JP2017511756A - Treatment of surface modified layers for controlled bonding of thin sheet carriers. - Google Patents

Abstract

A method for controllably bonding a thin sheet having a thin sheet binding surface to a carrier having a carrier binding surface. A surface modification layer is deposited on at least one of the thin sheet binding surface and the carrier binding surface so as to obtain a first surface energy on one of the thin sheet binding surface and the carrier binding surface. The surface modification layer is treated to change the first surface energy to a second surface energy that is greater than the first surface energy. Then, the thin sheet bonding surface is bonded to the carrier bonding surface via the surface modification layer. The deposition of the surface modification layer and its treatment may be performed by a plasma polymerization process.

Description

priority

  This application claims the benefit of priority of US Provisional Patent Application No. 61/931912, filed January 27, 2014, the contents of which are relied upon and incorporated herein in full.

  The present invention relates to articles and methods for treating soft sheets on a carrier, and more particularly to articles and methods for treating soft glass sheets on a glass carrier.

  Flexible substrates offer the promise of cheaper devices using roll-to-roll processing and the potential to produce thinner, lighter, more flexible and durable displays. However, the technology, equipment and processes required for roll-to-roll processing of high quality displays have also not been fully developed. Panel manufacturers have already invested heavily in machine tools for processing large glass sheets, so it is thinner to manufacture display devices by laminating flexible substrates on carriers using the sheet-to-sheet processing method. Presents 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 manufacturing was a sheet-to-sheet where the PEN was laminated to a glass carrier. The upper temperature limit of PEN limits the device quality and the processes that can be used. Moreover, the high permeability of the polymer substrate results in environmental degradation of OLED devices that require nearly hermetic packaging. Although thin film encapsulation offers the prospect of overcoming this limitation, it has not yet been demonstrated to present large and acceptable yields.

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

  However, flat panel display (FPD) processes, which are heat, vacuum, solvent and acid, and ultrasonic, require a strong bond 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 process (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. Including), acid etching (metal etching, oxide semiconductor etching), solvent exposure (photoresist removal, polymer encapsulant deposition), and ultrasonic exposure (photoresist solvent removal and typically in alkaline solution) Washing with water).

  Bonded wafer bonding is widely used in semiconductor processing for back-end processes where microelectromechanical systems (MEMS) and processes are less demanding. Commercial adhesives by Brewer Science and Henkel are typically thick polymeric adhesive layers that are 5 to 200 micrometers thick. The large thickness of these layers creates the potential for large amounts of volatile materials, 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 a sink for gases, solvents and acids (which can be degassed in subsequent processes).

  In Patent Document 1 filed on Feb. 8, 2012, entitled Processing Flexible Glass with a Carrier, the concept is that a thin sheet, for example, a soft glass sheet, is first bonded to a carrier by van der Waals force, Then, while maintaining the ability to remove portions of the thin sheet after processing the thin sheet / carrier, the bond strength in a particular area is increased and the device (e.g. electronic or display device, electronic or display device) It is disclosed to include each step of 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 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 combined seal portion between the thin sheet and the carrier is hermetic, and in some preferred embodiments, the seal wraps around the outside of the article, thereby from any region of the sealed article. Alternatively, liquid or gas can be prevented from entering any region.

  U.S. Pat. No. 6,057,089 then describes low temperature polysilicon (LTPS) (which is at a lower temperature compared to solid phase crystallization processes that can be up to about 750 ° C.) device manufacturing process, temperatures reaching 600 ° C. or higher, vacuum, and It discloses that a wet etch environment may be used. These conditions limit the materials that may be used and place high demands on the carrier / thin sheet. Therefore, it would be desirable to utilize the manufacturer's existing capital infrastructure, without loss of bond strength between the thin glass and the support at higher processing temperatures, or without contamination, and thin glass, i.e., thickness Is a carrier approach that allows processing of glass of 0.3 mm or less, and that the thin glass is easily peeled from the carrier at the end of the process.

  One commercial advantage over the approach disclosed in US Pat. No. 6,087,089 is that, as mentioned in US Pat. No. 5,047,086, manufacturers can, for example, PV, OLED, LCD, and patterned thin film transistor (TFT) electronics. It is possible to utilize existing capital investments in processing equipment while gaining the advantages of thin glass sheets. Moreover, by that approach: to facilitate bonding: flexibility for cleaning and surface treatment of thin glass sheets and carriers; flexibility for strengthening bonding between thin sheets and carriers in the bonding area; Flexibility for maintaining the peelability of the thin sheet from the carrier in the area (or reduced / low strength bonding); and flexibility for cutting the thin sheet to facilitate removal from the carrier. It becomes possible.

In the glass-to-glass bonding process, the glass surface is washed to remove all metal, organic and particulate residues, leaving most of the silanol terminated surface. The glass surfaces are first brought into intimate contact, where they are attracted together by van der Waals and / or hydrogen bonding forces. With heat and optional pressure, the silanol groups on the surface condense to form strong Si-O-Si covalent bonds across the interface, permanently bonding the glass pieces. Metal, organic and particulate residues obstruct bonding by masking the surface and preventing the intimate contact necessary for bonding. Since the number of bonds per unit area is determined by the probability that two silanol species on the opposing surfaces react and dehydrate and condense, a high silanol surface concentration is also required to form strong bonds. Zhuravrel reported that for fully hydrated silica, the average number of hydroxyls per nm ² was 4.6 to 4.9 (Non-Patent Document 1). In U.S. Pat. No. 6,057,831, unbonded regions are formed within the bonded perimeter, and the primary mode described for forming such unbonded areas is to increase surface roughness. An average surface roughness of Ra greater than 2 nm can prevent glass-to-glass bonds from forming during the high temperatures of the bonding process. Controlling van der Waals and / or hydrogen bonding between a support and a thin glass sheet in US Pat. No. 5,637,028, filed Dec. 13, 2012 by the same inventor entitled “Facilitated Processing for Controlling Bonding Between Sheet and Carrier” By doing so, a controlled coupling area is formed, but a covalent coupling area is still used as well. Thus, the articles and methods for processing thin sheets with a carrier in US Pat. Nos. 5,047,036 and 2,200 can withstand the harsh environment of FPD processing methods, but are undesirable for some applications. A strong covalent bond between a thin glass and a glass support in a bonding region that is covalently bonded, for example, Si—O—Si covalently bonded, with an adhesive strength of about 1000 to 2000 mJ / m ² , comparable to the strength. Is prevented from being reused. Prying or peeling cannot be used to separate the covalently bonded portion 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 on top is scored and removed, leaving a thin glass sheet bonded periphery on the carrier.

US Provisional Patent Application No. 61/596727 US Provisional Patent Application No. 61/768880

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 (no gas generation that would be incompatible with the semiconductor or display manufacturing process in which it is used), and to process another thin sheet There is a need for a thin sheet and carrier article that allows the entire area of the thin sheet to be removed from the carrier (either all at once or one area at a time) so that the carrier can be reused.

  This specification is powerful enough to withstand FPD processing (including LTPS processing), but to form a temporary bond that is weak enough to release the sheet from the support even after high temperature processing. A method for controlling adhesion between thin sheets is described. Such controlled bonding can be utilized to form an article with a reusable carrier, or an article with a controlled bond and covalent bond pattern area between the carrier and the sheet. More particularly, the present disclosure provides for thin sheet, support, or both to control both room temperature van der Waals and / or hydrogen bonding and high temperature covalent bonding between the thin sheet and the support. A surface modification layer (including various materials and associated surface heat treatments) is provided. Even more particularly, room temperature bonding may be controlled to be sufficient to hold the thin sheet and carrier together during vacuum processing, wet processing, and / or ultrasonic cleaning processing. At the same time, high temperature covalent bonding may be controlled to prevent permanent bonding between the thin sheet and the carrier during high temperature processing, as well as maintain sufficient bonding to prevent delamination during high temperature processing. In an alternative embodiment, the surface modification layer may provide a further processing option, for example, between the carrier and the sheet, even after cutting the article into smaller pieces for additional device processing. In order to maintain the air tightness of the various bonded bonding areas (carriers and sheets are sufficient throughout various processes including vacuum processing, wet processing, and / or ultrasonic cleaning processing) To remain attached). Furthermore, certain surface modification layers provide control of the bond between the support and the sheet, while at the same time being subject to extreme conditions in FPD (eg, LTPS) processing environments, including high temperature and / or vacuum processing, for example. Reduce gas emissions inside. Furthermore, in an alternative embodiment, several surface modification layers may be used on a support having a glass binding surface to controllably bond a thin sheet having a polymer binding surface. The polymer binding surface may be part of a thin sheet of polymer on which electrons or other structures are formed, or the polymer binding surface is formed on which electrons or other structures are formed. 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 vary as illustrated in the described description and accompanying drawings. It will be appreciated by implementing certain aspects. The foregoing general description and the following detailed description are merely exemplary of various aspects, and may provide an overview or skeleton 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 the principles and operation of the invention by way of example. It should be understood that the various features disclosed in this specification and the drawings can be used in any combination and in all combinations. By way of non-limiting example, various features may be combined with each other as set forth in the appended claims.

Schematic side view of an article having a carrier bonded to a sheet thinner than the surface modification 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 one proportion of the component materials that produced the film Schematic plan view of a thin sheet bonded to a carrier by a bonding area Schematic side view of glass sheet laminate 7 is an exploded view of one embodiment of the laminate of FIG. Schematic diagram of test arrangement A group of graphs of surface energy against time for different materials under different conditions (of different parts of the test arrangement of FIG. 9) Graph of change in bubble area% with respect to temperature for various materials Another graph of change in bubble area% over temperature for various materials Graph of the surface energy of a fluoropolymer film deposited on a glass sheet as a function of one proportion of the gas used during deposition Graph of the surface energy of a fluoropolymer film deposited on a glass sheet as a function of one proportion of the gas used during deposition Graph of surface energy versus deposition time for surface modified layers Graph of thickness versus logarithmic / log scale deposition time for surface modified layers Graph of surface energy versus processing temperature for different surface modification layers Graph of surface coverage of surface modified layer Summary of the performance of organic transistors fabricated on 200 micrometer PEN films bonded to glass carriers

  In the following detailed description, for purposes of explanation and not limitation, example embodiments disclosing specific details are set forth in order to provide a thorough understanding of the various principles of the invention. However, it will be apparent to those skilled in the art having the benefit of this disclosure that the present invention may be practiced in other embodiments that depart from the specific details disclosed therein. Further, descriptions of known devices, methods and materials may be omitted so as not to obscure the description of various principles of the invention. Finally, wherever applicable, like reference numerals refer to like elements.

  Ranges can be expressed herein as “about” from 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, using the antecedent “about,” it will be understood that the particular value forms another embodiment. It will be further understood that each endpoint of the range is significant both with respect to the other endpoint and regardless of the other endpoint.

  Directional terms used herein, for example, top, bottom, right, left, front, back, top, bottom, are used only with respect to the drawings drawn and are not intended to imply absolute orientation .

  As used herein, a noun refers to a plurality of objects unless otherwise specified. Thus, for example, reference to “a component” includes aspects having two or more such components, unless otherwise specified.

  In U.S. Pat. Nos. 5,037,049 and 5,637, at least a plurality of portions of a thin glass sheet are " Solutions are provided that remain in the “unbound” state. However, the periphery of the thin glass is permanently (or covalently or hermetically) bonded to the support glass by the formation of Si—O—Si covalent bonds. This covalently bound perimeter prevents the carrier from being reused. This is because thin glass cannot be removed in this permanently bonded area without damaging the thin glass and carrier.

  In order to maintain convenient surface shape features, the carrier is typically a display grade glass substrate. Thus, in certain situations, simply discarding the carrier after one use is wasteful and expensive. It is therefore desirable to be able to reuse the carrier to process multiple thin sheet substrates in order to reduce display manufacturing costs. The present disclosure relates to high temperature processing (high temperature processing is processing at temperatures above 400 ° C. and varies depending on the type of device being manufactured, eg, 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). Allows thin sheets to be processed through the harsh environment of the included FPD processing line, but still damages the thin sheet or carrier (eg, one of the carrier and the thin sheet breaks or breaks into two or more pieces) Without removing the thin sheet from the carrier more easily, 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 -50 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 or less), and a surface modification layer 30 having a thickness 38. Article 2 has a thin sheet 20 itself of 300 micrometers or less, but a thicker sheet (ie, approximately 0.4 mm or more, for example, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm). , 0.9 mm, or 1.0 mm), designed to be able to process a thin sheet 20 in an apparatus designed for. That is, thickness 8, which is the sum of thicknesses 18, 28, and 38, is designed to be processed by a portion of the apparatus (eg, an apparatus designed to place electronic device components on a substrate sheet). Designed to be equivalent to thicker sheet thickness. For example, if the processing device is designed for a 700 micrometer sheet and the thin sheet has a thickness 28 of 300 micrometers, if the thickness 38 is negligible, the thickness 18 will be 400 micrometers Will be selected. That is, the surface modification layer 30 is not shown to scale; rather, it is greatly exaggerated for illustrative purposes only. Moreover, the surface modification layer is indicated by a notch. In practice, the surface modification layer will be uniformly disposed on the binding surface 14 when providing 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 modified layer will be detected by surface chemical analysis, eg, 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. In the calculation to do, you can ignore. However, as long as the surface modification layer 30 has any significant thickness 38, the thickness 18 of the carrier 10 for the predetermined thickness 28 of the thin sheet 20 and the predetermined thickness for which the processing apparatus is designed. To determine the thickness.

  The carrier 10 has a first surface 12, a binding surface 14, a perimeter 16, and a thickness 18. Further, the carrier 10 can be of any suitable material including, for example, glass. The support need not be glass, but could instead be ceramic, glass ceramic, or metal (surface energy and / or bonding controlled in a manner similar to that described below for glass support. Will be done). If the carrier 10 is made of glass, it can be of any suitable composition including aluminosilicate, borosilicate, aluminoborosilicate, soda lime silicate, depending on the final application. Thus, it may or may not contain an alkali. Thickness 18 is about 0.2 to 3 mm or thicker, for example 0.2, 0.3, 0.4, 0.5, 0.6, 0.65, 0.7, 1.0 , 2.0, or 3 mm, or thicker, depending on thickness 28 and, if not trivial as described above, thickness 38. Moreover, the carrier 10 may be manufactured from one layer or multiple layers bonded together (including multiple thin sheets of the same or different materials) as shown. Further, the carrier may be of a first generation size or larger, eg, 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, a perimeter 26, and a thickness 28. The outer peripheries 16 and 26 may have any shape, and may be the same as or different from each other. Further, the thin sheet 20 may be of any suitable material including, for example, glass, ceramic, or glass ceramic. In some cases, the thin sheet 20 may be a polymer sheet or a composite sheet having a polymer and / or glass bonded surface. If the thin sheet 20 is made of glass, it can be of any suitable composition including aluminosilicate, borosilicate, aluminoborosilicate, soda lime silicate, for final use. Depending on the case, it may or may not contain an alkali. 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 article 2 is processed at a lower temperature where CTE matching is not such a concern, a thin sheet of polymer can be used with a glass carrier. Of course, there may be other examples where a polymer sheet may be used with a glass carrier. The thickness 28 of the thin sheet 20 is 300 micrometers or less as described above. Further, the thin sheet may be of a first generation size or larger, eg, second generation, third generation, fourth generation, fifth generation, eighth generation or larger (eg, 100 mm x 100 mm to 3 meters x 3 meters or larger sheet size).

  Article 2 not only needs to have the exact thickness to be processed in existing equipment, but also sometimes needs to be able to withstand the harsh environment in which the processing takes place. 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 500 ° C. or higher, or 600 ° C. or higher, and up to 650 ° C.

  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 in order to withstand the harsh environment in which the article 2 is processed, such as during FPD manufacturing. It is. This strength should then be maintained throughout processing so that the thin sheet 20 does not separate from the carrier 10 during processing. Further, in order to be able to remove the thin sheet 20 from the carrier 10 (so that the carrier 10 can be reused), the bonding surface 14 is bonded to the bonding surface 24, the initially designed bonding force, and / or, for example, the article is hot. For example, it should not be too strong to be bonded by any of the bond forces that result from a change in the initially designed bond force, such as occurs when processing at temperatures of 400 ° C. or higher. The surface modification layer 30 may be used to control the strength of the bond between the bonding surface 14 and the 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 and van der Waals (and / or hydrogen bond) energy and shared attractive energy relative to the total adhesion energy. This is achieved by controlling This controlled bonding is achieved by FPD processing (wet, ultrasonic, vacuum, and thermal processes including temperatures above 400 ° C, in some cases 500 ° C or above, or 600 ° C and above, and processing temperatures up to 650 ° C. It is strong enough to withstand, and remains peelable by the application of sufficient separation force and by force that does not cause catastrophic damage to the thin sheet 20 and / or carrier 10. Such delamination allows for the removal of the thin sheet 20 and devices fabricated thereon and also allows the carrier 10 to be reused.

  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 the binding 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 case, an important feature of the surface modification layer 30 is that it changes the ability of the bonding surface 14 to bond to the bonding surface 24, thereby controlling the bond 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 prior to bonding can be used to control the bond strength (adhesion energy) between the carrier 10 and the thin sheet 20.

  In general, 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 energy 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: a dispersion component γ ^d and a polar component γ ^p :

If the attachment is primarily due to London dispersion forces (γ ^d ) and polar forces, eg hydrogen bonds (γ ^p ), the interfacial energy is:

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

  Substituting (3) for (1), the adhesion energy is:

Would 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 (Caesom), polar / nonpolar interactions (Debye) and nonpolar / nonpolar interactions (London). However, other attractive energies may exist, such as covalent bonds and electrostatic bonds. So, in a further generalized form, the previous equation is:

Where ω _c and ω _e are the covalent and electroadhesive energies. This covalent attachment energy is fairly common, as in silicon wafer bonds, where the initial hydrogen bond pair of the wafer is heated so high that it converts most or all of the silanol-silanol hydrogen bonds to Si-O-Si covalent bonds. Is. Initial hydrogen bonding at room temperature results in adhesion energies on the order of about 100-200 mJ / m ² that allow separation of the bonding surfaces, as achieved during high temperature processing (approximately 400 to 800 ° C.). A fully covalently bonded wafer pair has an adhesion energy of about 1000 to 3000 mJ / m ^{2 that} prevents separation of the bonded surfaces; instead, the two wafers function as a monolith. On the other hand, if both surfaces are thick enough to shield the influence of the underlying substrate and are fully coated with a low surface energy material, such as a fluoropolymer, the adhesion energy is It will be that of the coating material and will be very small and will result in low or no adhesion between the binding surfaces 14, 24, so that the thin sheet 20 cannot be processed on the carrier 10. Let's go. Consider two extreme cases: (a) Two standard clean 1s saturated with silanol groups attached to each other at room temperature (so that the adhesion energy is about 100-200 mJ / m ² ). A cleaned glass surface (known in the art as SC1), which later converts silanol groups to Si—O—Si covalent bonds (so that the adhesion energy is 1000-3000 mJ / m ² . It is heated to a high temperature. This latter adhesion energy is too high for a pair of glass surfaces to be removable; (2) has a 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 fully coated with fluoropolymer. In this latter case (b), not only does the surface not bind (because the total adhesion energy of about 24 mJ / m ² when the surface is attached is too low), it also has no (or too little) polar reactive groups. Therefore, it does not bond even at high temperatures. There is a range of adhesion energies between these two extreme cases that can produce the desired degree of controlled bonding, for example between 50 and 1000 mJ / m ² . Thus, the inventors of the present application provide a pair of glass substrates (eg, glass carrier 10 and thin glass sheet 20) that are bonded together through the severity of FPD processing, resulting in adhesion energy between these two extreme cases. A controlled bond that can be removed from the carrier 10 after processing is complete (eg, even after high temperature processing at 400 ° C. or higher). Various methods have been found to provide a tunable surface modification layer 30 as can. Furthermore, the removal of the thin sheet 20 from the carrier 10 can be carried out by mechanical force in such a way that at least the thin sheet 20 is not devastatingly damaged, and preferably the carrier 10 is not devastatingly damaged. it can.

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

  Appropriate adhesion energy can be achieved by judicious selection of surface modifiers, i.e., surface modification layer 30, and / or heat treatment of the surface prior to bonding. Appropriate adhesion energy will be obtained by selection of chemical modifiers for either or both of the binding surface 14 and the binding surface 24. The chemical modifier then results from van der Waals (and / or hydrogen bonding, these terms are used interchangeably throughout the specification) attachment energy as well as high temperature processing (eg, above about 400 ° C.). Control both possible covalent bond energies. For example, choosing the binding surface of SC1 cleaned glass (which is initially saturated with silanol groups with a high polarity component of surface energy) and coating it with a low energy fluoropolymer will cause the polar and nonpolar groups to The partial coverage of the surface is controlled. This not only presents control of the initial van der Waals (and / or hydrogen) bonding at room temperature, but also controls the degree / degree of covalent bonding at high temperatures. Control of initial van der Waals (and / or hydrogen) bonding at room temperature allows bonding of one surface to the other, allowing vacuum and / or spin rinse dry (SRD) type processing, And, in some cases, to provide an easily formed bond from one surface to the other. Here, the easily formed bond is applied by 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 a squeegee or by a reduced pressure environment. And can be carried out at room temperature. That is, this initial van der Waals bond is at least a minimal degree that holds the thin sheet and carrier together so that they do not separate if one can be held and the other can be exposed to gravity. Provides a bond. In most cases, the initial van der Waals (and / or hydrogen) bonds are such that the article experiences vacuum, SRD, and sonication without the thin sheet peeling from the support. By the surface modification layer 30 (including the surface treatment of the material from which it is produced and / or the surface on which it is applied) and / or by their heat treatment prior to bonding the bonding surfaces together, van der Waals (and This precise control at the appropriate level of both (and / or hydrogen bonding) and covalent interaction allows the thin sheet 20 to be bonded to the carrier 10 throughout FPD style processing, while at the same time after FPD style processing. A desired adhesion energy is achieved that allows the thin sheet 20 to be separated 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 adhesion energy.

  FPD processing, such as p-Si and oxide TFT fabrication, will typically result in glass-to-glass bonding of the thin glass sheet 20 to the glass carrier 10 without the surface modification layer 30. , Over 400 ° C., over 500 ° C., and in some cases, thermal processing at temperatures of 600 ° 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 high temperatures is to reduce the concentration of surface hydroxyls on the surfaces to be bonded.

  Iller plot of surface hydroxyl concentration on silica as a function of temperature (RK Iller: The Chemistry of Silica (Wiley-Interscience, New York, 1979)), as shown in FIG. Thus, heating the silica surface (and illustratively, the glass surface, eg, the binding surface 14 and / or the binding surface 24) reduces the concentration of surface hydroxyls with increasing surface temperature. This reduces the probability that hydroxyls on the two glass surfaces will interact, which in turn reduces the Si—O—Si bonds formed per unit area and reduces the adhesion force. However, to eliminate surface hydroxyls, long temperatures at high temperatures (above 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 discovered that an article with a thin sheet and carrier suitable for FPD processing (including LTPS processing) can be produced 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 processing, SRD processing, and / or sonication (e.g., prior to bonding surfaces) By controlling the initial initial room temperature bonding, which can be done by controlling van der Waals (and / or hydrogen) bonding to produce a surface energy of greater than 40 mJ / m ² per surface) And / or modification of the bonding surface of the thin sheet;
(2) Thermal enough to withstand an FPD process without degassing and / or unacceptable contamination in device manufacturing, for example, outgassing that may cause unacceptable contamination in the semiconductor and / or display manufacturing process 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 high temperatures (eg, temperatures above 400 ° C.) Between the support 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). Adhesive strength will not damage at least the thin sheet (and preferably neither the thin sheet nor the carrier will be damaged) ) The carrier can be separated so that the thin sheet can be peeled from the carrier, but still remains within a range that is sufficient to maintain the bond between the carrier and the thin sheet so that they do not peel during processing. And high temperature bond control that can control the bond energy between the bond surfaces of thin sheets.

  In addition, the inventors have used a surface modification layer 30 along with the treatment of the bonding surface, if necessary, to control the bonded area, ie, the article 2 to an FPD type process (vacuum and wet processes). Provide sufficient room temperature bonding between the thin sheet 20 and the carrier 10, but still after the article 2 has undergone 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 found that the above-described concept can be balanced to easily achieve a bond zone (even at temperatures higher than 400 ° C.). A series of tests were used to evaluate potential bonded surface treatments and surface modified layers that would provide a reusable support suitable for FPD processing. Although different FPD fields have different requirements, LTPS and oxide TFT processes appear to be the most demanding at this point, and therefore these processes are desirable applications for article 2, so the steps in these processes A representative test was 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, certain bonding surface treatments and surface modification layers 30 can leave the thin sheet 20 bonded to the carrier 10 throughout FPD processing while such processing (including processing at temperatures above 400 ° C.). To evaluate the tendency that the thin sheet 20 could later be removed from the carrier 10 (without damaging the thin sheet 20 and / or the carrier 10), the following five tests were used. Those tests were conducted in order, and the samples were advanced from one test to the next unless there was a type of breakage that would not allow subsequent tests.

  (1) Vacuum test. The vacuum compatibility test was performed in an STS Multiplex PECVD loadlock (obtained from SPTS, Newport, UK)-this loadlock was an Ebara A10S dry pump with a soft pump valve (Sacramento, CA). From Ebara Technologies Inc.). The sample was placed in the 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 (considerable failure occurred when the thin sheet was peeled off from the carrier or partially peeled off by visual inspection with the naked eye); 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 increases with visible dimensions, Or (c) moving the thin sheet relative to the carrier (determined by visual observation with the naked eye-the sample was photographed before and after the test and adhesion defects such as bubbles moving or edges were In the case of peeling, or when a thin sheet moves on the carrier, it is considered that a defect has occurred). 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 testing was performed using Semitool model SRD-470S (obtained from Applied Materials, Santa Clara, Calif.). The test consisted of rinsing at 500 rpm for 60 seconds, Q rinsing to 15 MΩ · cm at 500 rpm, purging at 500 rpm for 10 seconds, drying at 1800 rpm for 90 seconds, and 2400 rpm under warm nitrogen flow for 180 seconds. Drying in. (A) Loss of adhesion between the carrier and the thin sheet (considerable failure occurred when the thin sheet was peeled off from the carrier or partially peeled off by visual inspection with the naked eye); 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 increases with visible dimensions, Or (c) moving the thin sheet relative to the carrier (determined by visual observation with the naked eye-the sample was photographed before and after the test and adhesion defects such as bubbles moving or edges were When peeling or when the thin sheet moved on the carrier, it was considered that a malfunction occurred; or (d) water permeability under the thin sheet (by 50 times optical microscope) If it is determined by visual inspection, liquid or residue can be observed, and it is determined that a defect has occurred), it is considered impossible to be represented by the notation “F” in the “SRD” column of the table below It 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. The suitability test for the 400 ° C. process was performed using Alwin 21 Accuthermo 610 RTP (obtained from Alwin 21 of Santa Clara, Calif.). The thin sheet bonded carrier 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 thin sheet were then cooled to room temperature. (A) Loss of adhesion between the carrier and the thin sheet (considerable failure occurred when the thin sheet was peeled off from the carrier or partially peeled off by visual inspection with the naked eye); 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 increases with visible dimensions, Or (c) increased adhesion between the carrier and the thin sheet, such increased adhesion may cause the thin sheet or carrier to delaminate without damaging the thin sheet or carrier. Blocked (by insertion of a razor blade between the thin sheet and the carrier and / or on the thin sheet with Kapton ™ tape (Sain, Hosick, NY) A piece of K102 series from Gobain Performance Plastic (1 inch (about 2.5 cm) wide x 6 inch (about 15 cm) affixed 2-3 inches (about 5 to 7.5 cm) on 100 mm2 thin glass) Long sheet) and by pulling the tape), if an attempt is made to separate the thin sheet or carrier, the thin sheet and carrier will be If it could not be peeled off, it was considered that a defect occurred: if there was, it was considered that it became impossible to be represented by the notation “F” in the column of “400 ° C.” in the table below. In addition, after bonding a thin sheet to a carrier and prior to thermal cycling, a representative sample is subjected to a peel test to ensure that certain materials, including any associated surface treatment, are thin prior to thermal cycling. It was determined that the sheet could be peeled 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 for the 600 ° C. process was performed using Alwin21 Accuthermo610 RTP. The carrier with a 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 thin sheet were then cooled to room temperature. (A) Loss of adhesion between the carrier and the thin sheet (considerable failure occurred when the thin sheet was peeled off or partially peeled off from the carrier by visual inspection with the naked eye); 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 increases with visible dimensions, Or (c) increased adhesion between the carrier and the thin sheet, such increased adhesion would cause the thin sheet or carrier to peel off without damaging the thin sheet or carrier. A piece of “Kapton” tape as described above by inserting a razor blade between the thin sheet and the carrier and / or on 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 and carrier could not be peeled by any of the peeling methods, a failure occurred. Thought: When there was, it was considered impossible to be represented by the notation “F” in the column of “600 ° C.” in the table below. In addition, after bonding a thin sheet to a carrier and prior to thermal cycling, a representative sample is subjected to a peel test to ensure that certain materials, including any associated surface treatment, are thin prior to thermal cycling. It was determined that the sheet could be peeled 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. The ultrasonic compatibility test was performed by washing the article in a line of 4 tanks. Here, articles were processed in each of successive tanks from tank # 1 to tank # 4. The tank dimensions for each of the four tanks were 18.4 inches long x 10 inches wide x 15 inches deep. The two wash tanks (# 1 and # 2) contained 1% Semiclean KG obtained from Yokohama Oil & Fat Co., Ltd., Yokohama, Japan, in 50 ° C. deionized water. Wash tank # 1 was agitated by a NEY prosonic 2 104 kHz ultrasonic generator (obtained from Blackstone-NEY Ultrasonics, Jamestown, NY), and wash tank # 2 was also a Ny prosonic 2 104 kHz ultrasonic generator. Stir. Two rinse tanks (Tank # 3 and Tank # 4) contained 50 ° C. deionized water. Wash tank # 3 was agitated with a NEE sweepsonic 2D 72 kHz ultrasonic generator, and wash tank # 4 was agitated with a NEE sweepsonic 2D 104 kHz ultrasonic generator. The process was run for 10 minutes in each of tanks # 1-4, after which the sample was removed from tank # 4 and then spin-rinse-dried (SRD). (A) Loss of adhesion between the carrier and the thin sheet (considerable failure occurred when the thin sheet was peeled off from the carrier or partially peeled off by visual inspection with the naked eye); 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 increases with visible dimensions, Or (c) formation of other gross defects (determined by visual inspection with a 50x optical microscope, particles not previously observed between thin glass and carrier) (D) Permeability under a thin sheet (determined by visual inspection with a 50x optical microscope, if a liquid or residue could be observed, In the following table, the “ultrasonic” column indicated that it was indicated as “F”. In the table below, the notation “P” in the “Ultrasound” column indicates that the sample was not disabled by the criteria described above. In addition, in the table below, the blank in the “Ultrasound” column indicates that the sample was not tested in this manner.

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

The binding energy was measured using the double cantilever method (also known as the wedge method). In this method, a known thickness of wedge is placed at an angle between the bonded thin sheet and the carrier glass. The wedge causes a characteristic peeling 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 EXG composition carrier (1) and thin sheet (2) 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-divided with another wedge. This facilitates the insertion of the wedge and the formation of the characteristic peel length. For the reported binding energy data, a value of 2500 represents the test limit condition, indicating that for that particular sample, a thin sheet could not be peeled from the carrier.

The treated surface 2 of the bonded surface through hydroxyl reduction by heating can successfully experience FPD processing (ie, the thin sheet 20 remains bonded to the support 10 during processing but still after processing including high temperature processing. The benefit of modifying one or more of the binding surfaces 14, 24 with the surface modification layer 30 is the article 2 having the glass carrier 10 and the thin glass sheet 20 without the surface modification layer 30 in between. Indicated by processing. Specifically, first, the treatment of the binding surfaces 14 and 24 was tried without the surface modification layer 30 but by heating to reduce hydroxyl groups. 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 glass for bonding involves diluting the glass with hydrogen peroxide and base (usually ammonium hydroxide, but tetramethylammonium hydroxide solution such as JT Baker JTB-100. (Or JTB-111 may also be used). Washing removes particles from the binding surface and provides a surface energy reference, ie, a measure of surface energy. Other types of cleaning may be used, as the cleaning mode does not have to be SC1 and the type of cleaning appears to have a negligible 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, each averaged from Eagle XG® display glass (Corning Incorporated, Corning, NY) A thin glass sheet of 100 square mm × 100 μm thickness, and a single of 150 mm in diameter with a thickness of 0.50 or 0.63 mm, made of a non-alkali aluminoborosilicate glass having a surface roughness Ra of about 0.2 nm • Generated by simply cleaning the glass support of a single mean flat (SMF) wafer. In this example, the glass was cleaned in a 65 ° C. bath of 40: 1: 2 deionized water: JTB-111: hydrogen peroxide for 10 minutes. This thin glass or glass support may or may not be annealed in nitrogen for 10 minutes at 400 ° C. to remove residual water—the “support” column in Table 1 below or “thin glass” The “400 ° C.” notation in the column indicates that the sample was annealed in nitrogen at 400 ° C. for 10 minutes. FPD process compatibility testing shows that this SC1-SC1 initial, room temperature, bond is mechanically strong enough to pass vacuum, SRD and ultrasonic testing. However, heating above 400 ° C formed a permanent bond between the thin glass and the carrier, i.e., the thin glass sheet does not damage either or both of the thin glass sheet and the carrier. , Could not be removed from the carrier. And this was true even for Example 1c, where the support and thin glass were each annealed to reduce the concentration of surface hydroxyl. Therefore, 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 using the surface modification layer 30, is appropriately controlled for the FPD process where the temperature is 400 ° C. or higher. Is not a combined.

Treatment of the binding surface with hydroxyl reduction and surface modification layer For example, the reduction of hydroxyl, such as by heat treatment, and the surface modification layer 30 may be used together to control the interaction of the binding surfaces 14, 24. Good. For example, the binding energy of the binding surfaces 14, 24 (both van der Waals and / or hydrogen bonding at room temperature due to polar / dispersive energy components and covalent bonding at high temperatures due to covalent energy components) It can be controlled to provide a variety of bond strengths, from difficult strengths to strengths that prevent separation of surfaces without damage-after high temperature processing. In some applications, the bond is very weak or not at all (if the surface is in the “non-bonded” region, the “non-bonded” region 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 FPD processes and the like (500 ° C. or higher, or 600 ° C. or higher and may be up to 650 ° C. process temperature) It is desirable to have van der Waals and / or hydrogen bonds at room temperature sufficient to attach the supports together, yet prevent or limit high temperature covalent bonds. For still other applications, it has a room temperature bond that is initially sufficient to attach the thin sheet and the carrier together and also produces a strong covalent bond at high temperatures (if the surface is in the “bonding region” It may be desirable for the “bond 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 modified layer may be used to control the bonding at room temperature by which the thin sheet and carrier are first attached to each other, whereas 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 modification layer 30 provides energy that causes only weak bonding on the surface (eg, includes energy less than 40 mJ / m ^{2 as} measured for one surface, polarity and dispersion components). Would give to. In one example, hexamethyldisilazane (HMDS) may be used to form this low energy surface by reacting with surface hydroxyl to leave a trimethylsilyl (TMS) terminal surface. HMDS as a surface modification layer may be used with surface heating to reduce the hydroxyl concentration to control both room temperature and high temperature bonding. By selecting an appropriate bonding surface treatment for each bonding surface 14, 24, articles having various ranges of capabilities can be achieved. More particularly, for providing a reusable carrier for LTPS processing, it is interesting to note that each of the vacuum, SRD, 400 ° C. (items a and c), and 600 ° C. (items a and c) processing tests. Appropriate bonding can be achieved between the thin glass sheet 20 and the glass carrier 10 to withstand (pass).

  In one example, SC1 cleaning of both a thin glass sheet and a glass carrier followed by HMDS treatment creates a weakly bonded surface that can be bonded at room temperature by van der Waals (and / or hydrogen bonding) forces. difficult. A mechanical force is applied to bond the thin glass to the carrier. As shown in Example 2a of Table 2, this binding is observed for carrier warpage in vacuum testing and SRD processing, and in the thermal processes at 400 ° C. and 600 ° C. bubble formation (which may be due to outgassing). And granular defects are weak enough that they were observed after sonication.

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

  Prior to HMDS exposure, heating the glass surface to reduce the surface hydroxyl concentration can create altered surface energy and increase the polar component of the surface energy. Both of these reduce the driving force for forming Si—O—Si covalent 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 (polarity and dispersion) surface energy (line 402) after HMDS exposure by increasing the polarity contribution (line 404). It can also be seen that the contribution of dispersion to the total surface energy (line 406) remains largely unchanged by heat treatment. While not intending to be bound by theory, the polar component of energy at the surface after HMDS treatment, and hence the increase in total energy, is somewhat due to TMS coverage of the submonolayer by HMDS, even after HMDS treatment. 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 1 hour prior to bonding with a non-heat treated support having a coating of HMDS. This heat treatment of the thin glass sheet was not sufficient to prevent the thin glass sheet from permanently binding to the support at temperatures above 400 ° C.

  As shown in Table 2 examples 2c-2e, 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 support and the thin glass sheet. be able to.

  In Example 2c, the support was annealed in vacuum at a temperature of 190 ° C. for 1 hour, after which HMDS exposure was performed to provide the surface modified layer 30. In addition, the thin glass sheet was annealed at a temperature of 450 ° C. in a vacuum for 1 hour prior to bonding with the support. The resulting article withstood the vacuum, SRD, and 400 ° C tests (items a and c, but did not pass item b because of increased bubble generation), but the 600 ° C test It was impossible. Thus, compared to Example 2b, the resistance to high temperature bonding was increased, but this was not sufficient to produce articles for processing above 600 ° C. (eg LTPS processing) where the carrier could be reused. It was.

  In Example 2d, the support was annealed at a temperature of 340 ° C. in a vacuum for 1 hour, after which HMDS exposure was performed to provide the surface modified layer 30. Once again, the thin glass sheet was annealed at a temperature of 450 ° C. in vacuum for 1 hour prior to bonding with the support. The results are similar to those of 2c, and the article withstood the vacuum, SRD, and 400 ° C. tests (items a and c, but did not pass item b because of increased bubble generation). However, the test at 600 ° C. was not possible.

  As shown in Example 2e, both the thin glass and the support are annealed at 450 ° C. in vacuum for 1 hour, after which the support is exposed to HMDS, and then the support and the thin glass sheet are bonded to make the permanent Temperature resistance to unfavorable bonding is improved. Annealing both surfaces to 450 ° C. prevents permanent bonding after RTP annealing at 600 ° C. for 10 minutes, ie the sample passed the 600 ° C. treatment test (items a and c, but Item b was not passed because of 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 is “Eagle XG” glass, the carrier is a SMF wafer having a thickness of 630 micrometers and a diameter of 150 mm, and the thin sheet is 100 square mm × It was 100 micrometers thick. The HMDS was applied by pulse deposition in a YES-5 HMDS oven (obtained from Yiel Engineering Systems, San Jose, Calif.) And was one atomic layer thickness (ie, about 0.2 to 1 nm), The surface coverage will be less than 1 monolayer, ie, some of the surface hydroxyls are not covered by HMDS as shown by Maciel and discussed above. Because of the small thickness of the surface modification layer, there is little risk of outgassing that can cause contamination in device manufacturing. Also, as shown in Table 2 by the designation “SC1”, each of the carrier and 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. Binding energy control can then be used to control the binding force between the two binding surfaces. Also, the comparison of Examples 2b-2e shows that the surface binding energy can be controlled by changing the parameters of the heat treatment applied to the binding surface prior to the application of the surface modified layer. Again, heat treatment can be used to reduce the number of surface hydroxyls and control the degree of covalent bonding, particularly at high temperatures.

Other materials that will function in different ways to control the surface energy on the binding surface are used in the surface modification layer 30 to control the bonding force between the two surfaces at room and high temperatures May be. For example, one or both binding surfaces may cover chemical species such as hydroxyl or sterically hinder surface modification to prevent the formation of strong permanent covalent bonds between the support and the thin sheet at high temperatures. A carrier that can be reused can also be made if it is modified with a stratified layer to create a moderate bond strength. One way to create a surface energy that can be prepared and to cover the surface hydroxyl and prevent the formation of covalent bonds is the deposition of a plasma polymer film, such as a fluoropolymer film. Plasma polymerization can be accomplished with a feed gas such as a fluorocarbon 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 hydrochloro Fluorocarbons), hydrocarbons such as alkanes (including methane, ethane, propane, butane), alkenes (including ethylene, propylene), alkynes (including acetylene), and aromatics (including benzene, toluene) , Hydrogen, and other gas sources, eg, plasma excitation from atmospheric pressure or reduced pressure from SF ₆ (DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF A polymer film is deposited by plasma. Plasma polymerization produces a layer of highly cross-linked material. Reaction conditions and feed gas control can be used to control film thickness, density, and chemistry to tailor the functional group to the desired application.

FIG. 5 shows the total (line 502) of a plasma polymerized fluoropolymer (PPFP) film deposited from a CF ₄ -C ₄ F ₈ mixture with an Oxford ICP380 etching apparatus (obtained from Oxford Instruments, Oxfordshire, UK). The surface energy (including polar (line 504) and dispersion (line 506) components) is shown. The films were deposited on a sheet of “Eagle XG” glass and spectroscopic ellipsometry showed that the films were 1-10 nm thick. As can be seen from FIG. 5, the glass support treated with a plasma polymerized fluoropolymer film containing less than 40% C ₄ F ₈ exhibits a surface energy of greater than 40 mJ / m ² , due to van der Waals or hydrogen bonding at room temperature. A controlled bond between the thin glass and the carrier. Accelerated binding is observed when the support and thin glass are first bonded at room temperature. That is, when thin sheets are placed on a carrier and pressed together at some point, the rate is slower than that observed for an SC1-treated surface that does not have a surface modification layer on it, 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 support The glass passed the 600 ° C. treatment test without moving or peeling. Peeling was performed by peeling with a razor blade and / or “Kapton” tape as described above. The process compatibility of two different PPFP films (deposited as described above) is shown in Table 3. The PPFP1 of Example 3a was formed with C ₄ F ₈ / (C ₄ F ₈ + CF ₄ ) = 0, ie formed with CF ₄ / H ₂ instead of C ₄ F ₈ , and PPFP2 of Example 3b Deposited at ₄ F ₈ / (C ₄ F ₈ + CF ₄ ) = 0.38. Both types of PPFP films withstood vacuum, SRD, 400 ° C. and 600 ° C. processing tests. However, delamination is observed after 20 minutes ultrasonic cleaning of PPFP2, 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 the previous examples 3a and 3b, each of the carrier and thin sheet is “Eagle XG” glass, the carrier is an SMF wafer 630 micrometers thick and 150 mm in diameter, and the thin sheet is 100 square mm × It was 100 micrometers thick. Because of the small thickness of the surface modification layer, there is little risk of outgassing that can cause contamination in device manufacturing. Furthermore, since the surface modified layer appeared not to deteriorate, the risk of outgassing is even less. Also, as shown in Table 3, each of the thin sheets was cleaned using the SC1 process prior to heat treatment at 150 ° C. for 1 hour in vacuum.

Still other materials that may function in different ways to control the surface energy may be used as a surface modification layer to control the bonding force between the thin sheet and the carrier at room and high temperatures. Good. For example, a bonding surface capable of producing controlled bonding can be formed by silane treatment of 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. The support or thin glass to be treated is used to remove organic materials and other impurities (eg, metals) that would interfere with the reaction of the silane with surface silanol groups, such as O ₂ plasma or You may clean with UV-ozone and SC1 or Standard Clean 2 (known in the art as SC2). Other chemical based cleaning fluids may be used, such as HF or H ₂ SO ₄ cleaning chemicals. The support or thin glass may be heated to control the surface hydroxyl concentration prior to silane application (as described above with respect to the surface modification layer of HMDS) and / or silane condensation with the surface hydroxyl. To complete, it may be heated after application of the silane. The concentration of unreacted hydroxyl groups after the silane treatment is such that the temperature before 400 ° C. is increased so as to prevent permanent bonding between the thin glass and the carrier, that is, to form a controlled bond. May be sufficiently low. This approach is described below.

Example 4a
The glass substrate treated with O ₂ plasma and SC1 on the binding surface was then treated with 1% dodecyltriethoxysilane (DDTS) in toluene and annealed at 150 ° C. in vacuum for 1 hour to complete the condensation. did. The DDTS treated surface exhibits a surface energy of 45 mJ / m ² . As shown in Table 4, a thin sheet of glass (SC1 cleaned and heated at 400 ° C. in vacuum for 1 hour) was bonded to the binding surface of a carrier having a DDTS surface modification layer thereon. This article withstood wet and vacuum process tests, but due to the thermal decomposition of silane, it did not withstand thermal processes above 400 ° C. without forming bubbles under the support. This pyrolysis results in all linear alkoxy and chloroalkyl silanes R1 _x Si (except for methyl, dimethyl, and trimethylsilane (x = 1 to 3, R1 = CH ₃ ) resulting in a good heat stable coating. OR2) predicted for _y (Cl) _z (x = 1 to 3, y + z = 4-x).

Example 4b
The glass substrate treated with O ₂ plasma and SC1 on the binding surface was then treated with 1% 3,3,3-trifluoropropyltriethoxysilane (TFT) in toluene and 150 ° C. in vacuo for 1 hour. To complete the condensation. The TFTS treated surface exhibits a surface energy of 47 mJ / m ² . As shown in Table 4, a thin sheet of glass (SC1 cleaned and then heated at 400 ° C. in vacuum for 1 hour) was bonded to the binding surface of a carrier having a TFTS surface modification layer thereon. . This article withstood vacuum, SRD, and 400 ° C. process tests without a thin sheet of glass permanently bonded to the glass carrier. However, in the 600 ° C. test, bubbles were formed under the support due to the thermal decomposition of silane. This was not unexpected due to the limited thermal stability of the propyl group. Although this sample was not capable of 600 ° C. testing due to bubble generation, the materials and heat treatments of this example can tolerate bubbles and their adverse effects, such as reduced surface flatness or increased undulations. May be used for several applications.

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

Example 4d
The glass substrate treated with O ₂ plasma and SC1 on the binding surface was then treated with 1% diphenyldiethoxysilane (DPDS) in toluene and annealed at 200 ° C. in vacuum for 1 hour to complete the condensation. did. The DPDS treated surface exhibits a surface energy of 47 mJ / m ² . As shown in Table 4, a thin sheet of glass (SC1 cleaned and then heated at 400 ° C. in vacuum for 1 hour) was bonded to the binding surface of the support with the DPDS surface modification layer. This article withstood vacuum and SRD testing and thermal processes up to 600 ° C. without a thin sheet of glass permanently bonded to the glass carrier.

Example 4e
The glass surface treated with O ₂ plasma and SC1 was then treated with 1% 4-pentafluorophenyltriethoxysilane (PFPTS) in toluene and annealed at 200 ° C. in vacuo for 1 hour. The condensation was complete. The PFPTS treated surface exhibits a surface energy of 57 mJ / m ² . As shown in Table 4, a thin sheet of glass (SC1 cleaned and then heated at 400 ° C. in vacuum for 1 hour) was bonded to the binding surface of the support with the PFPTS surface modification layer. This article withstood vacuum and SRD testing and thermal processes up to 600 ° C. without a thin sheet of glass permanently bonded to the glass carrier.

  In the previous examples 4a to 4e, each of the carrier and the thin sheet is “Eagle XG” glass, the carrier is a SMF wafer having a thickness of 630 micrometers and a diameter of 150 mm, and the thin sheet is 100 square mm × It was 100 micrometers thick. The silane layer was a self-assembled monolayer (SAM) and therefore had a thickness on the order of less than about 2 nm. In the above examples, the SAM was formed using an organosilane having an aryl or alkyl nonpolar 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 organic layer is organized by weak interactions between nonpolar head groups. Due to the small thickness of the surface modification layer, there is little risk of outgassing that can cause contamination in device manufacturing. Furthermore, the surface modification layer appeared to not deteriorate in Examples 4c, 4d, and 4e, so the risk of outgassing is even less. Also, as shown in Table 4, each thin glass sheet was cleaned using the SC1 process prior to heat treatment at 400 ° C. for 1 hour in vacuum.

As can be seen from the comparison of Examples 4a to 4e, controlling the surface energy of the bonding surface to be greater than 40 mJ / m ² to withstand initial room temperature bonding can withstand FPD processing and still damage It is not the only consideration for creating a controlled bond that allows the thin sheet to be removed from the carrier without it. Specifically, as can be seen from Examples 4a-4e, each support has a surface energy of greater than 40 mJ / m ² , which provides an initial bonding at room temperature so that the article can withstand vacuum and SRD processing. Was promoted. However, Examples 4a and 4b did not pass the 600 ° C. treatment test. As noted above, for certain applications, the bond was designed to be used at high temperatures (eg, articles are used without degrading to a point where it is insufficient to hold the thin sheet and carrier together. Such high temperatures that it can withstand processing up to 400 ° C or higher, 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 examples in Table 4, aromatic silanes, particularly phenyl silanes, promote controlled initial room temperature bonding, withstand FPD processing, and still be able to remove thin sheets from the carrier without damage. Useful for providing additional bonds.

Another example of using a fluorocarbon surface modification layer and its treated plasma polymerized film to adjust the surface energy of the binding surface and create an alternative polar binding site thereon is a mixture of fluorocarbon gas sources Depositing a thin film of the surface modified layer from the substrate, and then forming nitrogen-based polar groups on the surface modified layer by using various methods.

The surface modification layer is S.I. The theoretical model developed by Wu (1971) was calculated by fitting the contact angle (CA) of three different test liquids, in this case deionized water (water), hexadecane (HD), and diiodomethane (DIM). May be formed by plasma polymerization of various mixtures of fluorocarbon gas sources to provide various surface energies, including surface energies greater than about 50 mJ / m ² (reference: S. Wu, J. Polym Sci. C, 34, 19, 1971; hereinafter referred to as “Wu model”). A surface energy above about 50 mJ / m ² on the binding surface of the carrier is beneficial for bonding the carrier to a thin glass sheet. This is because it facilitates the initial room temperature bonding of the support to the thin glass sheet and allows the FPD processing of the support / thin glass sheet without peeling them during the process. In some cases, depending on the composition of the surface modification layer and the deposition conditions, the surface modification layer with this surface energy will have the support and thin glass sheet at temperatures up to about 600 ° C., and in some cases even higher. Even after processing at temperature, it can be peeled off by peeling. In general, 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 FIG. 5 and FIG. 13, in general, the lower the proportion of polymer-forming gas, the greater the total surface energy 502, 1312 of the resulting binding surface, where the total surface energy is A combination of polar components 504, 1314 (triangular data points) and variance components 506, 1316 (square data points). The proportion of polymer-forming gas (eg, CHF ₃ ) during plasma polymerization is by using an inert gas (eg, Ar) as shown in FIG. 13A, which shows the total surface energy in mJ / m ² . In order to control the resulting surface energy, it will be similarly controlled. While not intending to be bound by theory, the inert gas may act as an etchant, a 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 containing CF _{4 in the} gas flow. The deposition of the surface modification layer may be performed under atmospheric pressure or reduced pressure, and plasma excitation such as DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF Performed by plasma. The plasma polymerized surface modification layer may be deposited on the support, thin sheet, or both. As described above for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Reaction conditions and feed gas control can be used to control the thickness, density, and chemistry for tailoring the functional groups to the desired application. The surface energy of the binding surface of the carrier can be adjusted by controlling the properties of the film. 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 way to control polar coupling is to subject the surface modification layer (formed as before) to a further treatment to include polar groups, such as treatment with nitrogen-containing plasma. . This treatment increases adhesion by forming nitrogen-based polar functional groups on the thin surface modified layer. The nitrogen-based polar groups formed during this subsequent process do not condense with the silanol groups to form permanent covalent bonds and are therefore used to deposit films or structures on thin sheets. During subsequent processing, the degree of bonding between the thin sheet and the carrier can be controlled. Examples of methods for forming nitrogen-based polar groups include nitrogen plasma treatment (Examples 5b-d, k, l), ammonia plasma treatment (Examples 5e, f, hj), and nitrogen / hydrogen plasma treatment (Example 5m). ).

It is observed that thin glass sheets and glass supports bonded by surface modified layers treated with nitrogen-containing plasma do not permanently adhere after annealing at 600 ° C., ie they are at a temperature of 600 ° C. Pass test item (c). This moderate bond is also strong enough to withstand FPD processing (including the vacuum test (1), wet process test (2), and ultrasonic test (5) described above) and sufficient peel force It remains peelable by application of. Peeling allows removal of devices made on thin glass and reuse of the carrier. Nitrogen plasma treatment of the surface modification layer will obtain one or more of the following advantages: minimal bubble defects after the first bond, leading to strong adhesion between the thin sheet and the support, High surface energy and low water contact angle (see Examples 5b-f and i-1); reduced defect formation when heat treated due to improved thermal stability of surface modified layer (Example 5c, Samples treated with 5d, 5k, 5l, ie N ₂ , visually observed to show reduced bubble formation); and / or due to separation of the surface modification layer formation and treatment, Easier process windows (examples 5f-f and hm) as different processes are possible to optimize the quality layer as well as the surface modification layer / thin glass interface. That is, the basic 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, separately, after depositing the surface modified layer on the support, the nature of the surface modified layer is to optimize the interaction of the surface modified layer with the thin sheet to be placed thereon. You may change with processing.

In the example of Table 5 below, various conditions were used to deposit the plasma polymerized film on the glass support. The glass support was a substrate made from Corning® “Eagle XG” (obtained from Corning Incorporated, Corning, NY), an aluminoborosilicate alkali-free display glass. Prior to deposition of the surface modified layer, the support was cleaned using SC1 and / or SC2 chemistry and standard cleaning techniques. The film was deposited in an Oxford Plasmalab 380 Inductively Coupled Plasma (ICP) system equipped with both coil and platen 13.56 MHz RF source, and the platen temperature was fixed at 30 ° C. Samples 5a-5j were subjected to nitrogen and ammonia plasma treatment of the surface modified layers in a 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, to which a specific wattage of 13.5 MHz RF energy is placed. Was applied. For energy applied to both Oxford ICP and STS PECVD, the number is 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 that of the top electrode. The gas flow rate into the vessel was as shown in Table 5 (flow rate is cubic centimeters per minute-sccm under standard conditions). Thus, for example, the notation in the “Surface Treatment” column of Table 5 for Example 5g can be read as follows: In an Oxford ICP device, in a vessel with a pressure of 5 millitorr (about 0.67 Pa), a CF of 30 sccm ₄ , 10 sccm of C ₄ F ₈ and 20 sccm of H ₂ were flushed together; 1000 W of 13.5 MHz RF energy was applied to the coil and 50 W of 13.56 MHz RF energy was applied to the carrier. Applied to a platen at 30 ° C .; the deposition time was 60 seconds. The surface treatment column notation for the remaining examples can be read similarly. As yet another example, in the “plasma treatment” column, the treatment notation of example 5h can be read as follows: after forming the surface modified layer according to the parameters of the surface treatment column of example 5h, then Supply 100 sccm of NH ₃ to an STS PECVD bath with a pressure of 1 Torr (about 133 Pa) and a temperature of 200 ° C .; apply 100 W of 13.56 MHz to the showerhead; and perform the treatment for 30 seconds. The “Plasma Processing” column notation for the remaining examples can be read similarly. The surface energy of both polar and dispersive components fits the Wu model to the contact angle (CA) of three different test liquids, in this case deionized water (water), hexadecane (HD), and diiodomethane (DIM). From mJ / m ² (millijoule per square meter). For surface energy, the polar (P) and dispersed (D) components and the total (T) are shown.

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

Example of treatment with NH ₃ plasma (5e, f, and hj)
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), and another with a 1000 W coil and a 50 W platen RF output at 30 sccm CF ₄ , 10 sccm C ₄ F ₈ , 20 sccm at 5 millitorr (about 0.67 Pa). Of H ₂ (control 5 g). The surface energy of the untreated fluoropolymer film is shown in Table 5. Samples were transferred to an STS PECVD system and exposed to ammonia plasma under the conditions listed in Table 5 (Examples 5e, 5f, 5h-j). The surface tension measured with deionized water and hexadecane according to the Wu equation increased from about 40 to about 65-80 mJ / m ² depending on the ammonia plasma conditions. A thin glass sheet was bonded to each of these NH ₃ plasma modified samples. After the temperature test at 600 ° C., little change in the bubble area was visually observed (no formal gas release test was performed), and in all of these samples the thin glass sheets were easily peeled off by hand.

Example of treatment with N ₂ plasma (5c, d, k, l)
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), and another with a 1000 W coil and a 50 W platen RF output at 30 sccm CF ₄ , 10 sccm C ₄ F ₈ , 20 sccm at 5 millitorr (about 0.67 Pa). Of H ₂ (control 5 g). The surface energy of the untreated fluoropolymer film is shown in Table 5. Samples 5c, d, k, l were N ₂ plasma treated in situ in the 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 the 600 ° C. temperature test, the thin glass sheets of all these samples were easily peeled off by hand.

Example of treatment with simultaneous N ₂ and H ₂ plasma (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 5g). The surface energy of the untreated fluoropolymer film is shown in Table 5. Sample 5m was subjected to N ₂ + H ₂ plasma treatment simultaneously in situ in the 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 film is shown in Table 5. This sample was then subjected to N ₂ and H ₂ plasma treatments continuously in situ in the ICP system under the conditions listed in Table 5. The surface energy increased to over 70 mJ / m ² . This value is comparable to that obtained with ammonia or nitrogen plasma. A thin glass sheet was bonded to the 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. treatment test.

  XPS data revealed the effect of ammonia and nitrogen plasma treatment on the surface modification 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 seen to increase as well, consistent with an ammonia plasma that removes the fluoropolymer while adding a small amount of nitrogen species to the surface. Nitrogen plasma treatment increases the nitrogen content to 2 at%, but also reduces the carbon and fluorine content as well as ammonia. Silicon, oxygen and other glass components also increase consistent with the 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. As a result of the surface modification layer, the thickness 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 noted above, the thin glass sheet bonded to the carrier as in the example of Table 5 is an aluminoborosilicate alkali-free glass, “Corning” Willow® Glass (Corning Incorporated, Corning, NY). Substrate having a thickness of 100, 130, and 150 micrometers. Prior to bonding, the “Willow” 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 with the surface modified layer disposed thereon was glass, but this is not necessary. Alternatively, the bonding surface may be another suitable material having surface energy and properties similar to glass, such as silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

  The use of a plasma polymerized fluoropolymer surface modification layer with a thickness of less than 20 nm to control the binding energy of the glass binding 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 modification layer on top 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 between the polar groups on the thin glass sheet (mainly silanol groups) and the polar groups on the surface modification layer of the support, with or without hydrogen-bonded molecular water. It is a dipole-to-dipole (Keesom) interaction. However, the fluoropolymer surface modification process prevents the thin sheet from permanently bonding to the carrier at temperatures up to 600 ° C. associated with device manufacturing. In order to provide an overwhelming cost advantage over the low yield acid thinning of thicker glasses, the support needs to be reused. Since the fluoropolymer deposition process etches the surface of the support, this is a concern when using a fluorinated surface modification layer. Recycling of the 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 the binding energy (on the recycled carrier after deposition, removal, and redeposition of the surface modification layer) due to the limited bonding area, thereby reusing the carrier. Can affect the potential. Also, the increased surface roughness may limit the reuse of the carrier in other applications, such as the use of the carrier itself as a display substrate, by not meeting the specifications for new glass roughness. It was also observed that after annealing the thin glass sheet and carrier bond pair at a temperature above 300 ° C., roughness was introduced on the bond 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 thin glass bonding surface with a fluorine-containing gas desorbed from the bonding surface of the surface modified layer treated support. In some cases, this increase in roughness of the binding surface is not necessary. In other cases, the increase in roughness is small, but this would be unacceptable as this increase may, for example, limit carrier reuse. Moreover, the use of fluorinated gases in certain manufacturing operations may have undesirable reasons, such as health and safety reasons.

Thus, it is strong enough to withstand controlled bonding, ie FPD processing, but it can still separate thin sheets from the carrier without damage (high temperature processing, eg at temperatures above 400 ° C. or above 600 ° C. In order to form a bond (even after processing), an alternative polar bond is used to provide sufficient surface energy (eg, greater than 50 mJ / m ² as discussed above with respect to the example in Table 5). It may be desirable to form. Accordingly, the inventors of the present application have studied alternative methods of forming suitable polar bonds that can be used to control and bond thin sheets to a carrier.

The inventors of the present application have studied the use of hydrocarbon polymers, or more generally carbonaceous layers, where little or no fluorine is utilized to etch glass. However, some important challenges had to be overcome. The surface energy of the carbonaceous layer must be greater than about 50 mJ / m ² for this carbonaceous layer to bond with the glass. In some cases, the carbonaceous surface modification layer has a surface energy of 65 mJ / m ² or more to provide a sufficiently strong bond between the thin sheet and the carrier 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 component of the hydrocarbon layer needs to be increased or mediated by hydrogen-bonded molecular water to achieve strong dipolar bonding directly with the silanol groups of the thin glass sheet. This carbonaceous layer is heat, chemical, and vacuum compatible so that it is useful for at least carrier / thin sheet articles that experience the manufacturing process of amorphous silicon (aSi) TFTs, color filters (CF), or capacitive touch devices. Sex should also be shown. This seemed possible because aliphatic hydrocarbons such as polyethylene exhibited great thermal stability in an inert atmosphere. Unlike fluoropolymers, which can depolymerize under certain circumstances, HDPE simply burns. HDPE may burn, but if the polymer thickness is small enough, it can still be seen there. The ultimate concern was that the mechanical stability and wet process suitability seemed 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 to withstand wet sonication on the thin sheet of glass used. This large binding energy is not due to the basic requirements of the bonding process, but to particles and edge defects. At best, bonding two clean glass surfaces can produce a binding energy of about 150 mJ / m ² . In order to achieve a bond strength of 250-275 mJ / m ² , some degree of covalent bonding is required.

The surface modified layers studied in the examples of Tables 6 to 12 are organic layers based on material sources that do not contain fluorine. 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 FPD processing. Not enough adhesion to the glass surface. This was not surprising since organic surface modification layers based on methane and hydrogen did not contain strong polar groups. In order to increase the polar groups available for bonding to the thin glass sheet, additional gas could be added during plasma polymerization to achieve sufficient surface energy (Table 7). However, in some cases, sufficient surface energy could be achieved, but this one-step process involves some degree of complexity in obtaining an appropriate mixture of material sources. Therefore, a two-stage process was developed: in the first stage, a surface modified 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 the thin glass sheet. Although there were many steps, this process was not so complex to somehow get the desired result. These treatments increase the polar groups on the surface of the surface modification layer that are bonded to the thin sheet. Thus, the interior of the surface modified layer may not contain polar groups in some cases, but polar groups can be used to bond the carbonaceous layer to a thin sheet. Various methods of treating the initial surface modified layer have been studied in the examples of Tables 8-12: In the example of Table 8, the surface modified layer is treated with 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 treated sequentially with N ₂ and then with H ₂ ; in the example of Table 11, the surface modified layer is Treated with N ₂ —O ₂ and then continuously with N ₂ ; in the example of Table 12, the surface modified layer is treated with N ₂ —O ₂ ; in the alternative example following Table 12, The surface modification layer is treated only with O ₂ . These examples show the use of nitrogen and oxygen polar groups, but other polar groups could be possible.

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

In the example of Table 6 below, a plasma polymerized film was deposited on a glass support using various conditions. The deposition parameters studied in the examples of Table 6 were: gas ratio (methane: hydrogen); pressure, ICP coil and RF bias power. The glass support was a substrate made from “Corning” “Eagle XG” (obtained 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 an Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK), an inductively coupled plasma (ICP) instrument. Here, the carrier is placed on the platen, to which a 13.56 MHz RF energy of a specific wattage (described in the “RF bias” column) is applied, a coil is placed on the platen, and Of 13.5 MHz RF energy was applied (in the "Coil" column). The flow rates of the methane (CH ₄ ) and hydrogen (H ₂ ) sources into the tank were as shown in the CH ₄ and H ₂ columns, respectively (flow rates were as per standard). Minute cubic centimeter-sccm). CH ₄ and H ₂ gases were flowed together. The “H ₂ / CH ₄ ” column also shows the ratio of H ₂ : CH ₄ feed gas, and the “Pressure” column also shows the tank pressure (millitorr). Thus, for example, the notation in Table 6 of Example 6a can be read as follows: In an Oxford ICP device, 6.7 sccm of CH ₄ and 33.3 sccm of H ₂ at a pressure of 20 millitorr (about 2.67 Pa). ); 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 similarly. The surface energies were measured in three different test liquids (in this case deionized water (shown in the “W” column), hexadecane (shown in the “H” column), and diiodomethane (“DIM”). Calculated in mJ / m ² (millijoule per square meter) by using the contact angle (CA)) and Wu model)). For surface energy, the polar (P) and dispersed (D) components and the total (T) are shown.

Examples surface energy related 6a~6j varied from about 40 to about 50 mJ / m ^2. In general, however, the surface energy of these examples was less than about 50 mJ / m ² (which is considered suitable for controllably bonding the glass carrier to a thin sheet of glass). The thickness of the surface modification 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 generate bubbles during the vacuum test and during the wet process test. It was observed that warm water penetration occurred.

  Although these surface modified layers themselves were not suitable for bonding to thin glass sheets, they were not suitable for other applications, such as electrons or other structures on thin polymer sheets, as described below. It may be used to apply a thin sheet of polymer to a glass carrier for processing. 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 electrons or other structures may be deposited, whereas the polymer portion forms a binding surface for controlled bonding with the glass carrier.

  In the example of Table 6, the bonding surface with the surface modification layer disposed thereon was glass, but this is not necessary. Alternatively, the bonding surface may be another suitable material having surface energy and properties similar to glass, such as silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

Another example of using a plasma polymerized film to adjust the surface energy of a surface modified layer with a mixture of non-fluorinated sources and to coat it with surface hydroxyl is a carbon-containing gas, for example, Deposition of a thin film of a surface modified layer from a mixture of non-fluorinated gas sources, including hydrocarbons. The surface modification layer may be deposited at atmospheric pressure or reduced pressure and may be performed by plasma excitation, eg, DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. Is called. The plasma polymerized surface modification layer may be deposited on a support, a thin sheet, or both. As described above with respect to the example of Table 3, plasma polymerization forms a layer of highly crosslinked material. Using reaction conditions and feed gas control, the thickness, density, and chemical properties of the surface modification layer can be controlled to tailor the desired application and control the film properties Thus, the surface energy of the binding surface can be adjusted. The surface energy controls the degree of bonding, i.e. during the subsequent processing performed to deposit a film or structure on the thin sheet, the permanent covalent bond between the thin sheet and the carrier. It can be adjusted to prevent.

In the example of Table 7 below, a plasma polymerized film was deposited on a glass support using various conditions. The glass support was a substrate made from “Corning” “Eagle XG” (obtained 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 an Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK) in an inductively coupled plasma (ICP) configuration mode. Here, the carrier is placed on the platen, to which a 13.56 MHz RF energy of a specific wattage (described in the “RF bias” column) is applied, a coil is placed on the platen, and Of 13.5 MHz RF energy was applied (in the "Coil" column). The flow rates of the methane (CH ₄ ), nitrogen (N ₂ ) and hydrogen (H ₂ ) feed gases into the tank were as shown in the CH ₄ , N ₂ and H ₂ columns, respectively. (The flow rate is cubic centimeter per minute-sccm under standard conditions). CH ₄ , N ₂ and H ₂ gas were flowed together. The “N ₂ / CH ₄ ” column also shows the ratio of N ₂ : CH ₄ feed gas, and the “Pressure” column also shows the tank pressure (millitorr). Thus, for example, the notation in Table 7 of Example 7g can be read as follows: In an Oxford 380 ICP device, 15.4 sccm CH ₄ , 3.8 sccm N ₂ and 30.8 sccm H ₂ are Flowed together in a 5 mTorr (approx. 0.67 Pa) bath; 1500 W of 13.5 MHz RF energy applied to the showerhead and 50 W of 13.56 MHz RF energy 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 similarly. The surface energies were measured in three different test liquids (in this case deionized water (shown in the “W” column), hexadecane (shown in the “H” column), and diiodomethane (“DIM”). Calculated in mJ / m ² (millijoule per square meter) by using the contact angle (CA)) and Wu model)). For surface energy, the polar (P) and dispersed (D) components and the total (T) are shown. Further, the “thickness” column 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 only from methane. Under these deposition conditions, the surface modification layer formed from methane achieved only about 44 mJ / m ² of surface energy on the support. This is not at the desired level for controlled bonding of glass to glass, but this may be useful for bonding polymer bonded surfaces to glass carriers.

Examples 7b to 7e show surface modification layers made from plasma polymerization of methane and nitrogen at various ratios of N ₂ : CH ₄ . Under these deposition conditions, a surface modification layer formed from methane and nitrogen achieved a surface energy on the support of about 61 mJ / m ² (Example 7e) to about 64 mJ / m ² (Example 7d). . These surface energies are sufficient to controllably bond 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, a surface modification layer made from methane and hydrogen achieved a surface energy of about 60 mJ / m ² on the support. This is sufficient to controllably bond 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, a surface modification layer made from methane, nitrogen and hydrogen has a surface energy of about 58 mJ / m ² (Example 7g) to about 67 mJ / m ² (Example 7j) on the support. Achieved. This is sufficient to controllably bond the thin glass sheet to the glass carrier.

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

  The thin glass sheets bonded to each of the supports, as in the examples in Table 7 (7b to 7j), are aluminoborosilicate alkali-free glass, “Corning” “Willow” Glass (Corning Incorporated, Corning, NY). Substrate having a thickness of 100, 130, and 150 micrometers. Prior to bonding, the “Willow” 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 with the surface modified layer disposed thereon was glass, but this is not necessary. Alternatively, the bonding surface may be another suitable material having surface energy and properties similar to glass, such as silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

The surface modified layer of the example of Table 7 is formed by a one-step process. That is, proper surface energy and polar group inclusion is achieved by depositing a surface modification layer from a selected mixture of gases under appropriate conditions. Although the proper gas and conditions have been achieved, the process involves some complexity to achieve the proper gas mixture. Therefore, a simpler process was sought. It was assumed that the appropriate surface energy and the appropriate polar group could be achieved from a two-step process where each step would be simple and stable. Specifically, in the first stage, a carbonaceous surface modification layer is deposited, while in the second stage, the surface modification layer is treated to increase the surface energy and provide the appropriate polarity for controlled bonding. It was assumed to generate a group. The polar groups will be more concentrated at the surface of the surface modification 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 power had the greatest effect on surface energy. It has also been found that the film thickness increases with increasing bias and decreasing pressure. Therefore, from these results, 20 sccm of CH ₄ with a carbonaceous surface modification layer of about 6.5 nm thickness was formed to further study the process to increase surface energy and include polar groups. A 40 sccm H ₂ , 5 millitorr (about 0.67 Pa), 1500/50 W and 60 second amorphous hydrocarbon polymer surface modification layer deposition process was selected as the starting point. In order to change the polar group and its concentration on the surface of the surface modification layer that bonds the thin sheet to this basic surface modification layer, various treatments were performed as described in the examples of Tables 8-11. Performed in two steps. Although specific examples of surface modifying layer starting materials and treatment materials are discussed below, in general, a carbonaceous layer is formed from a carbon-containing source and then polar groups are added by subsequent treatment. Similarly, specific polar groups are shown throughout the examples, but other polar groups could be possible.

Introduction of polar groups into the carbonaceous surface modification layer by NH ₃ treatment Another example of using a plasma polymerized film to adjust the surface energy of the binding surface and create an alternative polar group binding site thereon is as follows: 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. Nitrogen treatment may be performed, for example, by ammonia plasma treatment. The surface modification layer may be deposited by plasma excitation, eg, DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma, at atmospheric pressure or reduced pressure. . The plasma polymerized surface modification layer may be deposited on the support, thin sheet, or both. As described above for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Reaction conditions and feed gas control can be used to control the film thickness, density, and chemistry to tailor the functional group to the desired application. The surface energy can be adjusted. Nitrogen-based polar groups formed during the subsequent ammonia plasma treatment do not condense with silanol groups to form permanent covalent bonds, and therefore to deposit films or structures on thin sheets During subsequent processing, the degree of bonding between the thin sheet and the carrier can be controlled.

In the example of Table 8 below, various conditions were used to deposit a plasma polymerized surface modified layer film on a glass support. The glass support was a substrate made from “Corning” “Eagle XG” (obtained 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 an inductively coupled plasma (ICP) configuration mode. Here, the carrier is placed on the platen, to which a specific wattage of 13.56 MHz RF energy is applied, and a coil is placed on the platen, which has a specific wattage of 13.5 MHz RF energy. Was applied. More generally for 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 that of the coil. The gas flow rate into the vessel was as shown in Table 8 (flow rate is 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 Deposition” column of Table 8 for Example 8a can be read as follows: In an Oxford ICP device, in a vessel with a pressure of 5 millitorr (about 0.67 Pa), 40 sccm CH ₄ was flowed; 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; the bath temperature was 30 ° C. The deposition time was 60 seconds. The surface treatment column notation for the remaining examples can be read similarly, except that the surface treatment was performed within 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 “Plasma Treatment” column, the treatment notation in Example 8a can be read 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 with 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 treatment is carried out for 60 seconds. The “Plasma Processing” column notation for the remaining examples can be read similarly. The surface energy is calculated in mJ / m ² (per square meter) by using the contact angle and Wu model of three different test liquids, in this case deionized water (W), hexadecane (H), and diiodomethane (DIM). In millijoules). For surface energy, the polar (P) and dispersed (D) components and the total (T) are shown.

Examples 8a and 8b show plasma-modified hydrocarbon surface modification layers subsequently treated with a nitrogen-containing gas (ammonia). In Example 8a, ammonia was used alone at a power of 300 W, whereas in Example 8b, ammonia was diluted with helium and the polymerization was conducted at a lower power of 50 W. However, in each case, sufficient surface energy was achieved on the binding surface of the support and could be controllably bonded to a thin glass sheet. Examples 8c and 8d show plasma-modified hydrocarbon surface modification layers formed with hydrocarbon-containing (methane) and hydrogen-containing (H ₂ ) gases, followed by treatment with a nitrogen-containing gas (ammonia). ing. In Example 8c, ammonia was used alone at a power of 300 W, but in Example 8d, ammonia was diluted with helium and the polymerization was conducted at a lower power of 50 W. It was observed that the thin glass and support bonded by the surface modification layer formed as in Examples 8a-8d did not permanently adhere after annealing at 450 ° C., ie, 400 ° C. It was able to withstand item (c) of the temperature test. These samples were not tested for gas release. These examples are also 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 strength It remained peelable upon application. Exfoliation allows removal of devices made on thin glass and reuse of the carrier.

  The thin glass sheets bonded to each of the supports as in the examples in Table 8 are from “Corning” “Willow” Glass (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free glass. The produced substrates were 100, 130, and 150 micrometers thick. Prior to bonding, the “Willow” 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 with the surface modification layer disposed thereon was glass, but this is not necessary. Alternatively, the bonding surface may be another suitable material having surface energy and properties similar to glass, such as silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

Introduction of polar groups into the carbonaceous surface modification layer by N ₂ treatment Another example of using a plasma polymerized film to adjust the surface energy of the binding surface and create an alternative polar group binding site thereon is as follows: Deposition of a thin film of a surface modified layer from a carbon source (eg, a carbon-containing gas, such as methane) and from hydrogen H ₂ followed by nitrogen treatment of the just formed surface modified layer. Nitrogen treatment for forming nitrogen-based polar groups on the surface modification layer may be performed by plasma treatment with N ₂ gas. The surface modification layer may be deposited by plasma excitation, eg, DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma, at atmospheric pressure or reduced pressure. . The plasma polymerized surface modification layer may be deposited on the support, thin sheet, or both. As described above for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Using reaction conditions and feed gas control, the thickness, density, and chemical properties of the surface modification layer can be controlled to tailor the desired application and control the film properties Thus, the surface energy of the binding surface can be adjusted. Nitrogen-based polar groups formed during the subsequent plasma treatment do not condense with silanol groups to form permanent covalent bonds, and therefore to deposit films or structures on thin sheets During the subsequent processing that takes place, the degree of bonding between the thin sheet and the carrier can be controlled.

In the example of Table 9 below, various conditions were used to nitrogen treat the plasma polymerized film deposited on the glass support. The glass support was a substrate made from “Corning” “Eagle XG” (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to deposition of the surface modified 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 an inductively coupled plasma (ICP) configuration mode. Here, the carrier was placed on a platen, 50 W of 13.56 MHz energy was applied thereto, 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 poured into a tank having 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 deposition described above, the surface modified layer was treated with nitrogen. Specifically, during processing, a 13.56 MHz RF energy of a specific wattage (described in the “RF Bias” column) is applied to the platen, a coil is placed over the platen, and a specific wattage ( RF energy of 13.5 MHz (described in the “Coil” column) was applied. N ₂ was flowed into the vessel at a flow rate of 40 sccm over the time listed in this table (second (s)). Thus, for example, the notation of nitrogen treatment in Table 9 for Example 9a can be read as follows: In an Oxford ICP apparatus, 40 sccm of N ₂ is poured into a tank having a pressure of 5 millitorr (about 0.67 Pa). No; 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 with the carrier on top. The temperature was controlled at 30 ° C. and the treatment was carried out for 10 seconds. The notation for the remaining examples can be read similarly. The surface energies were measured for three different test liquids (in this case deionized water (shown in the “W” column), hexadecane (shown in the “HD” column), and diiodomethane (“DIM”). Calculated in mJ / m ² (millijoule per square meter) by using the contact angle (CA)) and Wu model)). For surface energy, the polar (P) and dispersed (D) components and the total (T) are shown.

Examples 9a-9j may use various conditions for nitrogen treatment of a surface modified layer formed with methane / hydrogen, thereby varying the surface energy suitable for bonding to a thin glass sheet, i.e. From 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 the plasma polymerization of methane and hydrogen). It was observed that the thin glass and support bonded by the surface modification layer formed as in Examples 9a-9j did not permanently adhere after annealing at 450 ° C., ie, 400 ° C. Pass the temperature test item (c). These samples were not tested for gas release. These examples are also 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 strength It remained peelable upon application. Exfoliation allows removal of devices made on thin glass and reuse of the carrier.

  The thin glass sheets bonded to each of the supports as in the examples in Table 9 are from “Corning” “Willow” Glass (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free glass. The produced substrates were 100, 130, and 150 micrometers thick. Prior to bonding, the “Willow” 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 with the surface modification layer disposed thereon was glass, but this is not necessary. Alternatively, the bonding surface may be another suitable material having surface energy and properties similar to glass, such as 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 the plasma polymerized film to adjust the surface energy of the binding surface and create alternative polar group binding sites thereon another example is a carbon source, for example, from methane (a carbon containing gas), and the deposition of a thin film of surface modification layer from the hydrogen H _2, followed by nitrogen surface modification layer just formed and then hydrogen It is a continuous process. The surface modification layer may be deposited under atmospheric pressure or reduced pressure by plasma excitation, eg, DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. Done. The plasma polymerized surface modification layer may be deposited on the support, thin sheet, or both. As described above for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Using reaction conditions and feed gas control, the thickness, density, and chemical properties of the surface modification layer can be controlled to tailor the desired application and control the film properties Thus, the surface energy of the binding surface can be adjusted. Nitrogen-based polar groups formed during the subsequent plasma treatment do not condense with silanol groups to form permanent covalent bonds, and therefore to deposit films or structures on thin sheets During the subsequent processing that takes place, the degree of bonding between the thin sheet and the carrier can be controlled.

In the example of Table 10 below, various conditions were used to treat (with nitrogen and subsequently hydrogen) the plasma polymerized film deposited on the glass support. The glass support was a substrate made from “Corning” “Eagle XG” (obtained 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 an inductively coupled plasma (ICP) configuration mode. Here, the carrier was placed on a platen, 50 W of 13.56 MHz energy was applied thereto, 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 poured into a tank having 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 modification layer was continuously treated with nitrogen and then with hydrogen. Specifically, in each case, for nitrogen treatment, 40 sccm of N ₂ was flowed through the tank, and 1500 W of 13.5 MHz RF energy was applied to the tank; the pressure of the tank was 5 millitorr (about 0.67 Pa). 50 W of 13.56 MHz RF energy was applied to the platen; the treatment was carried out for 60 seconds. Then, during hydrogen treatment, a 13.56 MHz RF energy of a specific wattage (listed in the “RF” column of Table 10) is applied to the platen, and a coil is placed over the platen, where the specific wattage is A number (described in the "Coil" column) of 13.5 MHz RF energy was applied. H ₂ was flowed into the vessel at a flow rate of 40 sccm over the time listed in this table (seconds (s)). Thus, for example, the notation of hydrogen treatment in Table 10 for Example 10a (performed after thin film deposition and its N ₂ treatment as described above) can be read as follows: In the Oxford ICP device, 40 sccm of H ₂ was flowed into a bath having a pressure of 20 millitorr (approx. 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 It was applied to the platen placed on top and the treatment was carried out for 15 seconds. The notation for the remaining examples can be read similarly. The surface energies were measured in three different test liquids (in this case deionized water (shown in the “W” column), hexadecane (shown in the “H” column), and diiodomethane (“DIM”). Calculated in mJ / m ² (millijoule per square meter) by using the contact angle (CA)) and Wu model)). For surface energy, the polar (P) and dispersed (D) components and the total (T) are shown.

A continuous plasma treatment of N ₂ and then H ₂ of the plasma polymerization surface modification layer formed from methane and hydrogen can be performed under a variety of conditions to achieve a variety of surface energies. As can be seen from Table 10, the surface energy varied from about 60 mJ / m ² (Example 10d) to about 64 mJ / m ² (Examples 10a, 10n, 10o, and 10p). This is suitable for bonding to thin glass sheets. It was observed that the thin glass and support bonded by the surface modification layer formed as in Examples 10a to 10p did not permanently adhere after annealing at 450 ° C., ie, 400 ° C. We were able to pass the item (c) of the temperature test. These examples are also 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 strength It remained peelable upon application. Exfoliation allows removal of devices made on thin glass and reuse of the carrier.

  Thin glass sheets bonded to each of the supports as in the example of Table 10 are from “Corning” “Willow” Glass (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free glass. The produced substrates were 100, 130, and 150 micrometers thick. Prior to bonding, the “Willow” 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 with the surface modification layer disposed thereon was glass, but this is not necessary. Alternatively, the bonding surface may be another suitable material having surface energy and properties similar to glass, such as silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

As a modification of the example in Table 10, nitrogen and the subsequent hydrogen treatment were also performed on the surface modification layer formed from methane. In this case, when the first surface modification layer was formed on the glass support by plasma polymerization, methane was used alone (without hydrogen). Specifically, 40 sccm of methane was allowed to flow at a pressure of 5 mTorr (about 0.67 Pa) at an output of 1500/50 W for 60 seconds. Its surface energy was measured to be about 42 mJ / m ² . Nitrogen (5 mTorr (about 0.67 Pa) pressure for 15 seconds, 40 sccm N ₂ at 1500/50 W output), then hydrogen (5 mTorr (about 0.67 Pa) for 15 seconds) The surface energy achieved on the support surface of the support during continuous treatment with pressure, 1500/50 W output, 40 sccm H ₂ ) is about 64 mJ, suitable for binding a thin glass sheet to a glass support. / M ² increased.

The N ₂ and H ₂ continuous treatment of the carbonaceous surface modified layer, as described above, achieves a surface energy of about 64 mJ / m ² and is slightly slower than the bond front speed typical for fluorinated surface modified layers. At a rate, an initial room temperature bond is formed on a thin glass sheet. With respect to the examples in Table 10, these samples were observed to not permanently adhere after annealing at 450 ° C., ie they may pass item (c) of the 400 ° C. temperature test. did it. These examples are also 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 strength It remained peelable upon application. Exfoliation allows removal of devices made on thin glass and reuse of the carrier.

Based on the idea to create more polar imide groups on the surface of the introduction of polar groups into the carbonaceous surface modified layer by continuous treatment of N ₂ —O _{2 and} then N ₂ to increase the binding front speed, 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 tune the surface energy of the binding surface and create an alternative polar group binding site thereon includes carbon sources such as carbon-containing gases (eg methane) and hydrogen H the deposition of a thin film of a carbonaceous surface modification layer from _2, followed by a continuous treatment of N ₂ -O ₂ then N ₂ surface modification layer just formed. The surface modification layer may be deposited by plasma excitation, eg, DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma, at atmospheric pressure or reduced pressure. . The plasma polymerized surface modification layer may be deposited on the support, thin sheet, or both. As described above for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Using reaction conditions and feed gas control, the thickness, density, and chemical properties of the surface modification layer can be controlled to tailor the desired application and control the film properties Thus, the surface energy of the binding surface can be adjusted. Nitrogen-based polar groups formed during the subsequent plasma treatment do not condense with silanol groups to form permanent covalent bonds, and therefore to deposit films or structures on thin sheets During the subsequent processing that takes place, the degree of bonding between the thin sheet and the carrier can be controlled.

  In the example of Table 11 below, various conditions were used to treat the plasma polymerized film deposited on the glass support to increase the surface energy and include polar groups. The glass support was a substrate made from “Corning” “Eagle XG” (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free display glass. Prior to deposition of the surface modified 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 an inductively coupled plasma (ICP) configuration mode. Here, the carrier was placed on a platen, 50 W of 13.56 MHz energy was applied thereto, 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 poured into a tank having 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 of 13.56 MHz RF energy was applied to the platen, a coil was placed on the platen, and 800 W of 13.5 MHz RF energy was applied thereto. . N ₂ and O ₂ were flowed into the vessel at the specified flow rate (sccm) for the time listed in this table (seconds (s)). Thus, for example, for Example 11a, the notation of step 2 in Table 11 can be read as follows: After deposition of the surface modified layer in step 1, 35 sccm N ₂ is added to the 5 sccm O _{2 in the} Oxford ICP apparatus. With a pressure of 15 millitorr (approx. 2.0 Pa); 800 W of 13.5 MHz RF energy applied to the showerhead; 50 W of 13.56 MHz RF energy placed on the carrier Applied to the platen, the carrier was temperature controlled at 30 ° C. and the treatment was carried out for 5 seconds. The notation for the remaining examples can be read similarly.

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 of 13.56 MHz RF energy was applied to the platen, a coil was placed on the platen, and 1500 W of 13.5 MHz RF energy was applied thereto. . N ₂ was flowed into the vessel at the specified flow rate (sccm) over the time listed in this table (seconds (s)). Thus, for example, for Example 11a, the notation of step 3 in Table 11 can be read as follows: After deposition of the surface modified layer in step 1, after the nitrogen-oxygen treatment in step 2, the Oxford ICP device At 40 sccm of N ₂ was poured into a bath having a pressure of 5 millitorr (approx. 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 the platen placed above, the carrier was temperature controlled at 30 ° C., and the treatment was carried out for 15 seconds. The notation for the remaining examples can be read similarly.

Surface energy is calculated in mJ / m ² (millijoule 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 energy, the sum (including T, both polar and dispersive components) is shown. The binding energy was calculated as mJ / m ² as described above. The number of bubbles after the first bond is shown in the column entitled “23 C area%”, while the number of bubbles after the 400 ° C. temperature test is shown in the column entitled “400 C area%”. The number of bubbles was determined by an optical scanner as described below for “gas release”. Finally, the change in bubble area from the first at 23 ° C. to after the 400 ° C. temperature test is shown in the column entitled “Difference Area%”.

Examples 11a-11e may use various conditions for continuous treatment of nitrogen-oxygen, then nitrogen, of a surface modified layer formed by methane / hydrogen, thereby making it suitable for bonding to thin glass sheets. A variety of surface energies suitable for bonding to thin glass sheets, ie from about 65 mJ / m ² (Examples 11a and 11e) to about 70 mJ / m ² (Examples 11b and 11d) may be obtained. Show. These surface energies obtained after continuous treatment of nitrogen-oxygen and then nitrogen increased from about 40-50 mJ / m ² (obtained from the base layer formed from the plasma polymerization of methane and hydrogen). It was observed that the thin glass and support bonded by the surface modification layer formed as in Examples 11a-11f did not permanently adhere after annealing at 400 ° C., that is, they were 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, step 3 is important so that the surface modified layer deposited according to the conditions in Table 11 does not emit gas. However, under other deposition / processing conditions for steps 1 and 2, step 3 would not need to obtain the same outgassing results as obtained by step 3 for examples 11a-e. These examples are also powerful enough to withstand FPD processing (including the vacuum test (1), wet process test (2), and ultrasonic test (5) described above) and after the 400 ° C. temperature test The film remained peelable when a sufficient peeling force was applied. Exfoliation allows removal of devices made on thin glass and reuse of the carrier.

The effects of these continuous processes 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) gave 69 mJ / d during the 400 ° C. temperature test. A surface energy of m ² and a bubble area of 1.2% result (change in bubble area% from 23 ° C. is −0.01, indicating no outgassing). The performance of Examples 11a-e is comparable to fluorinated surface modified layers in applications up to 400 ° C. temperature test.

  The thin glass sheets bonded to each of the supports as in the examples in Table 11 are from “Corning” “Willow” Glass (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free glass. The produced substrates were 100, 130, and 150 micrometers thick. Prior to bonding, the “Willow” 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 with the surface modification layer disposed thereon was glass, but this is not necessary. Alternatively, the bonding surface may be another suitable material having surface energy and properties similar to glass, such as 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 support for device processing. Illustrates what can be done. However, the scalability of this solution for display applications (large area substrates are advantageous) is a concern. ICP equipment utilizes planar, cylindrical, or hemispherical coils to inductively couple current to create a time-dependent magnetic field that circulates ions. A second RF source is typically connected to the platen on which the substrate rests. An advantage of the 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. TEL and others have expanded the ICP etching apparatus to the fifth generation, but it is difficult to expand the ICP etching apparatus 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 similar results in the RIE mode process to those achieved by ICP equipment as described above.

  Simply use the Oxford device with the RIE mode (no coil power) and 200 W bias power (equivalent to that used to deposit the fluorinated surface modification layer) from the non-fluorinated feed to RIE mode surface modification. The first attempt to produce a quality layer resulted in a darker thick layer that could be nitrogen modified and bonded to a thin glass sheet. However, this dark material produced many bubbles that covered about 25% of the bonded area after undergoing a 400 ° C. treatment test. Characterization of this dark deposit by spectroscopic ellipsometry indicates that the film thickness is about 100 nm, with a much narrower optical band gap compared to 1.7 eV for the ICP deposited surface modification layer 0.6 eV was indicated. 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 generation.

To map RIE process variables, H ₂ / CH ₄ ratio, RF power, and pressure, experiments were performed to obtain emission spectroscopy (OES) spectra. 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 OES leading to process conversion from ICP mode to RIE mode, residual gas is used to map the gas phase species present in the Oxford instrument as a function of hydrogen / methane ratio, RF power, and pressure in RIE mode. Analysis (RGA) was used. Contour plots of m / e = / 16 to pressure and H ₂ / CH ₄ gas ratio again showed that high hydrogen dilution is beneficial to meet an ICP ratio of about 44. Higher alkanes correlate with decreased H ₂ / CH ₄ gas ratio and increased pressure. This contour plot shows m / e = 28/16 increasing with both RF and H ₂ / CH ₄ gas ratios. The fitting of the RGA response surface is such that the H ₂ / CH ₄ ratio and the C ₂ H ₆ / CH ₄ ratio are matched at 40: 1 H ₂ / CH ₄ , 25 millitorr (about 3.3 Pa), 275 W RF Suggesting that. The carbonaceous RIE mode surface modification layer deposited under this condition was consistent with the ICP mode carbonaceous surface modification 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 modified layer also showed less bubble generation.

  The kinetics of RIE mode carbonaceous surface modification layer deposition using the process specified by this RGA experiment are shown in FIGS. Surface energy, including total (T) and polar (P) and dispersion (D) components, is shown in FIG. It can be seen that the deposition time of 60 seconds has a slight peak and the surface energy is relatively unchanged, while in FIG. 15, 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 turns out that. 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 be tolerated, 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.

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

In the example of Table 12 below, various conditions were used to deposit a plasma polymerized surface modified layer film on a glass support. The glass support was a substrate made from “Corning” “Eagle XG” (obtained 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 RIE configuration mode, Oxford Plasmalab 380 ICP (obtained from Oxford Instruments, Oxfordshire, UK). Here, the carrier was placed on the platen, 275 W of RF energy was applied to it, and a coil was placed on the platen, and no energy was applied thereto. In step 1, 2 sccm of methane (CH ₄ ) and 38 sccm of hydrogen (H ₂ ) were poured into a tank having a pressure of 25 millitorr (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 modification layer was treated with nitrogen and oxygen. Specifically, during the process of Step 2, a 13.56 MHz RF energy of a specific wattage (described in the “RF” column) is applied to the platen, and a coil is placed on the platen, where the energy is Was not applied. Over the time (seconds) listed in the “Time (s)” column of this table, N ₂ was allowed to flow into the vessel at the flow rate of sccm listed in the “N2” column, and O ₂ was flown through. The flow rate was sccm listed in the column of “O 2”, and was flowed into the tank. The tank was at a pressure expressed in millitorr, as listed in the “Pr” column. Thus, for example, for Example 12b, the notation for nitrogen and oxygen treatment in Step 2 in Table 12 can be read as follows: In an Oxford ICP apparatus, 25 sccm N ₂ with 25 sccm O ₂ and a pressure of 10 millitorr (About 1.3 Pa) was poured into the tank; 300 W of 13.56 MHz RF energy was applied to the platen with the carrier on top, the carrier was temperature controlled to 30 ° C., and the treatment was performed for 10 seconds. I went there. The notation for the remaining examples can be read similarly.

The surface energy is calculated in mJ / m ² (per square meter) by using the contact angle and Wu model of three different test liquids (in this case deionized water (W), hexadecane (HD), and diiodomethane (DIM)). In millijoules). For surface energy, the polar (P) and dispersed (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 bubble area% change (bubble area after first bonding a thin glass sheet to the support through the surface modification layer at room temperature and the 400 ° C. process. The test also shows “Δ bubble%” between the bubble area after heating the support).

  Thin glass sheets bonded to each of the supports as in the examples in Table 12 are from “Corning” “Willow” Glass (obtained from Corning Incorporated, Corning, NY), which is an aluminoborosilicate alkali-free glass. The manufactured substrates were 100, 130, and 150 micrometers thick. Prior to bonding, the “Willow” 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 with the surface modification layer disposed thereon was glass, but this is not necessary. Alternatively, the bonding surface may be another suitable material having surface energy and properties similar to glass, such as silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

  From the treatment in the example of Table 12, after treatment at 400 ° C .: All of Examples 12a to 12j show a change in percent bubble area of less than 2, which is consistent with no outgassing at this temperature (Table And the samples 12a, 12b, 12c, 12g, and 12j each had a binding energy that was capable of peeling from the thin sheet carrier after this temperature test (Table 1). Example 12d, 12e, 12f, 12h, and 12i could not be peeled after 400 ° C. process testing, as indicated by the 2500 values 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 decrease in thickness correlates with increasing RF power (comparing Example 12g with Example 12b) and% O2 (Comparing Example 12a with Example 12b), which is consistent with the ashing of the hydrocarbon layer. . The binding energy depended only on the pressure: the sample treated at 10 mTorr (about 1.3 Pa) was able to peel after annealing at 400 ° C. (see Examples 12a, 12b, 12c, 12g). What processed at 35 millitorr (about 4.7 Pa) or more was not made. See, for example, Example 12d having a binding energy of 2500 treated at 40 millitorr (about 5.3 Pa) and Example 12e having a pressure of 70 millitorr (about 9.3 Pa) and a binding energy of 2500. The 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 regardless of thickness. See Examples 12a through 12i and 12k. These results suggest that a discontinuous film is formed by the high-pressure N ₂ —O ₂ plasma treatment. In fact, the high pressure removes the membrane rapidly, so that the low pressure is beneficial. With respect to bubble generation, the amount appeared to decrease as% O2 * RF increased. Furthermore, 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 Δ bubble% increases. Increases with pressure (thus lower pressure is beneficial during step 2); as the processing time increases, the thickness of the surface modified layer decreases, as well as the polar groups decrease and therefore more It turns out that a short processing time is beneficial.

The appropriate binding energy and bubble generation balance was determined. The starting point for the nitrogen-oxygen treatment was 50% O ₂ , 10 mtorr (about 1.3 Pa), 300 W and various treatment times. Three sets of samples were prepared by RIE CH ₄ —H ₂ deposition at 20 seconds, 60 seconds and 180 seconds, followed by 0, 5, 15 and 60 seconds 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. The thin 20 second CH ₄ —H ₂ layer is removed and the thin glass sheet is permanently bonded to the carrier. A peak occurs before the polymer layer is removed, 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. Surface modification layer deposition time (not too long as it will lead to greater thickness resulting in increased outgassing) and N ₂ —O ₂ treatment time (—removing or removing the surface modification layer ( It is based on balancing with (not long enough to provide a permanent bond to a thin sheet of support) 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. In order to study and confirm the speciation of these surface modification layers, they were deposited on an “Eagle XG” glass wafer to completely cover the glass, followed by N ₂ / O ₂ plasma for various periods of time. The surface chemistry of the treated, CH ₄ / H ₂ relatively thick film was studied. The advantage of a thick hydrocarbon film is that it can identify nitrogen species that occur only on the hydrocarbon film and distinguish them from those that occur on the exposed glass.

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

Exposure of this carbonaceous film to 60 and 600 seconds of N ₂ / O ₂ plasma 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 treatments of 60 seconds and 600 seconds, the C concentration is less than 10 at%, which strongly suggests that in those cases the surface is partially covered by the carbonaceous layer.

NH ₃ ⁺ species are detected only when a substantial amount of the carbonaceous film is removed by etching. This suggests very strongly that the NH ₃ ⁺ species appear to be present only on the glass, and that other species mainly include reactions 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 effect of this N ₂ —O ₂ treatment is 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. Another observation is the presence of nitrogen species on the surface modified layer even after very short N ₂ —O ₂ treatment times, eg 5 and 15 seconds. The nitrogen species then decreases rapidly, while the ammonia species (indicating the presence of the underlying glass surface) increases rapidly. 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 It was. The presence of the oxygen-containing species leads to the idea that only O ₂ plasma would be sufficient to give the surface modified layer polar groups. In fact, this turns out to be so 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 only occur on the glass and not on the carbonaceous layer Can do. The result of estimation of this surface coverage is given in FIG. There is almost no change between 5 and 15 seconds. The biggest change appears between 15 and 60 seconds of N ₂ -O ₂ plasma treatment time.

Model N ₂ -O ₂ plasma treatment of the carbonaceous surface modification layer is as follows. The CH ₄ —H ₂ deposition results in a continuous hydrocarbon layer. In the first few seconds of the N ₂ —O ₂ plasma treatment, the hydrocarbon layer is oxidized and ablated so that polar —NH ₂ groups are formed on the polymer surface. Imido or amide groups may also be formed at this time, but their XPS is indeterminate. As the N ₂ —O ₂ plasma treatment is lengthened, polymer removal reaches the glass surface, where polar —NH ₃ ⁺ groups are formed from the interaction between the N ₂ —O ₂ plasma and the glass surface.

Single O ₂ as surface treatment for surface modification 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 noted above, XPS carbon speciation of the carbonaceous layer with a 5 second N ₂ —O ₂ plasma treatment indicated that the oxygen-containing species was actually present on the surface modified layer. Therefore, an O ₂ treatment of the carbonaceous layer was attempted. O ₂ treatment was performed in both ICP mode and RIE mode.

In the ICP mode, a basic carbonaceous layer was formed as in Step 1 of Table 11 above. Next, the surface treatment of Step 2 is 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 millitorr (about 2.0 Pa). The desired polar group was generated on the surface of the carbonaceous layer. The thin glass sheet was easily bonded to the surface modification layer at room temperature. It was also observed that this sample did not permanently bond after annealing at 450 ° C., ie, this sample was able to pass item (c) of the 400 ° C. treatment 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 upon application of sufficient peel force Remained possible. Exfoliation allows removal of devices made on thin glass and reuse of the carrier.

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

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

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

The change of surface roughness of the bonding surface of glass due to the deposition of surface modification layer formed with surface roughness hydrocarbons was studied. Specifically, a surface modification layer formed from nitrogen and then methane-hydrogen treated with hydrogen was selected. A surface modification layer is formed from methane-hydrogen, followed by continuous in situ N ₂ and then H ₂ plasma treatment (60 CH, ₄₀ CH ₂ 5 mTorr (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 modified layer of the first support (Example 14a) was removed by O ₂ plasma cleaning followed by SC1 cleaning. The surface modified layer of the second support (Example 14b) was left in place. The third support (Example 14c) was used as a reference and was not provided with a surface modification layer. Using AFM, apply the surface modification layer and then determine the surface roughness of the removed carrier (Example 14a), the carrier still having the surface modification layer on it (Example 14b), and the reference carrier (Example 14c). 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. Note that for Example 14c, the excess z-range in the 5 × 5 micron scan was due to particles in the scanned area. Thus, it turns out that the surface modification layer formed with the hydrocarbon of this indication does not change the surface roughness of the bonding surface of glass. In certain circumstances, a constant surface roughness of the binding surface may be beneficial, for example, for carrier recycling. The glass support in these examples was a substrate made from “Corning” and “Eagle XG” (obtained 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 is at room temperature without any additional heat or chemical energy to change the bonding interface between the thin sheet and the carrier. Done. The only energy input is mechanical traction and / or peel force.

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

  Where both the thin sheet and the carrier have a glass bonding surface, the surface modification layer described above in Examples 3 to 12 can be applied to 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 binding surface is a glass binding surface (as described further below), the suitable 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 different layers and / or within it as long as the binding surface is suitable to receive the surface modification layer of interest. Materials 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 the thin sheet 20 can be of any suitable material including, for example, silicon, polysilicon, single crystal silicon, sapphire, quartz, glass, ceramic, or glass ceramic. For example, the binding surface of the 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 herein, the surface modification layer, along with subsequent processing, provides a way to widely vary the surface energy on the bonding surface of the glass. For example, it can be seen from all of the previous examples 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). If a non-fluorinated surface material is used in a one-step process without subsequent surface treatment, the surface energy of the bonded surface of the glass is from about 37 mJ / m ² (Example 16b) to about 67 mJ / m ² (Example It can be seen that from 7h to 7j) can be changed. Using a carbonaceous surface modification layer with subsequent treatment to increase polar groups, the surface energy of the bonded surface of the glass is 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 either 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). It can be seen that it can be changed. With the subsequent treatment, using either a fluorine-containing or non-fluorine-containing feed to deposit the surface modification layer, the surface energy of the bonded surface of the glass is about 41 mJ / m ² (Example 5m ) To about 80 mJ / m ² (Example 5f).

  Moreover, as can be seen from the examples described here, the thickness of the surface modification layer can vary widely. Desirable results were 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 support surface modification layers (including heat treatment of materials and associated bonding surfaces) is a process that requires temperatures above 600 ° C., such as in LTPS processing, for example. It is to provide carrier recycling in articles that experience the above. Using surface modification layers (including heat treatment of materials and bonded surfaces), as exemplified by the previous examples 2e, 3a, 3b, 4c, 4d, and 4e, and the examples in Table 5, such Support recycling may be provided under temperature conditions. Specifically, these surface modification layers are used to change the surface energy of the overlapping area between the bonding areas of the thin sheet (having the glass bonding surface) and the carrier (having the glass bonding surface), thereby After processing, the entire thin sheet may be separated from the carrier. This thin sheet can be separated all at once or, for example, when the device fabricated on the thin sheet part is first removed, it is partly separated and then the remaining part is removed and 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 prepared once more to carry a thin sheet by washing and forming a surface modifying layer once again. The surface modification layer prevents permanent bonding with the thin sheet carrier and can therefore be used in processes where the temperature is 600 ° C. or higher. Of course, these surface modified layers will control the energy of the binding surface during processing at temperatures above 600 ° C., but produce a thin sheet and carrier combination that will withstand processing at lower temperatures. And may be used for such lower temperature applications to control bonding. Furthermore, if the thermal processing of the article does not exceed 400 ° C., examples 2c, 2d, 4b, and examples in Tables 7-11 (including examples 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 layers described herein, for example, examples in Table 3, Examples 4b, 4c, 4d, 4e, Examples in Tables 5 and 7-11, Examples 12a, 12b, 12c, 12g, 12j, and O ₂ only One of the advantages of using a surface modification layer, including the example of surface treatment by is that the support can be reused in the same size. That is, the thin sheet is removed from the carrier, the surface modification 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 surface modification layers (including heat treatment of materials and associated bonding surfaces) is controlled between the glass carrier and a thin sheet of glass. Is to provide a combined area. More particularly, by using a surface modification layer, a zone of controlled bonding can be formed, where there is no damage to either the thin sheet or the carrier caused by the bonding and there is sufficient separation force. The thin sheet portion can be separated from the carrier, yet a sufficient bonding force to hold the thin sheet against the carrier is maintained throughout processing. Referring to FIG. 6, a thin glass sheet 20 may be bonded to the glass carrier 10 by a bonding area 40. In the bonding zone 40, the carrier 10 and the thin sheet 20 are covalently bonded to each other so that they act as a monolith. In addition, there is a controlled bonding area 50 having a perimeter 52, where the carrier 10 and the thin sheet 20 are connected, but even after high temperature processing, for example processing at temperatures 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. Examples 2a, 2e, 3a, 3b, 4c, 4d, and 4e, using a surface modification layer 30 that includes heat treatment of the material and the bonding surface, as illustrated by the examples in Table 5, 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. Specifically, these surface modification layers may be formed within the periphery 52 of the controlled bonding area 50 either on the carrier 10 or on the thin sheet 20. Thus, if article 2 is processed at high temperature, either to form a covalent bond in bonding area 40 or during device processing, carrier 10 and thin sheet 20 are within the area surrounded by perimeter 52. A controlled bond can be provided between them so that the separation force (without catastrophic damage to the thin sheet or carrier) will separate the thin sheet and carrier in this region, 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 concept of support in US Pat. In particular, the carriers of US Pat. No. 6,057,059 have been shown to withstand FPD processing including high temperature processing above about 600 ° C. with respect to their bonded peripheral and unbonded central regions, but ultrasonic processes such as wet Cleaning and resist removal processing remained a challenge. Specifically, since there was little or no adhesive force to bond the thin glass and the carrier in the non-bonded region, pressure waves in the solution caused the non-bonded region (non-bonding was described in Patent Document 1). It was found to introduce resonance into thin glass. Standing waves can be formed in thin glass, where these waves break the thin glass at the interface between the bonded and unbonded regions if the ultrasonic agitation is of sufficient strength May cause vibration. The problem is to minimize the gap between the thin glass and the carrier and to provide sufficient adhesion or controlled bonding between the carrier 20 and the thin glass 10 in these areas 50. Can be eliminated. The surface modification layer (including materials and any associated heat treatment) of the binding surface as illustrated by examples 2a, 2e, 3a, 3b, 4c, 4d, 4e, and the examples in Table 5 was controlled. In order to avoid these undesirable vibrations in the bonding region, the binding energy is controlled to provide sufficient bonding between the glass bonding surface on the thin sheet 20 and the glass surface on the carrier 10.

Then, during the harvesting of the desired portion 56 having the perimeter 57, the portion of the thin sheet 20 within the perimeter 52 is easily separated from the carrier 10 after processing and after separation of the thin sheet along the perimeter 57. Let's go. Since 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 600 ° C. or higher. Of course, these surface modified layers will control the binding surface energy during processing at temperatures above 600 ° C., but they will combine a thin sheet and carrier combination that will withstand processing at lower temperatures. It may also be used for manufacturing and may be used for such lower temperature applications. Further, if the thermal processing of the article does not exceed 400 ° C., examples 2c, 2d, 4b, examples in Tables 7-11 (including examples discussed as alternatives to the examples in Table 10), examples 12a, 12b, 12c 12g, 12g, as well as the surface modification layer illustrated by the example of surface treatment with only O ₂ —depending on other process requirements—in some cases—also used to control the binding surface energy. May be.

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

  In one embodiment of the third use, the bonding section 40, the carrier 10 and the thin sheet 20 may be covalently bonded together so that they act as a monolith. In addition, there is a controlled bonding area 50 having a perimeter 52, where the carrier 10 and the thin sheet 20 are sufficiently bonded together to withstand processing and still be hot processed, e.g. It is possible to separate the thin sheet from the carrier even after processing at this temperature. Thus, the surface modification layer 30 (material and bonded surface heat treatment, as exemplified by 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. Specifically, these surface modification layers and heat treatments 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 a high temperature or is processed at a high temperature to form a covalent bond, the carrier and the thin sheet 20 are within the bonding area 40 outside the area surrounded by the perimeter 52. Join each other. Then, if it is desired to dice the thin sheet 20 and carrier 10 during harvesting of the desired portion 56 having a perimeter 57, these surface modification layers and heat treatments cause the thin sheet 20 and carrier 10 to monolith in this area. The thin sheet 20 and the carrier 10 may be separated along line 5 because they are covalently bonded to act as. Since the surface modification layers provide permanent covalent bonds with the thin sheet carrier, they may be used in processes where the temperature is 600 ° C. or higher. Further, if the thermal processing of the article, or the initial formation of the bonding zone 40 is above 400 ° C. but below 600 ° C., the same surface modified layer as exemplified by the material and heat treatment in Example 4a May be used as well.

In the 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 controlled bonding through the various surface modification layers described above. In addition, there is a controlled bonding area 50 having a perimeter 52, where the carrier 10 and the thin sheet 20 are sufficiently bonded together to withstand the processing, and still remain at high temperature processing, eg 600 ° C. Even after processing at these temperatures, a thin sheet can be separated from the carrier. Thus, if processing is performed at temperatures up to 600 ° C. and it is desirable that the zone 40 does not have permanent or covalent bonds, the previous examples 2e, 3a, 3b, 4c, 4d, 4e, and Table 5 Using a surface modification layer 30 (including heat treatment of the material and bonding surface) as illustrated by way of example, a bonding area 40 between the glass bonding surface of the carrier 10 and the glass bonding surface of the thin sheet 20. May be provided. Specifically, these surface modification layers and heat treatments 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 of the same or different surface modification layer formed in the bonding area 40. Alternatively, if processing is only performed at temperatures up to 400 ° C. and it is desired that the zone 40 has no permanent or covalent bonds, the previous examples 2c, 2d, 2e, 3a, 3b, 4b, 4c, Surface treatment with 4d, 4e, examples in Table 5, examples in Tables 7-11 (including examples discussed as alternatives to examples in Table 10), examples 12a, 12b, 12c, 12g, 12g, and O ₂ only Using a surface modification layer 30 (including heat treatment of the material and the bonding surface) as illustrated by the example of FIG. 1, the bonding area between the glass bonding surface of the carrier 10 and the glass bonding surface of the thin sheet 20 40 may be provided.

  Instead of controlled bonding in area 50, there may be an unbonded area in area 50, where the unbonded area is an area with increased surface roughness as described in US Pat. Or may be provided by a surface modified 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 laminate of glass sheets. Annealing is a thermal process to achieve glass consolidation. 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 prior to processing rather than during subsequent processing. Subsequent pre-processing anneals, such as in the manufacture of flat panel display devices, require that structures manufactured from many layers be aligned with very stringent accuracy 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 layer of structure deposited on the glass prior to the high temperature process may not align exactly with the layer of structure deposited after the high temperature process.

  It is economically attractive to consolidate glass sheets in a laminate. However, this makes it necessary to sandwich something between adjacent sheets or to separate them to avoid sticking. At the same time, it is beneficial to keep the sheets very flat and optical quality, or a clean surface finish. Moreover, for certain laminates of glass sheets, eg, low surface area sheets, the glass sheets “stick” to each other during the annealing process so that the glass sheets can be moved easily 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 to each other at the same time as other sheets of glass sheets, or portions of those other glass sheets, eg, their peripheries are permanently attached to each other. It may be beneficial to anneal a laminate of glass sheets that are bonded together. As yet another alternative, it may be beneficial to laminate glass sheets so that the perimeters of selected adjacent pairs of sheets in the laminate are selectively and permanently bonded together. The bulk annealing and / or selective bonding described above will be achieved using the above-described manner of controlling the bonding between the glass sheets. In order 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 laminate of glass sheets suitable for bulk annealing or bulk permanent bonding in selected areas (eg, around) 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 comprise a glass sheet 770-772 and a surface modification layer 790 for controlling the bonding between the glass sheets 770-772. In addition, the laminate 760 may include cover sheets 780 and 781 disposed on the top and bottom of the laminate, and may include a surface modification layer 790 between the cover and the 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, such as aluminosilicate glass, borosilicate glass, or aluminoborosilicate glass. In addition, the glass may contain alkali or be non-alkali. Each of the glass sheets 770 to 772 may have the same composition, or the sheets may have different compositions. Furthermore, the glass sheet may be of any suitable type. That is, for example, all of the glass sheets 770 to 772 may be a carrier as described above, may be a thin sheet as described above, or may be a carrier and a thin sheet alternately. If the bulk anneal requires a different time-temperature cycle for the support than the thin sheet, it is beneficial to have a stack of support and a separate stack of thin sheets. Alternatively, with proper surface modification layer material and placement, it has alternating carrier and thin sheet stacks so that the desired pair of carrier and thin sheet, i.e. the pair forming the article, is later It would be desirable to maintain the ability to separate adjacent articles from each other while 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 the laminate 760.

  In any particular laminate 760, any one glass sheet may have one surface modified layer that does not have a surface modified layer, or two surface modified layers. For example, as shown in FIG. 8, the sheet 770 does not have a surface modification layer, the sheet 771 has one surface modification layer on the second major surface 778, and the sheet 772 has one surface modification layer. There are two surface modification layers 790 so that the quality layer is on each of the major surfaces 776, 778.

  The cover sheets 780, 781 can be any material that will properly withstand the time-temperature cycle for a given process (not only with respect to time and temperature, but also with other relevant considerations such as outgassing, for example). May be. It may be convenient for the cover sheet to be made from the same material as the glass sheet being processed. If the cover sheets 780 and 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 A surface modification layer 790 may be provided between the glass sheet 772 and the cover sheet 780. If a surface modification layer is present between the cover and the glass sheet, even on the cover (as shown for cover 781 and adjacent sheet 771), on the glass sheet (cover 780 and adjacent sheet 772). Or as shown (not shown) on both the cover and the adjacent sheet. Alternatively, if the cover sheets 780, 781 are present but of a material that does not bond to the adjacent sheets 772, 771, then the surface modification layer 790 need not be between them.

  There is an interface between adjacent sheets in the laminate. For example, an interface is defined between adjacent glass sheets 770-772, that is, there is an interface 791 between the sheet 770 and the sheet 771, and an interface 792 between the sheet 770 and the sheet 772. In addition, when the cover sheets 780 and 781 exist, 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.

  In order to control bonding at a predetermined interface 791, 792 between adjacent glass sheets or at a predetermined interface 793, 794 between a glass sheet and a cover sheet, the surface modification layer 790 is used. Also good. For example, as shown in the figure, a surface modification layer 790 is present on each of the interfaces 791 and 792 on at least one of the main surfaces facing the interface. For example, for the interface 791, the second major surface 778 of the glass sheet 771 is provided with a surface modification layer 790 to control the bond between the sheet 771 and the adjacent sheet 770. Although not shown, the first major surface 776 of the sheet 770 may also include a surface modification layer 790 thereon to control bonding with the sheet 771, ie, any particular interface. There may be a surface modification layer on each of the major surfaces facing the surface.

  A particular surface modification layer 790 at any given interface 791-794 (and any associated surface modification treatment--e.g., Heat treatment to that surface prior to applying the particular surface modification layer to a particular surface, Or surface heat treatment of the surface that the surface modification layer will 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. In order to do so, a selection may be made for the major surfaces 776, 778 facing that predetermined interface 791-794.

If it is desirable to bulk anneal a stack of glass sheets 770-772 at a temperature up to 400 ° C. and separate each of the glass sheets from each other after the annealing process, then at any particular interface, eg, interface 791 Of Examples 2a, 2c, 2d, 2e, 3a, 3b, 4b-4e, Examples of Table 5, Examples of Tables 7-11 (discussed as alternatives to the examples of Table 10) Could be controlled using materials according to any one of examples 12a, 12b, 12c, 12g, 12g, or surface treatment with O ₂ only. More specifically, the first major surface 776 of the sheet 770 will be treated as “thin glass” in Tables 2-4, while the second major surface 778 of the sheet 771 Will be treated as a "carrier". The reverse is also true. A suitable time-temperature cycle with a temperature up to 400 ° C. then achieves the required time-temperature for the entire laminate, the desired degree of consolidation, 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 desirable to bulk anneal a stack of glass sheets 770-772 at a temperature up to 600 ° C. and separate each of the glass sheets from each other after the annealing process, then any particular interface, eg, Bonding at interface 791 can be controlled using the material according to any one of examples 2a, 2e, 3a, 3b, 4c, 4d, 4e, or the examples of Table 5, along with any associated surface treatment. Let's go. More specifically, the first major surface 776 of the sheet 770 will be treated as “thin glass” in Tables 2-4, while the second major surface 778 of the sheet 771 Will be treated as a "carrier". The reverse is also true. A suitable time-temperature cycle having a temperature up to 600 ° C. then achieves the required time-temperature for the entire laminate, the desired degree of compaction, the number of sheets in the laminate, as well as the sheets Could be selected based on the size and thickness of the.

Furthermore, bulk annealing and formation of bulk articles can be performed by properly configuring the surface modification layer between each stack of sheets and each pair of sheets. To control bonding when it is desirable to bulk anneal the laminate of glass sheets 770-772 at temperatures up to 400 ° C. and then covalently bond adjacent sheet pairs together to form article 2 Any suitable material and associated surface treatment could be used. For example, at the interface (or other desired bonding area 40), bonding at the interface between a pair of glass sheets to be formed on the article 2, for example, sheets 770 and 771, is (i) the sheet 770, 771 Surrounding (or at other desired coupling area 40), along with any associated surface treatment, including examples 2c, 2d, 4b, examples of Tables 7-11 (examples discussed as alternatives to examples of Table 10) ), Example 12a, 12b, 12c, 12g, 12g, or material according to any one of the examples of surface treatment with O ₂ only; and (ii) treated in the inner area of sheet 770, 771 (ie, (i) Examples 2a, 2e, 3a, 3a, along with any associated surface treatment, in the surrounding internal area, or in a desired controlled bonding area 50 where separation of one sheet from the other is desirable. , 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 zone 50 could then be performed at temperatures up to 600 ° C.

  The material and heat treatment could be selected appropriately for compatibility with each other. For example, any of the materials 2c, 2d, or 4b can be used in the coupling area 40 together with the material according to Example 2a for a controlled coupling area. Alternatively, the heat treatment of the bond area and controlled bond area could be adequately controlled to minimize the effects of heat treatment in one area that adversely affects the desired degree of bonding in adjacent areas.

  After appropriate selection of the surface modification layer 790 and associated heat treatment for the glass sheets in the laminate, the sheets are properly arranged into a laminate and then heated to 400 ° C. to make them permanent relative to each other. All of the sheets in the laminate could be bulk annealed without bonding to. The laminate can then be heated to 600 ° C. to form a covalent bond in the desired bond area of the adjacent pair of sheets to form an article 2 having a pattern of bond areas and controlled bond areas. Will. Bonding at the interface between a pair of sheets that are to be covalently bonded by a bonding zone 40 to form an article 2 and another pair of such sheets that form another adjacent article 2 Examples 2a, 2e, 3a, 3b, 4c, 4d, 4e, the materials of the examples in Table 5 and the associated heat could be controlled so that the two are not covalently bonded to each other. In this same manner of controlling the bond between adjacent articles, it would be possible to control the bond between the article and any cover sheets present in the laminate.

  Furthermore, similarly to the above, it is also possible to collectively form the articles 2 from the laminated body 760 without annealing the same laminated body 760 in advance. Instead, the sheet is annealed separately or annealed in a different laminate before the sheet is configured for the desired controlled bond in the laminate to manufacture the article together. Could be separated from Bulk annealing is simply omitted from the just described manner of bulk annealing and then forming the article together from one and the same laminate.

  Only the manner of controlling bonding at interface 791 has been described in detail above, but of course the same may be done at interface 792, or if there are more than 4 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 will bond without. In addition, the same manner of controlling binding may be used for any existing interface 791, 792, 793, 794, but different ones of the above-described manner of controlling binding may be used for different interfaces to achieve the desired The same or different results may be produced with respect to the type of binding.

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

  Once the sheet stack is bulk annealed, 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 chemical oxidation, SC1, or SC2) to remove the surface modification layer 790. . Individual sheets can be used as desired (eg, as a substrate for an electronic device such as 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 particularly, the sheet need not be maintained in a clean environment from beginning to end, as in a clean room slow cooling kiln. Instead, the laminate is formed in an uncontaminated environment, and then the sheet surface is processed in a standard slow-cooling kiln (ie, with an uncontrolled cleanliness) without getting particulate contamination. can do. This is because there is no fluid flow between the sheets. Therefore, the sheet surface is protected from the environment in which the laminate of sheets is annealed. After annealing, the sheets maintain some degree of adhesion and still remain separable from each other when sufficient force is applied without damaging the sheets, so that the sheet stack can be further processed ( Can be easily transported to (within the same or different equipment). That is, a glass manufacturer (for example) assembles and anneals a laminate of glass sheets and then ships the sheet as a laminate that remains together during shipping (without fear of separation of the sheet during shipping). The sheet could be separated from the laminate by a customer who would use the sheet individually or as a smaller group upon arrival at the destination. Once separation is desired, the sheet stack can be processed again in a clean environment (after cleaning the stack if necessary).

Example of bulk annealing The glass substrate was used as received from the fusion draw method. Glass compositions 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 produced by a 0.7 mm thick × 150 mm diameter fusion draw method by a lithographic method using a reference / vernier with a depth of 200 nm using HF. All the glass substrates were coated with 2 nm plasma deposited fluoropolymer as a surface modification layer on the entire bonding surface, ie 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 a “glass laminate”). The glass laminate was heated from 30 ° C. to 590 ° C. in a period of 15 minutes, held at 590 ° C. for 30 minutes in a nitrogen purged tube furnace, and then cooled to about 230 ° C. in a period of 50 minutes. 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 for each individual substrate by comparing the glass standard to an unannealed quartz control. Individual substrates were found to be compressed by about 185 ppm. Two substrates as separate samples (not stacked together) were subjected to the second annealing cycle described above (holding at 590 ° C./30 minutes). The compression was measured again and it was found that the substrates were further compressed by less than 10 ppm (actually 0 to 2.5 ppm) for the second heat treatment (after the second heat treatment-original glass dimensions). -The change in glass dimensions after the first heat treatment was subtracted from the change in glass dimensions). In this way, the inventors can coat, laminate, heat treat at high temperature to achieve compression, cool, separate into individual sheets, after the second heat treatment It was shown to have a dimensional change of less than 10 ppm and even less than 5 ppm (compared to the size after the first heat treatment).

Although the furnace in the annealing example described above was purged with nitrogen, the slow cooling furnace was air, argon, oxygen, CO, depending on the annealing temperature and the stability of the material of the surface modification layer at these temperatures in the particular environment. ₂ or other gases including combinations thereof may be purged. Instead of the 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 a spool form instead of a 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 treatment as previously described for the sheet, in which case the glass of the entire spool will be annealed without sticking to the adjacent one roll of glass. Upon unwinding from the roll, the surface modified layer may be removed by any suitable process.

Outgassing Polymeric adhesives used in typical wafer bonding applications are generally 10-100 micrometers thick and lose about 5% of their mass at or near its temperature limit. For such materials released from thick polymer membranes, it is easy to quantify the amount of mass loss or outgassing by mass spectrometry. On the other hand, measuring outgassing from a thin surface treatment of about 10 nm thickness or less, such as the above-described plasma polymer or self-assembled monolayer surface modification layer, and a thin layer of pyrolytic silicone oil is more Have difficulty. For such materials, mass spectrometry is not sensitive enough. However, there are many other methods for measuring outgassing.

  A first method for measuring a small amount of outgassing is based on surface energy measurements and will be 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 modified layer to be tested above, that is, a surface modified layer whose composition and thickness correspond to the surface modified layer 30 to be tested, represents the surface 902. The second substrate or cover 910 is positioned such that its surface 912 is in close proximity to but not in contact with the surface 902 of the carrier 900. Surface 912 is an uncoated surface, i.e. a bare surface of the material comprising the cover. Spacers 920 are placed at various points between the carrier 900 and the cover 910 to keep them spaced apart from each other. The spacer 920 is thick enough to separate the cover 910 from the carrier 900 and allow movement 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. Carrier 900, spacer 920, and cover 910 together form test article 901.

  Prior to assembling the test article 901, the surface energy of the bare surface 912 is measured 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 energy shown in FIG. 10 for both the polar and dispersive components was 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. Heating is performed under N ₂ gas that flows at atmospheric pressure, ie, flows 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, eg, due to evaporation, pyrolysis, decomposition, polymerization, reaction with the support, and dewetting) are due to 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 modification layer has caused outgassing, but its properties change, for example, due to the mechanism described above, so at that temperature The general instability of the material is shown. Therefore, the smaller the change in the surface energy of the surface 902, the more stable the surface modified layer. On the other hand, because 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. Therefore, the change in surface energy of the surface 912 is a substitute for outgassing of the surface modification layer present on the surface 902.

Thus, one test for outgassing uses a change in the surface energy of the cover surface 912. Specifically, when there is a change in the surface energy of the surface 912 of 10 mJ / m ² or more, there is gas emission. This amount of surface energy change is consistent with contamination that can result in loss of film adhesion or degradation of material properties and device performance. The change in the surface energy of 5 mJ / m ² or less is close to the reproducibility of the surface energy measurement and the unevenness of the surface energy. This small change is consistent with minimal outgassing.

During the test that produced the results of FIG. 10, the carrier 900, cover 910, and spacer 920 are alkali-free aluminoborosilicate display glasses obtained from Corning Incorporated, Corning, NY, “Eagle XG "Made from glass, but that is not necessary." The carrier 900 and the cover 910 had a diameter of 150 mm and a thickness of 0.63 mm. In general, the carrier 910 and the cover 920 are manufactured from the same material as the carrier 10 and the thin sheet 20, respectively, and it is desirable to perform a gas emission test on them. During this test, the silicon spacer is 0.63 mm thick, 2 mm wide, and 8 cm long, thereby forming a 0.63 mm gap between the surfaces 902 and 912. During this test, the bath 930 was incorporated into the MPT-RTP600s rapid heat treatment apparatus, which was periodically ramped up from room temperature to the test limit temperature at a rate of 9.2 ° C. per minute. It was held at the test limit temperature for various times as indicated in Time and then cooled to 200 ° C. at the furnace speed. After the furnace cooled to 200 ° C., the test article was removed and after the test article cooled to room temperature, the surface energy of each surface 902 and 912 was measured again. Thus, as an example, using material # 1 data for changes in the surface energy of the cover, tested at line 1003 to a limit temperature of 450 ° C., data was collected as follows. The data point at 0 minutes indicates a surface energy of 75 mJ / m ² (millijoule per square meter), which is the surface energy of bare glass, ie no time-temperature cycle has yet been performed. The data point at 1 minute indicates 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) Was placed in a heating bath 930 at room temperature and atmospheric pressure; the test limit temperature was 450 ° C. at a rate of 9.2 ° C. per minute while flowing 2 liters of N ₂ gas per minute under standard conditions. And was held at a test limit temperature of 450 ° C. for 1 minute; the vessel was then cooled to 300 ° C. at a rate of 1 ° C. per minute, and then article 901 was removed from vessel 930; The article was cooled to room temperature (not an N ₂ flowing atmosphere); the surface energy of surface 912 was then measured and plotted as a 1-minute point on 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 # Test either 450 ° C or 600 ° C to match the data points for material 5 (lines 1503, 1504), material # 6 (lines 1603 and 1604), and material # 7 (lines 1703, 1704), respectively. 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 representing the surface energy of the surface 902 with respect to the corresponding surface modification layer material (material # 1-7) And 1702 were determined similarly except that the surface energy of surface 902 was measured after each time-temperature cycle.

  The seven different materials described below were subjected to the assembly process described above and a time-temperature cycle. The result is shown graphically in FIG. Of the seven types of materials, materials # 1 to 4 and 7 correspond to the materials of the surface modification layer described above. 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 has not changed significantly. This material is therefore very stable at temperatures between 450 ° C. and 600 ° C. Moreover, as indicated by lines 1003 and 1004, the surface energy of the cover was not significantly changed, ie, the change is 5 mJ / m ² or less. 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% toluene solution of phenyltriethoxysilane 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 noted above, this indicates some change in the surface modified layer, and material # 2 is relatively more unstable than material # 1. However, as shown by lines 1203 and 1204, the change in the surface energy of the cover is less than 5 mJ / m ² , indicating that the change to the surface modification layer did not result in outgassing.

Material # 3 is a SAM of pentafluorophenylsilane deposited from a 1% toluene solution of pentafluorophenyltriethoxysilane 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 noted above, this indicates some change in the surface modification layer, and material # 3 is relatively more unstable than material # 1. However, as shown by lines 1303 and 1304, the change in the surface energy of the cover is 5 mJ / m ² or less, indicating that the change to the surface modification 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 noted above, this indicates some change in the surface modification layer, and material # 4 is relatively more unstable than material # 1. Moreover, the change in the surface energy of the carrier with respect to material # 4 is greater than that of any of materials # 2 and # 3, and material # 4 is relatively more unstable than materials # 2 and # 3. Indicates that there is. However, as shown by lines 1403 and 1404, the change in the surface energy of the cover was 5 mJ / m ² or less, and changes to the surface modification layer did not result in outgassing affecting the surface energy of the cover. It shows that. However, this is consistent with the manner in which HMDS outgases. That is, HMDS outgases ammonia and water, which do not affect the surface energy of the cover and will not affect the manufacturing equipment and / or processing of some molecular parts. On the other hand, if the outgassing product is 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 glycidoxypropyl silane deposited from a 1% toluene solution of glycidoxypropyltriethoxysilane and cured in a vacuum oven at 190 ° C. for 30 minutes. This is a comparative material. As indicated by lines 1501 and 1502, there is relatively little change in the surface energy of the carrier, but there is a significant change in the surface energy of the cover, as indicated by lines 1503 and 1504. That is, material # 5 is relatively stable on the support surface, but it actually outgases a significant amount of material onto the cover surface, which changed the surface energy of the cover by more than 10 mJ / m ² . . 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 . For example, see the 1 and 5 minute data points. Without wishing to be bound by theory, it is believed that the slight increase in surface energy from 5 to 10 minutes is due to some of the outgassing material being decomposed and peeled off the cover surface.

Material # 6 dispenses 5 ml of Dow Corning 704 diffusion pump oil tetramethyltetraphenyltrisiloxane (obtained from Dow Corning) onto the support and puts it on a hot plate at 500 ° C. in air for 8 minutes. DC704 silicone coating prepared by placing. Completion of sample preparation is indicated by the end of visible fuming. After preparing the samples in the manner described above, the gas release test described above was performed. This is a comparative material. As shown in FIG. 10, lines 1601 and 1602 show some change in surface energy on the support. As described above, this indicates some change in the surface modified layer, and material # 6 is relatively more unstable than material # 1. Moreover, as indicated by lines 1603 and 1604, the change in the surface energy of the cover is greater than 10 mJ / m ² , indicating significant outgassing. More specifically, at a test limit temperature of 450 ° C., a 10-minute data point indicates a decrease in surface energy of approximately 15 mJ / m ² and a greater decrease in surface energy at 1 and 5 minutes. Yes. Similarly, for a change in the surface energy of the cover during the cycle at a test limit temperature of 600 ° C., the decrease in the surface energy of the cover is about 25 mJ / m ² at the 10 minute data point and is somewhat larger at 5 minutes, It was somewhat small in 1 minute. In summary, however, this material showed a significant amount of outgassing over the entire range of testing.

Material # 7 is a CH ₄ —H ₂ plasma deposited polymer that is subsequently treated with N ₂ —O ₂ and N ₂ plasma for a short period of time. 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 has not changed significantly. This material is therefore very stable at temperatures between 450 ° C. and 600 ° C. Moreover, as indicated by lines 1703 and 1704, the surface energy of the cover was not significantly changed, ie, the change is 5 mJ / m ² or less. Therefore, there was no outgassing for this material from 450 ° C to 600 ° C.

  Importantly, for materials # 1-4 and 7, the surface energy over the entire time-temperature cycle is that the cover surface remains at a surface energy consistent with that of bare glass, i.e. the carrier surface. This indicates that the material outgassed from 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 thin sheet was prepared is that the article (thin sheet bonded together with the carrier by a surface modification layer) resists FPD processing. Make a big difference whether or not. Thus, although the material # 4 example shown in FIG. 10 may not outgas, this material may or may not withstand a 400 ° C. or 600 ° C. test as described with respect to the discussion in Table 2. It may not be.

  A second method for measuring a small amount of outgassing is based on an assembled article, i.e., an article in which a thin sheet is bonded to a support through a surface modification layer, and is based on the percentage of bubble area to determine outgassing. Use change. That is, during the heating of the article, bubbles formed between the carrier and the thin sheet indicate outgassing of the surface modified layer. As described above with respect to 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 pyrolytic silicone oil surface treatments) will still produce bubbles during heat treatment, despite smaller absolute mass loss . Formation of bubbles between the thin sheet and the carrier will cause problems with alignment during pattern generation, photolithography processing, and / or device processing on the thin sheet. Moreover, bubble generation at the boundary of the bonding area between the thin sheet and the carrier will cause problems with process fluids from certain processes that contaminate downstream processes. A change in bubble area% of 5 or more is significant, indicating outgassing and is undesirable. On the other hand, a change in bubble area% of 1 or less is negligible indicating no outgassing.

The average bubble area of bonded thin glass in a Class 1000 clean room for manual bonding is 1%. The percent air bubbles in the bonded carrier is a function of the cleanliness of the carrier, the thin glass sheet, and the surface treatment. Since these initial defects serve as nucleation sites for bubble growth after heat treatment, any change in bubble area upon heat treatment of less than 1% is within sample preparation variability. To perform this test, a commercial desktop scanner equipped with a transparent unit (Epson Expression 10000XL Photo) was used to create a first scanned image of the thin sheet immediately after bonding and the area where the carrier is bonded. 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 in the scanner without a sample) Prepare the image by: The bonded area is then analyzed using standard image processing techniques such as thresholding, hole 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 bubble area is then compared to the total bond area (ie, the total overlap area between the thin sheet and the carrier) to calculate the area% of the bubbles in the bond area relative to the total bond area. The sample is then heat treated for up to 10 minutes in an MPT-RTP600s Rapid Thermal Processing system at a test limit temperature of 300 ° C., 450 ° C., and 600 ° C. in an N ₂ atmosphere. Specifically, the time-temperature cycle performed included: the article was placed 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 temperature for 10 minutes; the bath was then cooled to 200 ° C. at the furnace speed; the article was removed from the bath and allowed to cool to room temperature; the article was then scanned a second time with an optical scanner. Did. The bubble area% from the second scan was then calculated as before and the change in bubble area% (Δ bubble area%) was determined relative to the bubble area% from the first scan. As mentioned above, a change in bubble area of 5% or more is significant and indicates outgassing. A change in the bubble area% was chosen as a metric because of the variation in the original bubble area%. That is, most surface modification layers have about 2% bubble area in the first scan because of handling and cleanliness after thin sheets and carriers have been prepared and before being bonded. Have. However, variation can occur between materials. The same set of materials # 1-7 as described for the first outgassing test method was again used for this second outgassing test method. Of these materials, materials # 1 to 4 showed about 2% bubble area in the first scan, whereas materials # 5 and # 6 were significantly larger bubble areas in the first scan, That is, about 4% was shown.

  The result of the second gas emission test will be described with reference to FIGS. The gas release test results of materials # 1 to # 3 and # 7 are shown in FIG. 11, whereas the gas release test results of materials # 4 to 6 are shown in FIG.

  The results for material # 1 are shown as square data points in FIG. As can be seen from the figure, the change in bubble area% was almost zero for the test limit temperatures of 300 ° C, 450 ° C, and 600 ° C. Thus, material # 1 does not exhibit gas evolution at these temperatures.

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

  The results for material # 3 are shown as triangular data points in FIG. As can be seen from the figure, similar to the results for material # 1, the change in bubble area% was nearly zero for the test limit temperatures of 300 ° C, 450 ° C, and 600 ° C. Therefore, material # 3 does not exhibit gas evolution at these temperatures.

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

  The results for material # 4 are shown as circular data points in FIG. As can be seen from the figure, the change in bubble area% is nearly zero for the 300 ° C. test limit temperature, but close to 1% for some samples at the test limit temperatures of 450 ° C. and 600 ° C. For the sample, it is about 5% at 450 ° C. and 600 ° C. test limit temperatures. The results for material # 4 are very inconsistent and depend 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 this material example and related discussion discussed above with respect to Table 2. For this material, it was noted that samples with a change in bubble area% of close to 1% for the test limit temperatures of 450 ° C. and 600 ° C. were not able 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 limit the generation of bubbles. On the other hand, a sample with a change in bubble area percentage close to 5% was able to separate the thin sheet from the carrier. Thus, samples that did not outgas have the undesirable consequence of increased adhesion after temperature treatment that sticks the carrier and thin sheet together (prevents removal of the thin sheet from the carrier), while thin Samples that allowed removal of the sheet and carrier had undesirable results of outgassing.

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

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

Bonded displays of polymer surfaces to glass surfaces have 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 with PEN. Layers of polymeric adhesive up to 100 micrometers thick are commonly used to laminate PEN and PET onto glass carriers for sheet-to-sheet processing. The mass loss of these adhesives during device processing is generally greater than 1%, which creates a problem with contamination due to solvent outgassing. Moreover, complete removal of the adhesive is difficult and therefore the glass carrier is generally not reused.

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

  There are three transistor technologies in mass production for FPD backplane manufacturing: 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 for substrates that enable high temperature processes, as well as requirements for chemical, mechanical and vacuum compatibility, has been a major limitation 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. The device structure is fabricated with a number of subtractive cycles of material deposition and photolithography 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 high temperatures. The Laser and strobe annealing enable p-Si crystallization without excessive heating of the substrate, but uniformity is a challenge and performance is poor compared to glass substrates. Patterns are formed on the plurality of layers by photolithography patterning of a 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 high temperature solvent, typically with ultrasonic or megasonic agitation.

  Removing the thick layer of adhesive prevents the carrier from being reusable. 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, the plasma process is not practical for removing those layers. A major challenge for organic thin film transistor manufacturing is the lamination of thin polymer sheets onto 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. Have been described. The formation of a surface modification layer on the glass carrier results in a temporary bond with moderate adhesion between the thin polymer sheet and the carrier. This moderate adhesion is achieved by optimizing the van der Waals and shared attractive energy contributions to the total adhesion energy 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 the polymer sheet can be peeled from the carrier by applying sufficient peel force Can be left. Since the surface modification layer has a thickness of less than 1 micrometer and is easily removed in oxygen plasma, the device manufactured on the thin polymer sheet can be removed and the carrier can be reused by peeling. is there.

  In order to create a reasonable bond between the thin polymer sheet and the glass carrier, the following advantages of using a thin surface modification layer would be obtained.

  (1) Since the amount of material used to bond the thin polymer sheet to the carrier is reduced by about 100 times compared to commercially available adhesives, the possibility of absorbing gas emissions and contaminants 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 possibility of outgassing and process contamination.

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

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

  PEN and PET are among the commonly selected polymer substrates obtained in roll form for electronic component manufacturing. Compared to most polymers, they are relatively chemically inert, have low water absorption, low expansion, and temperature resistance. 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 lower than the operating temperature above 600 ° C. for display glass suitable for pSi processing. The 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 far exceeds the relaxation and compression in glass at significantly higher temperatures. These inferior physical properties of polymer substrates require process adaptation to deposit high quality devices in high yield. For example, the deposition temperature of silicon dioxide, silicon nitride and amorphous silicon must be lowered to stay within the limits of the polymer substrate.

  The aforementioned physical properties of the polymer make it difficult to bond to a rigid carrier for sheet-to-sheet processing. For example, the thermal expansion of polymer sheets is typically more than 6 times that of display glass. Despite the low upper temperature limit, thermal stresses are warped and curved enough to cause delamination when using conventional bonding techniques. The use of high expansion glass such as soda lime or higher expansion metal supports helps to manage the warpage challenges, but these supports typically contain contamination, suitability or roughness (thermal transfer ).

The surface energy of PEN and PET is also significantly lower than that of glass. As shown in Table 16 below, “Corning” “Eagle XG” glass exhibits a surface energy of about 77 mJ / m ² after cleaning with SC1 chemistry and standard cleaning techniques. See Example 16e. Without surface treatment, PEN and PET have a surface energy of 43-45 mJ / m ² (43-45 dynes) and are nonpolar. “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 (eg, with oxygen plasma) significantly increases the surface energy to 55-65 mJ / m ² (55-65 dynes, “plasma”) by increasing the polar component. 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 (“time course”).

With 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, the polymer sheet allows processing of the structure on the sheet. Although it would not stick to the glass carrier enough to do so, the polymer could not be peeled from the glass carrier when first fixed on the glass carrier and then heated to a moderate temperature. Therefore, it has been found useful to first match the surface energy of the glass carrier to the surface energy of the PEN or PET in order to initially bond the PEN or PET to the glass at room temperature. In addition, the various surface modification layers described above are polymer layers even after an organic-TFT processing cycle (including 1 hour 120 ° C. vacuum anneal and 1 minute 150 ° C. post-bake step). It has been found that the binding energy is controlled so that can be peeled from the glass carrier.

By selecting an appropriate surface modification layer to appropriately adjust the surface energy of the glass carrier, a polymer, for example, PEN or PET, is applied to the glass carrier by organic-TFT processing (vacuum at 120 ° C. for 1 hour). To achieve adequate wetting and adhesion strength to allow the polymer to be removed from the support after processing while controllably binding in a manner suitable for annealing and post-baking at 150 ° C. for 1 minute) it can. The polymer sheet can be successfully removed from the carrier, ie the polymer sheet is between the OTFT on the polymer sheet and the OTFT on the mask used to produce it, even after the above treatment. If there is no significant difference in transistor placement, the polymer sheet is controllably coupled to the carrier. The surface modification layer may be selected from a variety of materials and processes exemplified throughout the specification. The polymeric material may be conveniently plasma cleaned prior to bonding (to increase the polar component of the surface energy to promote initial bonding), but the current polymer (ie, as received, This is not necessary because the surface energy of the glass support can be significantly changed to achieve a level suitable for controlled bonding with the washed or time-varying state. Realizing a surface energy in the range of about 36 mJ / m ² (Example 5g) to about 80 mJ / m ² (Example 5f) on the binding surface of the glass carrier, based on the examples described above and Table 16 below. Can do.

Some of the surface modification methods described above, including those formed from plasma polymerization of hydrocarbon sources, eg, hydrocarbon gases, are suitable for bonding polymer sheets to glass carriers. For example, plasma polymer films deposited from fluorocarbon gas (Examples 5a and 5g); plasma polymer films deposited from fluorocarbon gas, followed by simultaneous treatment with nitrogen and hydrogen (Example 5m); Plasma polymer films deposited from non-fluorine-containing gases (Examples 6a-6j); Plasma polymer films deposited from various mixtures of hydrocarbons, optionally 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, where these surface energies vary in cleanliness and / or aging Useful for the polymer in this state; and deposited from various non-fluorine-containing gases, followed by sequential treatment 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 films, all of which will work particularly well for plasma cleaning PEN. For polymers other than PET or PEN, other surface treatments are suitable depending on the surface energy of the polymer present immediately before bonding, as it may be affected by the degree of cleaning and the degree of aging. Let's go. After the organic-TFT type processing (including vacuum annealing at 120 ° C. for 1 hour and post-baking step at 150 ° C. for 1 minute), the surface energy of the glass carrier that approximately matches the surface energy of the polymer sheet Has been found to work well in both initial binding and bond control.

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

An example of using a plasma polymerized film to adjust the surface energy of a surface modified layer bonded surface formed from a mixture of gases , cover it with surface hydroxyl and / or control the type of polar bond thereon Deposition of a thin film of a surface modification layer from a mixture of feed gases, including hydrocarbons (eg, methane). The deposition of the surface modification layer may be performed under atmospheric pressure or reduced pressure, and plasma excitation such as DC or RF parallel plates, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF Performed by plasma. The plasma polymerized surface modification layer may be deposited on the binding surface of the support, the thin sheet, or both. As described above for the examples in Table 3, plasma polymerization forms a layer of highly crosslinked material. Reaction conditions and feed gas control can be used to control the thickness, density, and chemistry for tailoring the functional groups to the desired application. By controlling the properties of the membrane, including the amount of surface hydroxyl that is 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 example of Table 16 below, various conditions were used to deposit the plasma polymerized film on the glass support. The glass support was a substrate made from “Corning” “Eagle XG” (obtained 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 membrane was deposited in an STS Multiplex PECVD apparatus in triode electrode placement mode (obtained from SPTS, Newport, UK) where the carrier was placed on the platen, to which 50 W of 380 kHz RF energy was applied. The coil (shower head) was placed on the platen, 300 W of 13.5 MHz RF energy was applied thereto, the platen temperature was 200 ° C., and the gas flow rate through the shower head was as shown in Table 16 (Flow rate is cubic centimeter per minute-sccm under standard conditions). Thus, for example, the notation of the column “Surface Modification Layer Deposition Process” in Table 16 for Example 16b can be read as follows: In a STS Multiplex PECVD apparatus, at a platen temperature of 200 ° C. and a pressure of 300 mTorr 200 sccm H ₂ , 50 sccm CH ₄ , and 50 sccm C ₂ F ₆ were flowed together in a (about 40 Pa) bath through a showerhead; 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; the deposition time was 120 seconds. The surface treatment column notation for the remaining examples can be read similarly. The surface energy is calculated in mJ / m ² (square meter) by using the contact angle (CA) and Wu model of three different test liquids (in this case water (W), hexadecane (HD), and diiodomethane (DIM)). Per millijoule). For surface energy, the polar (P) and dispersed (D) components and the total (T) are shown. For these examples, the thickness “Th (A)” of the surface modification layer expressed in angstroms is also shown.

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

  Examples 16a to 16d show that a surface modification layer is deposited on the glass surface to change its surface energy and thus the surface of the glass is tailored for 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 a cleaned glass support. Thus, deposition of the surface modification layer has been shown to reduce the surface energy from about 77 to about 49 mJ / m ^2, which is within the range of surface energy on a typical polymeric binding surface. Yes.

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

Example 16c shows that the surface modification layer can be a plasma polymerized film deposited from a mixture of hydrogen, methane (hydrocarbon), and nitrogen-containing gas (eg, N ₂ ). In this example, the surface modification layer was deposited on a cleaned glass support. Thus, the deposition of the surface modification layer results in a surface energy of about 77 to about 61 mJ / m ² (which is on a typical polymer binding surface treated with O ₂ plasma, such as during cleaning of the polymer sheet. It is shown to be within a range of surface energy. This surface energy is also within a 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 support. Thus, the deposition of the surface modification layer reduces the surface energy to about 77 to about 57 mJ / m ² (which again falls within the range of surface energy on a typical polymeric binding surface). It is shown. Also, for some applications this may be suitable for bonding the carrier to a thin glass sheet.

The surface energy achieved by Examples 16c and 16d compared to the surface energy achieved by Example 16a is similar to the deposition gas otherwise when nitrogen (either N ₂ or NH ₃ ) is added to the deposition gas. It can be shown that the surface energy achieved 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 a thin sheet of glass to a glass carrier). However, this surface modification layer is suitable for bonding a polymer bonding surface to a glass bonding surface. In addition, the surface modification layer of Examples 16c and 16d (formed from plasma polymerization of hydrocarbon (methane), optionally hydrogen-containing gas (H ₂ ), and nitrogen-containing gas (N ₂ or ammonia)) It should be noted that the surface energy generated by is greater than about 50 mJ / m ² and therefore may be adapted to bond a thin glass sheet to a glass carrier in some cases.

  A thin sheet bonded to a carrier having a surface modified layer deposited thereon as in Examples 16a to 16d of Table 16 was manufactured from TEONEX® Q65 PEN (obtained from DuPont) and was 200 micrometers. The thickness of the substrate was as follows.

  As in the example of Table 16, the bonding surface with the surface modification layer disposed thereon was glass, but this is not necessary. Alternatively, the bonding surface may be another suitable material having surface energy and properties similar to glass, such as silicon, polysilicon, single crystal silicon, ceramic, glass ceramic, sapphire, or quartz.

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

  As a counter example, a polymer film was deposited on a SC1 cleaned bare glass support (Example 16e). However, the polymer sheet did not stick to the carrier enough to process the structure on the polymer sheet.

  In order to be suitable for organic-TFT processing, it is required to be higher than the wet and bond strength. The very different thermal expansion between the polymer membrane and the support is best managed by choosing a high expansion glass to minimize the difference in expansion and by reducing the rate of heating and cooling processes. The The need for a smooth and clean substrate surface with minimal water absorption during processing would be achieved by spinning and curing a thin layer of a suitable organic dielectric. Both of these flatten the surface and form a moisture and other contaminant barrier.

A surface modified layer process was used to bond PEN ("TEONEX" Q65 200 micrometer thick sheet from DuPont) to a "Corning""EagleXG" glass support. Very good bonding performance was observed 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, 200 ° C. platen on the showerhead. 50 W of 380 kHz RF energy and a deposition time of 2 minutes. Prior to bonding, PEN was exposed to a UV-ozone cleaner for 5 minutes. Because this has been found to improve adhesion. PEN was applied using a Teflon (R) squeegee. An approximately 150 nm thick alicyclic epoxy layer was spun on PEN and cured to planarize surface defects. The organic gate insulator (OGI) was a photopatternable alicyclic 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, patterned by lithography with Fuji 6512 resist, and a pattern was formed on the gate by wet etching in an A-type Al etchant. The photoresist was removed in 3 minutes in a room temperature PGMEA bath and then rinsed with IPA / DI (NMP release agent was incompatible with 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 is fast, the etching product is slow to dissolve, so that the etching is difficult. Very good results were obtained after 5 seconds of etching, removal of etching products by spraying with deionized water, and 4 to 5 repetitions thereof. It was difficult to wet the tetrathienoacene-DPP copolymer (PTDPPPFT4) organic semiconductor (OSC) layer. 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. The OSC was applied by spinning in a Laurel spinner with manual dispensing, 20 seconds rest, 30 seconds 500 rpm, 60 seconds 1000 rpm. The OSC film was soft baked at 90 ° C. for 2 minutes on a hot plate and vacuum annealed at 120 ° C. for 1 hour in a low vacuum Salvis oven to remove residual decalin. Using a brief 5 second O ₂ plasma in Branson to improve adhesion, the third OGI layer was spun onto the OSC, exposed for 2.5 seconds, 1 minute rest, and 1 minute An optical pattern was directly formed by post-baking at 150 ° C. After a 1 minute rest, the active pattern was tray developed in PGMEA for 1 minute, followed by IPA and DI rinses. Using 15 sccm O ₂ , 10 sccm Ar, 20 sccm CHF ₃ , dry etching in Unaxis 790 RIE using 200 milliwatts (200 Pa) for 15 seconds to form the active pattern The gate metal was exposed. The performance of 75/75 μm TFTs is summarized in the table shown in FIG. This table shows a typical bottom gate, bottom contact organic thin film transistor fabricated on PEN controllably bonded to the glass carrier described above, with a typical channel width of 75 micrometers and channel length of 75 micrometers. Figure 2 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 there was no noticeable difference in transistor placement between the OTFT on the polymer sheet and the OTFT on the mask used to make it, the polymer sheet was even after processing as described above. It was successfully removed from the carrier.

  The above-described process for forming an array of bottom-gate and bottom-contact organic thin film transistors can be performed with a suitable surface modification layer selected from those described herein with “Corning” Gorilla® Glass (Corning, NY). PEN sheet ("TEONEX" Q65 200-micrometer sheet from DuPont) that is controllably bonded to a carrier made from Corning Incorporated, Inc. I did it well.

  As described above, the polymer itself may be a substrate on which other devices can be manufactured. Alternatively, the polymer may be a polymer surface on a composite substrate, such as a glass / polymer composite. In this case, the polymer surface of the glass / polymer composite will face the carrier and be bonded 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 fabricated. After the electrons or other structures are produced on the glass surface of the glass / polymer composite, the polymer surface of the composite may be peeled from the surface modification layer on the support. In this embodiment, the glass layer in the glass / polymer composite is particularly thin, for example, the thickness is 50 micrometers or less, 40 micrometers or less, 30 micrometers or less, 20 micrometers or less, 10 micrometers or less, or It may be convenient when it is below 5 micrometers. In such a case, the polymer portion of the glass / polymer composite serves not only as a binding surface for attaching the composite to the support, but also to the composite when the composite is not on the support. It will give handling advantages.

CONCLUSION It is emphasized that the above-described embodiments of the present invention, and in particular any "preferred" embodiment, are merely possible examples of implementation and merely provide a clear understanding of the various principles of the 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 herein within the scope of this disclosure and the present invention and protected by the following claims.

  For example, although the surface modification layer 30 of many embodiments is shown and discussed as being formed on the carrier 10, it may alternatively or additionally be formed on the thin sheet 20. . That is, as required, materials such as those described in Tables 3-12 and 16 are applied to the carrier 10, the thin sheet 20, or both the carrier 10 and the thin sheet 20 on the side to be bonded together. Also good.

  Further, although some surface modification layers 30 have been described as controlling the bond strength such 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., of course, The article 2 is processed at a temperature below the temperature of the specific test that the article passed and still achieves 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 to do.

  Furthermore, although the concept of controlled bonding has been described herein as used for the carrier and thin sheet, in certain situations, the concept may cause the sheets (or portions thereof) to be separated from each other. It can also be applied to control the bond between thicker sheets of glass, ceramic, or glass ceramic, which may be desirable.

  Still further, although the concept of controlled bonding herein has been described as useful for glass carriers and thin sheets of glass, the carriers can be made from other materials, such as ceramics, glass ceramics, or metals. May be. Similarly, the sheet controllably coupled to the carrier may be made from other materials, such as ceramic or glass ceramic.

  Furthermore, although the surface modification layers of Examples 3 and 3-12 above have been described as being formed by plasma polymerization, other techniques such as thermal evaporation, sputtering, UV of gas species that react with the bonding surface, etc. It may also be possible by activation or wet chemistry.

Furthermore, although the carbonaceous surface modification layers formed by plasma polymerization of Examples 6-12 were formed using methane as the polymer forming gas, other carbon-containing feedstocks may be possible. For example, the carbon-containing source is 1) a hydrocarbon (alkane, alkene, alkyne or aromatic compound. Alkanes include, but are not limited to, methane, ethane, propane and butane; Examples include, but are not limited to, ethylene, propylene, and butylene; alkynes include, but are not limited to, acetylene, methylacetylene, ethylacetylene, and dimethylacetylene; aromatic compounds are not limited to Benzene, toluene, xylene, ethylbenzene); 2) alcohol (including methanol, ethanol, propanol); 3) aldehyde or ketone (including formaldehyde, acetaldehyde and acetone); 4) amine (methylamine, dimethyl) Amines, 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 can include one or more of the following: 1) saturated or unsaturated hydrocarbons, or 2) nitrogen-containing or 3) oxygen-containing saturated or unsaturated hydrocarbons, 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 modified layer was used to treat and thereby increase the surface energy as in Examples 5 and 8-12 or as in Examples 7, 16c, 16d The polar groups used to form itself were nitrogen and oxygen, but other polar groups such as sulfur and / or phosphorus may be possible.

In addition, N ₂ and NH ₃ were used as nitrogen-containing gases, but other nitrogen-containing materials such as hydrazine, N ₂ O, NO, N ₂ O ₄ , methylamine, dimethylamine, trimethylamine and ethylamine, acetonitrile Is sometimes used.

The oxygen-containing gases used were N ₂ —O ₂ and O ₂ , but other oxygen-containing gases such as 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, surface modified layers, including those subsequently processed, can be from about 1 nm (Example 16b) or 2 nm (Examples 3 and 4) to about 10 nm (Example 12c, 8.8 nm). Can be achieved. Moreover, 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-described concepts according to the present application may be combined with each other in any and all different ways of combination. As an example, various concepts may be combined according to the following aspects.

According to a first aspect, a method for controllably bonding a thin sheet to a carrier comprising:
Obtaining a thin sheet having a thin sheet bonding surface;
Obtaining a carrier having a carrier binding surface;
Depositing a surface modification layer on at least one of the thin sheet binding surface and the carrier binding surface to obtain a first surface energy on one of the thin sheet binding surface and the carrier binding surface;
Treating the surface modified layer to change the first surface energy to a second surface energy greater than the first surface energy, and the thin sheet bonded surface through the surface modified layer to the carrier bonded surface Bonding to
Is provided.

According to the second aspect, the surface modification layer comprises:
Plasma polymerization of a carbon-containing gas to form a layer, followed by treatment of the layer with a nitrogen-containing gas, plasma polymerization,
Plasma polymerization of a carbon-containing gas to form a layer, followed by a first gas that is one of a nitrogen-containing gas and a hydrogen-containing gas, and then a second gas that is the other of the nitrogen-containing gas and the hydrogen-containing gas. Plasma polymerization, in which a continuous treatment of the layer with two gases is performed,
Plasma polymerization of a carbon-containing gas to form a layer, followed by treatment of the layer with an oxygen-containing gas, plasma polymerization,
Plasma polymerization of a carbon-containing gas to form a layer, followed by treatment of the layer with nitrogen and oxygen-containing gas, and plasma polymerization of the carbon-containing gas to form a layer, Plasma polymerisation, followed by continuous treatment of the layer with a first gas that is a nitrogen and oxygen containing gas and then a second gas that is a nitrogen containing gas,
The method of aspect 1 is provided, wherein the method is deposited and processed by one of the following:

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

According to a fourth aspect, the carbon-containing gas, methane, ethane, propane, butane, ethylene, propylene, propyne, acetylene, CO, and of CO ₂ comprising at least one method of embodiment 3 is provided .

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

According to the sixth aspect, when a hydrogen-containing gas is used, the hydrogen-containing gas contains H ₂ , and when an oxygen-containing gas is used, the oxygen-containing gas is O ₂ , O ₃ , H _2. A method according to any one of embodiments 2-5, comprising at least one of O, methanol, ethanol, propanol, N ₂ O, NO, and N ₂ O ₄ is provided.

  According to a seventh aspect, there is provided the method according to any one of aspects 2 to 6, further comprising a step of flowing hydrogen together with the carbon-containing gas during the plasma polymerization.

  According to an eighth aspect, there is provided the method according to any one of aspects 2, 3, and 5 to 7, wherein the carbon-containing gas is fluorocarbon.

  According to a ninth aspect, any one of aspects 2-8, wherein the surface modified layer is deposited from a mixture of a polymer-forming gas and a second gas, the second gas being 30% or more of the total mixture. One method is provided.

  According to a tenth aspect, there is provided the method of aspect 9, wherein the second gas is hydrogen.

  According to an eleventh aspect, there is provided the method of aspect 9, wherein the second gas comprises an inert gas.

  According to a twelfth aspect, there is provided the method of any one of aspects 1-11, wherein the thin sheet bonded surface comprises glass.

  According to a thirteenth aspect, there is provided the method of any one of aspects 1-12, wherein the carrier binding surface comprises glass.

  According to a fourteenth aspect, in the method of aspect 13, wherein the at least one of the thin sheet binding surface and the carrier binding surface has an average surface roughness Ra of 1 nm or less prior to the deposition of the surface modified layer. Provided.

According to the fifteenth aspect, at least one of the thin sheet bonding surface and the carrier bonding surface has an average surface roughness Ra of 1 nm or less after deposition of the surface modification layer and subsequent removal by O ₂ plasma. A method according to aspect 13 or aspect 14 is provided.

According to the sixteenth aspect, the carrier binding surface has a first average surface roughness Ra1 before deposition of the surface modified layer, and the carrier deposits the surface modified layer thereon. And having a second surface roughness Ra2, after which it is removed by O ₂ plasma cleaning, the difference between Ra1 and Ra2 is less than 1 nm, and the average surface roughness measurement is 5 × 5 micrometers A method of aspect 13 or aspect 14 is provided that is carried out over an area of.

  According to a seventeenth aspect, there is provided the method of any one of aspects 1-16, wherein the thickness of the thin sheet is 300 micrometers or less.

  According to an eighteenth aspect, there is provided the method according to any one of aspects 1 to 17, wherein the thickness of the surface modification layer is 1 to 70 nm.

  According to a nineteenth aspect, there is provided the method according to any one of aspects 1 to 17, wherein the thickness of the surface modification layer is 2 to 10 nm.

According to a twentieth aspect, at least one of the thin sheet bonding surface and the carrier bonding surface includes glass, and the surface modification layer and its treatment cause the first to 41 m to 80 mJ / m ² on the bonding surface. A method according to any one of aspects 1-19 is provided wherein a surface energy of 2 is achieved.

According to aspect A, in a glass article,
A carrier having a carrier binding surface;
A surface modification layer disposed on the carrier binding surface, wherein the carrier binding surface is bonded to the glass sheet bonding surface by a surface modification layer therebetween, in a bath of 9. The article is subjected to a temperature cycle that is heated from room temperature to 600 ° C. at a rate of 2 ° C., held at a temperature of 600 ° C. for 10 minutes, then cooled to 300 ° C. at 1 ° C. per minute, and then from the bath 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 modification layer during the temperature cycle, A surface modification layer configured such 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 is provided.

According to aspect B, in a glass article,
A carrier having a carrier binding surface;
A sheet having a sheet binding surface;
A surface modification layer disposed on one of the carrier binding surface and the sheet binding surface;
With
The carrier binding surface is bonded to the sheet bonding surface by a surface modification layer therebetween, and the surface energy for bonding the sheet to the carrier is 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 that is held at a temperature of 600 ° C. for 10 minutes and then cooled to 300 ° C. at 1 ° C. per minute, then the article is removed from the bath and the article is allowed to cool to room temperature. After that, when one is held and the other is exposed to gravity, the carrier and sheet do not separate from each other, there is no outgassing from the surface modification layer during the temperature cycle, and the thinner carrier and sheet are two pieces. There is provided a glass article characterized by the ability to separate the sheet from the carrier without cracking.

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

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

  According to aspect E, 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 2 nm.

  According to any one of aspects F, the support is a glass comprising an alkali-free aluminosilicate or borosilicate or aluminoborosilicate having each of arsenic and antimony at a level of 0.05% by weight or less. Certain glass articles of any one of aspects A through E or 1-20 are provided.

  According to any one of aspects G, there is provided the glass article of any one of aspects A to F or 1 to 20, wherein each of the carrier and the sheet is of a size of 100 mm x 100 mm or more. .

  Hereinafter, preferable embodiments of the present invention will be described in terms of items.

Embodiment 1
A method for controllably bonding a thin sheet to a carrier comprising:
Obtaining a thin sheet having a thin sheet bonding surface;
Obtaining a carrier having a carrier binding surface;
A surface modification layer is deposited on at least one of the thin sheet binding surface and the carrier binding surface to obtain a first surface energy on the one of the thin sheet binding surface and the carrier binding surface. Process,
Treating the surface modified layer to change the first surface energy to a second surface energy greater than the first surface energy; and the thin sheet bonding through the surface modified layer Binding a surface to the carrier binding surface;
A method comprising:

Embodiment 2
The surface modification layer is
Plasma polymerization of a carbon-containing gas to form a layer, followed by treatment of the layer with a nitrogen-containing gas, plasma polymerization,
Plasma polymerization of a carbon-containing gas to form a layer, followed by a first gas that is one of a nitrogen-containing gas and a hydrogen-containing gas, and then a second gas that is the other of the nitrogen-containing gas and the hydrogen-containing gas. Plasma polymerization, in which a continuous treatment of the layer with two gases is performed,
Plasma polymerization of a carbon-containing gas to form a layer, followed by treatment of the layer with an oxygen-containing gas, plasma polymerization,
Plasma polymerization of carbon-containing gas to form a layer, followed by treatment of the layer with nitrogen and oxygen-containing gas, and plasma polymerization of carbon-containing gas to form a layer. Plasma polymerisation, followed by continuous treatment of the layer with a first gas that is a nitrogen and oxygen containing gas and then a second gas that is a nitrogen containing gas,
The method of embodiment 1, wherein the method is deposited and processed by one of

Embodiment 3
The method of embodiment 2, wherein the carbon-containing gas comprises at least one of a hydrocarbon, alkane, alkene, alkyne, or aromatic compound.

Embodiment 4
The carbon-containing gas, methane, ethane, propane, butane, ethylene, propylene, propyne, acetylene, including CO, and of CO ₂ of at least one method of the third embodiment.

Embodiment 5
When a hydrogen-containing gas is used, the hydrogen-containing gas contains H ₂ , and when a nitrogen-containing gas is used, the nitrogen-containing gas is ammonia, N ₂ , hydrazine, N ₂ O, NO, N ₂ O _4. The method of embodiment 2, comprising at least one of methylamine, dimethylamine, trimethylamine, ethylamine, and acetonitrile.

Embodiment 6
When a hydrogen-containing gas is used, the hydrogen-containing gas contains H _{2. When} an oxygen-containing gas is used, the oxygen-containing gas is O ₂ , O ₃ , H ₂ O, methanol, ethanol, propanol, The method of embodiment 2, comprising at least one of N ₂ O, NO, and N ₂ O ₄ .

Embodiment 7
The method of embodiment 2, further comprising flowing hydrogen with the carbon-containing gas during the plasma polymerization.

Embodiment 8
The method of embodiment 2, wherein the carbon-containing gas is fluorocarbon.

Embodiment 9
The method of embodiment 2, wherein the surface modification layer is deposited from a mixture of a polymer-forming gas and a second gas, the second gas being 30% or more of the total mixture.

Embodiment 10
The method of embodiment 9, wherein the second gas is hydrogen.

Embodiment 11
The method of embodiment 9, wherein the second gas comprises an inert gas.

Embodiment 12
The method of embodiment 1, wherein the thin sheet bonded surface comprises glass.

Embodiment 13
The method of embodiment 1, wherein the carrier binding surface comprises glass.

Embodiment 14
14. The method of embodiment 13, wherein the at least one of the thin sheet binding surface and the carrier binding surface has an average surface roughness Ra of 1 nm or less prior to deposition of the surface modified layer.

Embodiment 15
The method of embodiment 14, wherein the at least one of the thin sheet binding surface and the carrier binding surface has an average surface roughness Ra of 1 nm or less after deposition of the surface modification layer and subsequent removal by O ₂ plasma.

Embodiment 16
The carrier binding surface has a first average surface roughness Ra1 prior to the deposition of the surface modification layer, and the carrier is deposited thereon with the surface modification layer and then by O ₂ plasma cleaning. After being removed, having a second surface roughness Ra2, the difference between Ra1 and Ra2 is 1 nm or less, and the measurement of the average surface roughness is performed over an area of 5 × 5 micrometers The method of form 13.

Embodiment 17
The method of embodiment 1, wherein the thickness of the thin sheet is 300 micrometers or less.

Embodiment 18
The method of embodiment 1, wherein the thickness of the surface modification layer is from 1 to 70 nm.

Embodiment 19
The method of embodiment 1, wherein the thickness of the surface modification layer is 2 to 10 nm.

Embodiment 20.
The at least one of the thin sheet bonding surface and the carrier bonding surface comprises glass, and the surface modification layer and its treatment achieve a second surface energy of 41 to 80 mJ / m ² on the bonding surface. The method of any one of Embodiments 1-19.

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 (10)

A method for controllably bonding a thin sheet to a carrier comprising:
Obtaining a thin sheet having a thin sheet bonding surface;
Obtaining a carrier having a carrier binding surface;
A surface modification layer is deposited on at least one of the thin sheet binding surface and the carrier binding surface to obtain a first surface energy on the one of the thin sheet binding surface and the carrier binding surface. Process,
Treating the surface modified layer to change the first surface energy to a second surface energy greater than the first surface energy; and the thin sheet bonding through the surface modified layer Binding a surface to the carrier binding surface;
A method comprising: The surface modification layer is
Plasma polymerization of a carbon-containing gas to form a layer, followed by treatment of the layer with a nitrogen-containing gas, plasma polymerization,
Plasma polymerization of a carbon-containing gas to form a layer, followed by a first gas that is one of a nitrogen-containing gas and a hydrogen-containing gas, and then a second gas that is the other of the nitrogen-containing gas and the hydrogen-containing gas. Plasma polymerization, in which a continuous treatment of the layer with two gases is performed,
Plasma polymerization of a carbon-containing gas to form a layer, followed by treatment of the layer with an oxygen-containing gas, plasma polymerization,
Plasma polymerization of carbon-containing gas to form a layer, followed by treatment of the layer with nitrogen and oxygen-containing gas, and plasma polymerization of carbon-containing gas to form a layer. Plasma polymerisation, followed by continuous treatment of the layer with a first gas that is a nitrogen and oxygen containing gas and then a second gas that is a nitrogen containing gas,
The method of claim 1, wherein the method is deposited and processed by one of the following:   The method of claim 2, further comprising flowing hydrogen with the carbon-containing gas during the plasma polymerization.   The method according to claim 2 or 3, wherein the carbon-containing gas is fluorocarbon.   The method according to any one of claims 2 to 4, wherein the surface modification layer is deposited from a mixture of a polymer-forming gas and a second gas, the second gas being 30% or more of the total mixture.   The method of claim 5, wherein the second gas is hydrogen or comprises an inert gas. The at least one of the thin sheet binding surface and the carrier binding surface has an average surface roughness Ra of 1 nm or less prior to the deposition of the surface modification layer, and the thin sheet binding surface and the carrier binding surface The method according to claim 1, wherein the at least one has an average surface roughness Ra of 1 nm or less after deposition of the surface modification layer and subsequent removal by O ₂ plasma.   The method according to any one of claims 1 to 7, wherein the thickness of the thin sheet is 300 micrometers or less.   The method according to claim 1, wherein the thickness of the surface modification layer is 1 to 70 nm. The at least one of the thin sheet bonding surface and the carrier bonding surface comprises glass, and the surface modification layer and its treatment achieve a second surface energy of 41 to 80 mJ / m ² on the bonding surface. 10. The method according to any one of claims 1 to 9.