residual decalin. A third OGI layer was spun onto OSC using a brief 5 second O ₂ plasma in Branson to improve adhesion, 2.5 second exposure, 1 minute pause, and 1 minute The light pattern was directly formed by post-baking at 150 ° C. After a one minute pause, the active pattern was tray developed in PGMEA for one minute, followed by an IPA and DI rinse. An active pattern is formed using dry etching in Unaxis 790 RIE using 30 sccm O ₂ , 10 sccm Ar, 20 sccm CHF ₃ , 50 mTorr (about 6.7 Pa), 200 W for 15 seconds. , Exposing the gate metal. The performance of the 75/75 μm TFTs is summarized in the table shown in FIG. This table shows typical 75-micrometer channel width and 75-micrometer channel length, bottom-gate, bottom-contact organic thin-film transistors fabricated on PEN controllably bonded to the glass carrier described above. 4 shows drain current versus gate current and performance for a transistor. The PEN was easily peeled off by forming a crack using a razor blade and then peeling off. Since no significant differences in transistor placement between the OTFT on the polymer sheet and the OTFT on the mask used to make it were seen, the polymer sheet was even Successfully removed from the carrier.

  The above-described process for forming an array of bottom-gate, bottom-contact organic thin-film transistors may be performed using a suitable surface modification layer selected from those described herein with the aid of “Corning” Gorilla® Glass (Corning, NY). A PEN sheet (200 micron thick sheet of “TEONEX” Q65 from DuPont) controllably bonded to a carrier made from alkali-containing chemically strengthenable cover glass obtained from Corning Incorporated, Inc. I did well.

  As mentioned above, the polymer itself may be a substrate on which other devices can be manufactured. Alternatively, the polymer may be a polymer substrate on a composite substrate, for example, a glass / polymer composite. In this case, the polymer surface of the glass / polymer composite will face the carrier and will be bound thereto as described above. On the other hand, the glass surface of the glass / polymer composite will be exposed as a surface on which electrons or other structures can be manufactured. After producing the electrons or other structures on the glass surface of the glass / polymer composite, the polymer surface of the composite may be stripped from the surface modified layer on the carrier. In this embodiment, the glass layer in the glass / polymer composite is particularly thin, for example, having a thickness of 50 micrometers or less, 40 micrometers or less, 30 micrometers or less, 20 micrometers or less, 10 micrometers or less, or It may be advantageous when it is less than 5 micrometers. In such cases, the polymer portion of the glass / polymer composite not only serves as a binding surface for attaching the composite to the carrier, but also provides some composites when the composite is not on the carrier. Will provide handling advantages.

Conclusion It is emphasized that the above-described embodiments of the present invention, and in particular any "preferred" embodiments, are merely possible examples of implementation and merely set forth a clear understanding of the various principles of the present invention. Should be. Many changes and modifications may be made to the above-described embodiments of the invention without departing substantially from the spirit and various principles of the invention. All such modifications and changes are intended to be included within the scope of the present disclosure and the present invention and protected by the following claims.

  For example, although the surface modification layer 30 of many embodiments has been shown and discussed as being formed on the carrier 10, it may alternatively or additionally be formed on the thin sheet 20. . That is, if necessary, the material as described in the examples of Tables 3 to 12 and 16 is applied to the carrier 10, the thin sheet 20, or both the carrier 10 and the thin sheet 20 on the surfaces to be joined together. Is also good.

  Furthermore, it has been stated that some surface modification layers 30 control the bond strength so that the thin sheet 20 can be removed from the carrier 10 even after processing the article 2 at a temperature of 400 ° C. or 600 ° C. Process the article 2 at a temperature lower than the temperature of the particular test that the article passed, and still achieve the same ability to remove the thin sheet 20 from the carrier 10 without damaging either the thin sheet 20 or the carrier 10 It is also possible.

  Furthermore, while the concept of controlled bonding has been described herein as being used for carriers and thin sheets, in certain circumstances these concepts may cause the sheets (or portions thereof) to separate from one another. Can also be applied to control the bonding between thicker sheets of glass, ceramic, or glass-ceramic, which may be desirable.

  Still further, while the concept of controlled bonding herein has been described as being useful for glass supports and thin sheets of glass, the supports may be made from other materials, such as ceramics, glass ceramics, or metals. You may. Similarly, the sheet controllably bonded to the carrier may be made from other materials, for example, ceramic or glass ceramic.

  Furthermore, while the surface modified layers of Examples 3 and 3-12 above were described as being formed by plasma polymerization, other techniques, such as thermal evaporation, sputtering, UV of gas species that reacts with the bonding surface, Activation or even wet chemistry may be possible.

Furthermore, although the carbonaceous surface modified layers formed by plasma polymerization of Examples 6-12 were formed using methane as the polymer forming gas, other carbon-containing feeds may be possible. For example, carbon-containing sources include: 1) hydrocarbons (alkanes, alkenes, alkynes or aromatics; alkanes include, but are not limited to, methane, ethane, propane, and butane; Alkynes include, but are not limited to, acetylene, methylacetylene, ethylacetylene, and dimethylacetylene; alkynes include, but are not limited to, Benzene, toluene, xylene, ethylbenzene); 2) alcohols (including methanol, ethanol, propanol); 3) aldehydes or ketones (including formaldehyde, acetaldehyde and acetone); 4) amines (methylamine, dimethyl). Amine, Including trimethylamine and ethylamine); including 6) nitrile (acetonitrile); 5) organic acids (formic acid and acetic acid) 7) CO; and 8) CO _2: may include at least one of. Alternatively, the carbon-containing source may include one or more of the following: 1) saturated or unsaturated hydrocarbon, or 2) a nitrogen-containing or 3) an oxygen-containing saturated or unsaturated hydrocarbon or 4,) CO or CO _2. Exemplary carbon-containing feed material into some general, carbon-containing gas, such as methane, ethane, propane, butane, ethylene, propylene, propyne, acetylene, MAPP, CO and CO ₂ and the like.

  Furthermore, the surface modification layer was used to treat and thereby increase the surface energy as in the examples of Examples 5 and 8-12, or the surface modification layer as in Examples 7, 16c, 16d While the polar groups used to form themselves were nitrogen and oxygen, other polar groups, such as sulfur and / or phosphorus, may also be possible.

Moreover, while N ₂ and NH ₃ were used as the nitrogen-containing gas, other nitrogen-containing materials, for example, hydrazine, N ₂ O, NO, N ₂ O _4, methylamine, dimethylamine, trimethylamine and ethylamine, acetonitrile Is sometimes used.

Further, the oxygen-containing gas used was N ₂ -O ₂ and O _2, other oxygen-containing gas, for example, O _3, H ₂ O, methanol, ethanol, propanol, N ₂ O, NO, and N _It may be possible to use ₂ O ₄ .

  As can be seen from the examples discussed herein, the surface modified layers, including those that have been subsequently treated, can be from about 1 nm (Example 16b) or 2 nm (Examples 3, 4) to about 10 nm (Example 12c, 8.8 nm). Thickness can be achieved. In addition, thicker surface modification layers are possible, as described with respect to FIG. However, as the thickness exceeds about 70 nm, the surface modification layer begins to become opaque, which may not be desirable for applications that benefit from optical clarity.

  The various above-mentioned concepts according to the present application may be combined with one another in any and all different combinations of manners. As an example, various concepts may be combined according to the following aspects.

According to a first aspect, there is provided a method for controllably coupling a substrate to a carrier, comprising:
Obtaining a substrate having a polymer binding surface having a first surface energy;
Obtaining a carrier having a glass binding surface with a second surface energy,
Depositing a surface modifying layer on the glass binding surface so as to reduce the surface energy of the glass binding surface, and binding the polymer binding surface to the glass binding surface via the surface modifying layer, Wherein the substrate is non-destructively peelable from the carrier after being subjected to a 1 hour vacuum anneal in an environment having a temperature of 120 ° C.,
Is provided.

According to a second aspect, the surface-modified layer comprises:
Plasma polymerization of carbon-containing gas,
Plasma polymerization of hydrocarbon-containing gas,
Plasma polymerization of hydrocarbon-containing and fluorocarbon-containing gases,
Plasma polymerization of hydrocarbon-containing and hydrogen-containing gases,
Plasma polymerization of a hydrocarbon-containing gas to form a layer, after which the layer is treated with a nitrogen-containing gas, plasma polymerization,
Plasma polymerization of a hydrocarbon-containing gas to form a layer, followed by continuous treatment of the layer with two other gases, one containing nitrogen and the other containing hydrogen. Plasma polymerization,
Plasma polymerization of a hydrocarbon-containing gas to form a layer, followed by continuous treatment of the layer with two other gases, one containing nitrogen and oxygen and the other containing nitrogen. Is performed, plasma polymerization,
Plasma polymerization of a hydrocarbon-containing gas to form a layer, followed by treatment of the layer with a nitrogen and oxygen-containing gas, plasma polymerization,
Plasma polymerization of hydrocarbon containing, nitrogen containing, and hydrogen containing gases,
Plasma polymerization of hydrocarbon-containing and hydrogen-containing gas to form a layer, after which the layer is treated with a nitrogen-containing gas, plasma polymerization,
Plasma polymerization of fluorocarbon-containing gas,
Plasma polymerization of a fluorocarbon-containing and hydrogen-containing gas, and plasma polymerization of a fluorocarbon-containing gas to form a layer, after which the layers are simultaneously treated with a nitrogen-containing and hydrogen-containing gas. ,
The method of aspect 1, wherein the method is deposited by one of the following:

  According to a third aspect, there is provided the method of aspect 1, wherein the surface modification layer is deposited by plasma polymerization of a gas of methane, ammonia, and hydrogen.

  According to a fourth aspect, there is provided the method of aspect 2, wherein said carbon-containing gas comprises at least one of a hydrocarbon, alkane, alkene, alkyne, or aromatic compound.

According to a fifth aspect, the carbon-containing gas, methane, ethane, propane, butane, ethylene, propylene, propyne, acetylene, CO, and CO containing ₂ of at least one method of embodiment 2 is provided .

According to a sixth aspect, when a hydrogen-containing gas is used, the hydrogen-containing gas includes H ₂ , and when a nitrogen-containing gas is used, the nitrogen-containing gas includes ammonia, N ₂ , hydrazine, N ₂ A method is provided for any one of aspects 2, 4, and 5, comprising at least one of ₂ O, NO, N ₂ O ₄ , methylamine, dimethylamine, trimethylamine, ethylamine, and acetonitrile.

According to a seventh aspect, when the hydrogen-containing gas is used, the hydrogen-containing gas comprises H _2, if the oxygen-containing gas is used, the oxygen-containing _{gas, O 2, O 3, H} 2 O, methanol, ethanol, propanol, N ₂ O, NO, and N ₂ O containing ₄ at least one, either one method aspect 2,4～6 is provided.

  According to an eighth aspect, there is provided the method of any one of aspects 1 to 7, wherein the thickness of the surface modified layer is 1 to 70 nm.

  According to a ninth aspect, there is provided the method of any one of aspects 1 to 7, wherein the thickness of the surface modified layer is 2 to 10 nm.

  According to a tenth aspect, there is provided the method of any one of aspects 1-9, further comprising the step of washing the polymer binding surface to provide a first surface energy.

  According to an eleventh aspect, there is provided the method of aspect 10, wherein the cleaning step comprises one of oxygen plasma cleaning, UV ozone treatment, and corona discharge.

  According to a twelfth aspect, there is provided the method of any one of aspects 1 to 11, wherein the substrate is a composite comprising a polymer and glass.

  According to a thirteenth aspect, there is provided the method of any one of aspects 1 to 12, wherein the glass binding surface has an average surface roughness Ra of 1 nm or less before deposition of the surface modification layer.

  According to a fourteenth aspect, there is provided the method of any one of aspects 1 to 13, wherein the thickness of the substrate is no greater than 300 micrometers.

  According to a fifteenth aspect, there is provided the method of any one of aspects 1-14, wherein the thickness of the carrier is between 200 micrometers and 3 mm.

According to a sixteenth aspect, an article,
A substrate having a polymer binding surface,
A carrier having a glass-binding surface, and a plasma-polymerized surface-modifying layer that releasably bonds the polymer-binding surface to the glass-binding surface;
An article comprising:

  According to a seventeenth aspect, there is provided the article of aspect 16, wherein the thickness of the surface modification layer is 1 to 70 nm.

  According to an eighteenth aspect, there is provided the article of aspect 16, wherein the thickness of the surface modification layer is 2 to 10 nm.

According to a nineteenth aspect, the surface-modified layer comprises:
Plasma polymerized hydrocarbons, and plasma polymerized fluorocarbons,
The article of any one of aspects 16-18, comprising at least one of the following:

  According to a twentieth aspect, there is provided the article of any one of aspects 16 to 19, wherein the substrate is a composite comprising a polymer and glass.

  According to a twenty-first aspect, the article of any one of aspects 16-20, wherein the glass binding surface has an average surface roughness Ra of 1 nm or less when no surface modification layer is disposed thereon. Is provided.

  According to a twenty-second aspect, in any one of aspects 16 to 20, wherein the glass binding surface has an average surface roughness Ra of 0.2 nm or less when no surface modification layer is disposed thereon. One article is provided.

  According to a twenty-third aspect, the article according to any one of aspects 16 to 22, wherein the thickness of the substrate is 300 micrometers or less.

  According to a twenty-fourth aspect, there is provided the article of any one of aspects 16-23, wherein the thickness of the carrier is from 200 micrometers to 3 mm.

According to Aspect A, in a glass article:
A carrier having a carrier binding surface;
8. a surface-modifying layer disposed on the carrier-binding surface, wherein the carrier-binding surface is bonded to the glass sheet-binding surface by a surface-modifying layer therebetween, within the vessel at 9. Subject the article to a temperature cycle where it is heated from room temperature to 600 ° C. at a rate of 2 ° C., held at a temperature of 600 ° C. for 10 minutes, and then cooled at 1 ° C. per minute to 300 ° C. After removing the article and allowing the article to cool to room temperature, if one is held and the other is exposed to gravity, the carrier and sheet will not separate from each other and there will be no outgassing from the surface modified layer during temperature cycling, The surface-modified layer, which is configured so that the thinner of the carrier and the sheet can be separated from the carrier without breaking into two or more pieces,
A glass article comprising:

According to Aspect B, in a glass article:
A carrier having a carrier binding surface;
A sheet having a sheet binding surface;
A surface modifying layer disposed on one of the carrier binding surface and the sheet binding surface;
With
The carrier binding surface is bound to the sheet binding surface by a surface modifying layer therebetween, and the surface energy binding the sheet to the carrier is increased from room temperature to 600 ° C. at a rate of 9.2 ° C. per minute in the bath. The article is subjected to a temperature cycle, which is heated to a temperature of 600 ° C. for 10 minutes, and then cooled at 1 ° C. per minute to 300 ° C., then the article is removed from the bath and the article is cooled to room temperature. After that, if one is held and the other is exposed to gravity, the carrier and the sheet do not separate from each other, there is no outgassing from the surface modified layer during temperature cycling, and the two thinner pieces of the carrier and the sheet Provided is a glass article having such characteristics that the sheet can be separated from the carrier without breaking.

  According to Aspect C, there is provided the glass article of any one of Aspects A or B, wherein the thickness of the surface modified layer is 0.1 to 100 nm.

  According to Aspect D, there is provided the glass article according to any one of Aspects A or B, wherein the thickness of the surface modified layer is 0.1 to 10 nm.

  According to Aspect E, there is provided the glass article according to any one of Aspects A or B, wherein the thickness of the surface-modified layer is 0.1 to 2 nm.

  According to any one of the aspects F, the carrier is a glass comprising alkali-free aluminosilicate or borosilicate or aluminoborosilicate, each having a level of not more than 0.05% by weight of arsenic and antimony. Certain glass articles of any one of Aspects A to E or 1 to 24 are provided.

  According to Aspect G, the glass article according to any one of Aspects A to F or 1 to 24, wherein each of the carrier and the sheet has a size of 100 mm × 100 mm or more.

  Hereinafter, preferred embodiments of the present invention will be described separately.

Embodiment 1
A method for controllably coupling a substrate to a carrier, comprising:
Obtaining a substrate having a polymer binding surface having a first surface energy;
Obtaining a carrier having a glass binding surface with a second surface energy,
Depositing a surface modifying layer on the glass binding surface so as to reduce the surface energy of the glass binding surface; and bonding the polymer binding surface to the glass binding surface via the surface modifying layer Wherein the substrate is non-destructively peelable from the carrier after being subjected to a vacuum anneal for 1 hour in an environment having a temperature of 120 ° C.
A method comprising:

Embodiment 2
The surface modified layer,
Plasma polymerization of carbon-containing gas,
Plasma polymerization of hydrocarbon-containing gas,
Plasma polymerization of hydrocarbon-containing and fluorocarbon-containing gases,
Plasma polymerization of hydrocarbon-containing and hydrogen-containing gases,
Plasma polymerization of a hydrocarbon-containing gas to form a layer, after which the layer is treated with a nitrogen-containing gas, plasma polymerization,
Plasma polymerization of a hydrocarbon-containing gas to form a layer, followed by continuous treatment of the layer with two other gases, one containing nitrogen and the other containing hydrogen. Performed, plasma polymerization,
Plasma polymerization of a hydrocarbon-containing gas to form a layer, after which the continuation of the layer with two other gases, one gas containing nitrogen and oxygen and the other gas containing nitrogen. Processing, plasma polymerization,
Plasma polymerization of a hydrocarbon-containing gas to form a layer, followed by treatment of said layer with a nitrogen and oxygen-containing gas, plasma polymerization,
Plasma polymerization of hydrocarbon containing, nitrogen containing, and hydrogen containing gases,
Plasma polymerization of a hydrocarbon-containing and hydrogen-containing gas to form a layer, after which said layer is treated with a nitrogen-containing gas, plasma polymerization,
Plasma polymerization of fluorocarbon-containing gas,
A plasma polymerization of a fluorocarbon-containing and hydrogen-containing gas, and a plasma polymerization of a fluorocarbon-containing gas to form a layer, after which the layer is simultaneously treated with a nitrogen-containing and hydrogen-containing gas. polymerization,
2. The method of embodiment 1, wherein the method is deposited by one of the following:

Embodiment 3
The method of embodiment 1, wherein the surface modification layer is deposited by plasma polymerization of a gas of methane, ammonia, and hydrogen.

Embodiment 4
The method of embodiment 1, wherein the thickness of the surface modification layer is 1 to 70 nm.

Embodiment 5
2. The method of embodiment 1, further comprising cleaning the polymer binding surface to provide the first surface energy.

Embodiment 6
The method of embodiment 1, wherein the substrate is a composite comprising a polymer and glass.

Embodiment 7
The method of embodiment 1, wherein the glass binding surface has an average surface roughness Ra of 1 nm or less prior to deposition of the surface modification layer.

Embodiment 8
The method of embodiment 1, wherein the thickness of the substrate is less than or equal to 300 micrometers.

Embodiment 9
An article,
A substrate having a polymer binding surface,
A carrier having a glass-binding surface, and a plasma-polymerized surface-modifying layer that releasably bonds the polymer-binding surface to the glass-binding surface.
Articles with.

Embodiment 10
The article of embodiment 9, wherein the surface modified layer has a thickness of 1 to 70 nm.

Embodiment 11
The surface modified layer,
Plasma polymerized hydrocarbons, and plasma polymerized fluorocarbons,
The article of embodiment 9, comprising at least one of the following.

Embodiment 12
The article of embodiment 9, wherein the substrate is a composite comprising a polymer and glass.

Embodiment 13
The article of embodiment 9, wherein the glass binding surface has an average surface roughness Ra of 1 nm or less when the surface modification layer is not disposed thereon.

Embodiment 14
The article of embodiment 9, wherein the substrate has a thickness of 300 micrometers or less.

2 Article 10, 900 Carrier 20 Thin sheet 30, 790 Surface modification layer 40 Bonding area 50 Controlled bonding area 760 Laminate 770-772 Glass sheet 780, 781 Cover sheet 910 Cover 920 Spacer 930 Heating tank

Claims (15)

A method for controllably bonding a substrate to a carrier to form an article,
Obtaining a glass substrate having a substrate bonding surface having a first surface energy;
Obtaining a glass carrier having a carrier binding surface with a second surface energy,
Depositing a surface modifying layer on the carrier binding surface to reduce the surface energy of the carrier binding surface, wherein the surface modifying layer is a plasma polymerization of a mixture comprising an etching gas and a fluoropolymer forming gas. Wherein the fluoropolymer forming gas comprises less than 40% of the mixture, and wherein the substrate-bonded surface via the surface-modifying layer is supported by the carrier. Binding to a binding surface, wherein the surface-modifying layer is 9.2 minutes per minute in the bath when the carrier-binding surface is bound to the substrate-binding surface by the surface-modifying layer therebetween. A temperature plate that is heated from room temperature to 600 ° C. at a rate of 10 ° C., held at a temperature of 600 ° C. for 10 minutes, and then cooled at 1 ° C. per minute to 300 ° C. After applying the article to a vessel and removing the article from the bath and allowing the article to cool to room temperature, the glass carrier and the glass substrate are separated from each other when one is held and the other is exposed to gravity. No gas is released from the surface modified layer during the temperature cycle, and the glass substrate and the glass substrate can be separated from the glass carrier without breaking the thinner one of the two or more pieces. A method comprising the steps of: The method according to claim 1, wherein the etching gas contained in the mixture is CF ₄ . The method of claim 1, wherein the fluoropolymer-forming gas contained in the mixture is selected from at least one of CHF ₃ , C ₃ F ₆ , and C ₄ F ₈ . The method of claim 1, wherein the etching gas included in the mixture includes CF ₄ , and the fluoropolymer forming gas included in the mixture includes C ₄ F ₈ . C ₄ F ₈ is less than 30% of said mixture The method of claim 4, wherein. 5. The method of claim ₄ , wherein CF4 is greater than 50% of the mixture. It said mixture further comprises H _2, The method of claim 4. The method of claim 1, wherein the etching gas included in the mixture includes CF ₄ and the fluoropolymer forming gas included in the mixture includes CHF ₃ . CHF ₃ is less than 30% of said mixture The method of claim 8. CF ₄ is more than 50% of said mixture The method of claim 8.   The method of claim 1, wherein the surface modification layer has a thickness in a range from 1 nm to 10 nm.   The method of claim 1, wherein the surface modification layer has a thickness in a range from 0.1 nm to 2 nm. The method of claim 1, wherein the surface modified layer deposited has a surface energy greater than 40 mJ / m ² .   The method of claim 1, wherein the glass carrier has a thickness of 200 μm to 3 mm, and the glass substrate has a thickness of 300 μm or less.   The method of claim 1, further comprising cleaning the substrate bonding surface to provide the first surface energy.