JP2015532004A - Flexible glass substrate processing - Google Patents

Abstract

A method of processing a flexible glass substrate is provided. The method includes providing a substrate stack including a flexible glass substrate bonded to a carrier substrate using an inorganic bonding layer that undergoes a structural change upon receiving energy input. An energy input is provided to the inorganic tie layer to initiate the structural change. This structural change reduces the bonding strength of the inorganic bonding layer in order to separate the flexible glass substrate from the carrier substrate.

Description

Explanation of related applications

  This application claims the benefit of the priority of US Provisional Patent Application No. 61/691904, filed Aug. 22, 2012, the contents of which are incorporated herein by reference in their entirety. Claims under Article 119.

  The present invention relates to an apparatus and method for processing a thin substrate on a carrier substrate, and more particularly to a flexible glass thin substrate on a carrier substrate.

  Today, flexible plastic films are commonly used in flexible electronic devices associated with PV, OLED, LCD, touch sensors, flexible electronics, and patterned thin film transistor (TFT) applications.

  Flexible glass substrates have several technical advantages over flexible plastic technology. One technical advantage is the ability of glass to act as a moisture or air barrier, which is a major degradation mechanism in OLED displays, OLED lighting, and organic solar cell devices. A second advantage is its potential to reduce the overall package size (thickness) and weight by reducing or eliminating one or more layers of the package substrate. Other advantages of flexible glass substrates include benefits in light transmission, dimensional stability, thermal capability, and surface quality.

  Since the demand for thinner / flexible glass substrates (thickness less than 0.3 mm) is within the electronic display industry, panel manufacturers have faced several challenges regarding the handling and fitting of thinner / flexible glass substrates. . One option is to process a thicker sheet of glass and then etch or polish the panel to reduce the overall net thickness. This allows the use of an existing panel manufacturing infrastructure based on a substrate with a thickness of 0.3 mm or more, but potentially reduces production and adds finishing costs to the end of the process. The second approach is to redesign existing panel processes for thinner substrates. Loss of glass in the process is a major obstacle, and significant capital is required to minimize handling loss even in sheet-to-sheet processes based on unsupported flexible glass substrates. The third approach uses a technology based on roll-to-roll processing technology or roller handling for a thin flexible glass substrate.

  What is desired is the use of the manufacturer's existing capital infrastructure based on rigid substrates with a thickness of 0.3 mm or more to process thin flexible glass substrates, ie glass with a thickness of about 0.3 mm or less. It is a transportation approach that enables

  The concept of the present invention is to bond a thin sheet, for example, a flexible glass substrate, to a carrier substrate using an inorganic bonding layer that changes its structure upon receiving energy input such as thermal energy. This structural change reduces the bonding strength of the inorganic bonding layer in order to separate the flexible glass substrate from the carrier substrate.

  One commercial advantage of this approach is that manufacturers can take advantage of existing capital investments in processing facilities, while at the same time, for example, PV, OLED, LCD, touch sensors, flexible electronics, and patterned thin film transistors (TFTs). ) Benefits of thin glass sheets for electronics.

According to the first aspect, the method of processing a flexible glass substrate comprises:
Providing a substrate laminate comprising a flexible glass substrate bonded to a carrier substrate using an inorganic bonding layer that undergoes a structural change upon receiving energy input; and
Providing energy input to the inorganic bonding layer to initiate a structural change that reduces the bonding strength of the inorganic bonding layer to separate the flexible glass substrate from the carrier substrate;
including.

  According to a second aspect, there is provided the method of aspect 1, comprising the step of heating the inorganic tie layer to a temperature of at least about 250 ° C., wherein the energy input is thermal energy.

  According to a third aspect, there is provided the method of aspect 1 or 2, wherein the energy input is light energy that provides heating of the inorganic tie layer to at least about 250 ° C.

  According to the fourth aspect, there is provided the method according to any one of aspects 1 to 3, wherein the inorganic bonding layer includes an inorganic bonding material positioned along the outer periphery of the flexible glass substrate.

  According to a fifth aspect, there is provided the method of any one of aspects 1 to 4, wherein the inorganic tie layer is locally heated using a laser.

  According to a sixth aspect, there is provided the method of any one of aspects 1 to 5, wherein the structural change comprises crystallization.

  According to a seventh aspect, there is provided the method of any one of aspects 1 to 6, wherein the structural change includes an increase in porosity of the inorganic tie layer.

  According to an eighth aspect, there is provided the method of any one of aspects 1 to 7, wherein the structural change comprises an increase in microfracture of the inorganic tie layer.

  According to a ninth aspect, there is provided the method of any one of aspects 1 to 8, further comprising the step of removing the flexible glass substrate from the carrier substrate after providing energy input to the inorganic tie layer.

  According to a tenth aspect, there is provided the method of any one of aspects 1 to 9, further comprising applying an electrical component to the flexible glass substrate.

  According to an eleventh aspect, there is provided the method according to any one of aspects 1 to 10, wherein the thickness of the flexible glass substrate is about 0.3 mm or less.

  According to a twelfth aspect, there is provided the method of any one of aspects 1 to 11, wherein the carrier substrate comprises glass.

  According to a thirteenth aspect, there is provided the method of any one of aspects 1-12, wherein the bonding material comprises one or more of glass, glass ceramic, and ceramic.

  According to a fourteenth aspect, there is provided the method of any one of aspects 1 to 13, wherein the binding material comprises carbon.

  According to a fifteenth aspect, there is provided the method of any one of aspects 1 to 14, wherein the bonding material comprises silicon.

  According to a sixteenth aspect, there is provided the method of any one of aspects 1-15, comprising at least partially peeling the flexible glass substrate and the carrier substrate when the structure of the bonding material is changed. .

  According to a seventeenth aspect, the method of any one of aspects 1-16, wherein the input energy is thermal energy and the bonding material comprises heating to a temperature of at least about 250 ° C. without reducing bond strength. Is provided.

  According to an eighteenth aspect, the method of any one of aspects 1-17, wherein the input energy is light energy and the step of heating the bonding material to a temperature of at least about 250 ° C. without reducing the bonding strength. Is provided.

According to a nineteenth aspect, a method for processing a flexible glass substrate comprises:
Providing a carrier substrate having a glass support surface;
Providing a flexible glass substrate having a first wide surface and a second wide surface;
Bonding the first wide surface of the flexible glass substrate to the glass support surface of the carrier substrate using an inorganic bonding layer; and
Reducing the bond strength between the flexible glass substrate and the carrier substrate by changing the structure of the inorganic bonding layer to remove the flexible glass substrate from the carrier substrate;
including.

  According to a twentieth aspect, the aspect 19 includes providing energy input to the inorganic bonding layer to change the structure of the inorganic bonding layer to reduce the bonding strength between the flexible glass substrate and the carrier substrate. A method is provided.

  According to a twenty-first aspect, there is provided the method of aspect 20, comprising the step of heating the inorganic tie layer to a temperature of at least about 250 ° C., wherein the energy input is thermal energy.

  According to a twenty-second aspect, there is provided the method of aspect 20 or 21, comprising the step of heating the inorganic tie layer to a temperature of at least about 250 ° C., wherein the energy input is light energy.

  According to a twenty-third aspect, there is provided the method of any one of aspects 19 to 22, wherein the inorganic tie layer is locally heated using a laser.

  According to a twenty-fourth aspect, there is provided the method of any one of aspects 19-23, wherein the inorganic tie layer is heated using a flash lamp.

  According to a twenty-fifth aspect, there is provided the method of any one of aspects 19-24, wherein the flexible glass substrate has a thickness of about 0.3 mm or less.

According to a twenty-sixth aspect, the substrate laminate is
A carrier substrate having a glass support surface;
A flexible glass substrate supported by the glass support surface of the carrier substrate, and
An inorganic bonding layer for bonding a flexible glass substrate to a carrier substrate, including a bonding material for changing the structure and reducing the bonding strength between the flexible glass substrate and the carrier substrate for removing the flexible glass substrate from the carrier substrate , Inorganic binding layer,
It has.

  According to a twenty-seventh aspect, there is provided the substrate laminate of aspect 26, wherein the binding material includes carbon.

  According to a twenty-eighth aspect, there is provided the substrate laminate of aspect 26 or 27, wherein the bonding material comprises silicon.

  According to a twenty-ninth aspect, there is provided the substrate laminate of aspect 26, wherein the bonding material comprises at least one of glass, glass ceramic, and ceramic.

  According to a thirtieth aspect, there is provided the substrate laminate of aspect 26, wherein the bonding material comprises amorphous silicon.

  According to a thirty-first aspect, there is provided the substrate laminate according to any one of aspects 26 to 30, wherein the structural change includes crystallization.

  According to a thirty-second aspect, there is provided the substrate laminate according to any one of aspects 26 to 31, wherein the flexible glass substrate has a thickness of about 0.3 mm or less.

  Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from the description, or as illustrated in the written description and accompanying drawings, It will also be appreciated by practice of the invention as defined in the appended claims. The foregoing general description and the following detailed description are merely exemplary of the invention and are intended to provide an overview or arrangement for understanding the nature and features of the claimed invention. Please understand that.

  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 operations of the invention using examples. It should be understood that the various features of the invention disclosed in this specification and the drawings can be used in any combination and all combinations.

Side view of one embodiment of a substrate stack including a flexible glass substrate supported by a carrier substrate 1 is an exploded perspective view of the substrate laminate of FIG. The figure which showed one Embodiment of the method of processing the flexible glass substrate and board | substrate laminated body of FIG. Top view of one embodiment of a substrate stack including flexible glass substrates and carrier substrates having different sizes Top view of another embodiment of a substrate stack comprising a flexible glass substrate and a carrier substrate having different shapes Top view of one embodiment of a substrate stack including a bonding layer applied on a glass support surface of a carrier substrate Top view of another embodiment of a substrate stack including a bonding layer applied on a glass support surface of a carrier substrate Top view of another embodiment of a substrate stack including a bonding layer applied on a glass support surface of a carrier substrate Diagram showing X-ray diffraction data at room temperature for the bonding layer Diagram showing X-ray diffraction data at 180 ° C. for the bonding layer of FIG. FIG. 9 shows X-ray diffraction data at 250 ° C. for the bonding layer of FIG. Diagram showing the absorbance of a carbon-based bonding layer The figure which showed one Embodiment of the method of processing the board | substrate laminated body containing an amorphous silicon bond layer Diagram showing the process of applying thermal energy to the bonding layer through a flexible glass substrate Diagram showing the process of applying thermal energy to the bonding layer through the carrier substrate FIG. 6 illustrates another embodiment of a method for processing a substrate stack including an amorphous silicon bonding layer. FIG. 6 illustrates another embodiment of a method for processing a substrate stack including an amorphous silicon bonding layer. Top view of one embodiment of a substrate stack including a bonding layer applied on a glass support surface of a carrier substrate Top view of one embodiment of a substrate stack for forming a plurality of desired portions The figure which showed one Embodiment of the method of releasing a flexible glass substrate from a carrier substrate

  Embodiments described herein generally relate to the processing of flexible glass substrates, sometimes referred to herein as device substrates. The flexible glass substrate can be part of a substrate stack that generally includes a carrier substrate and a flexible glass substrate bonded to the carrier substrate by an inorganic bonding layer. As used herein, the term “inorganic material” refers to a compound that is not a hydrocarbon or a derivative thereof. As will be described in more detail below, this bonding layer undergoes a structural change upon receiving energy input. When the bonding layer receives energy input, this structural change reduces the bonding strength of the bonding layer, or otherwise, in order to more easily separate the flexible glass substrate from the carrier substrate than before energy input. Change.

  Referring to FIGS. 1 and 2, the substrate laminate 10 includes a carrier substrate 12 and a flexible glass substrate 20. The carrier substrate 12 has a glass support surface 14, an opposing support surface 16, and an outer edge 18. The flexible glass substrate 20 has a first wide surface 22, an opposing second wide surface 24, and an outer edge 26. The thickness 28 of the flexible glass substrate 20 is not limited, but is about 0.01 to 0.05 mm, about 0.05 to 0.1 mm, about 0.1 to 0.15 mm, and about 0.15, for example. It may be “ultra-thin” of about 0.3 mm or less, such as a thickness of ˜0.3 mm.

  The flexible glass substrate 20 is bonded to the glass support surface 14 of the carrier substrate 12 using the bonding layer 30 at the first wide surface 22. The tie layer may be an inorganic tie layer containing an inorganic tie material. When the carrier substrate 12 and the flexible glass substrate 20 are bonded to each other by the bonding layer 30, the combined substrate laminate 10 has a thickness 25 that is a single glass that is thicker than the single flexible glass substrate 20. It can be the same as the substrate, which can be suitable for use with existing device processing infrastructure. For example, when the processing facility of the device processing infrastructure is designed for a 0.7 mm sheet and the thickness 28 of the flexible glass substrate 20 is 0.3 mm, the thickness 32 of the carrier substrate 12 is, for example, that of the bonding layer 30. Depending on the thickness, it can be chosen to be anything below 0.4 mm.

  The carrier substrate 12 may be of any suitable material, including glass, glass ceramic, or ceramic, by way of example, and may or may not be transparent. When made from glass, the carrier substrate 12 may be of any suitable composition, including aluminosilicate, borosilicate, aluminoborosilicate, soda lime silicate, and for its end use. Depending on the case, it may be one containing an alkali or one containing no alkali. The thickness 32 of the carrier substrate 12 is about 0.2 to 3 mm, for example, 0.2, 0.3, 0.4, 0.5, 0.6, 0.65, 0.7, 1.0, It may be 2.0 or 3 mm, and may depend on the thickness 28 of the flexible glass substrate 20 as described above. Further, the carrier substrate 12 may be made from a single layer as shown, or may be a plurality of layers (multiple thin sheets formed together) joined together to form part of the substrate stack 10. It may be produced from (including).

  The flexible glass substrate 20 may be formed from any suitable material, including glass, glass ceramic, or ceramic, by way of example, and may or may not be transparent. The flexible glass substrate 20, when made from glass, may be of any suitable composition, including aluminosilicate, borosilicate, aluminoborosilicate, soda lime silicate, and its end use Depending on the case, it may be one containing an alkali or one containing no alkali. The thickness 28 of the flexible glass substrate 20 may be about 0.3 mm or less, such as about 0.2 mm or less or about 0.1 mm as described above. As described herein, the flexible glass substrate 20 may be the same size and / or shape as the carrier substrate 12 or may be of a different size and / or shape.

  Referring to FIG. 3, a releasable bonding method 40 is shown as part of the processing of the flexible glass substrate 20. In step 42, the carrier substrate 12 and flexible glass substrate 20 are selected based on, for example, their size, thickness, material, and / or end use. Once the carrier substrate 12 and the flexible glass substrate 20 are selected, a bonding layer 30 may be applied to one or both of the glass support surface 14 and the first wide surface 22 of the flexible glass substrate 20 at step 44. The bonding layer 30 may be applied by any suitable method such as pressure application using a nozzle or the like, spreading, dissolution, spin casting, spraying, dipping, vacuum or deposition in the air, or the like. Can be used.

  In step 46, the flexible glass substrate 20 is bonded to the carrier substrate 12 by bonding or otherwise using the bonding layer 30. In order to obtain a desired bonding strength between the flexible glass substrate 20 and the carrier substrate 12, the bonding material forming the bonding layer 30 is heated, cooled, dried, mixed with other materials, reaction induction, pressure application Etc. may be performed. As used herein, “bond strength” refers to any one or more of dynamic shear strength, dynamic peel strength, static shear strength, static peel strength, and combinations thereof. Peel strength, for example, initiates damage (static) using stress applied to one or both of the flexible glass substrate and the carrier substrate in a peel mode and / or maintains a specific damage rate This is the force per unit width required for (dynamic). Shear strength refers to initiating damage using stress applied to one or both of the flexible glass substrate and the carrier substrate in shear mode (static) and / or maintaining a specific damage rate (dynamic) This is the force per unit width required for Since any change in bond strength is a comparison of bond strength measured before and after the desired energy input to the bond layer 30, any suitable method may be used, including any suitable peel strength test and / or shear strength test. Thus, the bond strength can be determined.

  Steps 48 and 50 relate to releasing or peeling the flexible glass substrate 20 from the carrier substrate 12 so that the flexible glass substrate 20 can be removed from the carrier substrate 12. Before and / or after releasing the flexible glass substrate 20 from the carrier substrate 12, the flexible glass substrate 20 can be, for example, a display device such as an LCD, OLED, or TFT electronics, or other electronic device such as a touch sensor or solar cell. Can be processed in the formation process. For example, an electrical component or a color filter may be applied to the second wide surface 24 (FIGS. 1 and 2) of the flexible glass substrate 20. Further, the final electronic component may be assembled or combined with the flexible glass substrate 20 before releasing the flexible glass substrate 20 from the carrier substrate 12. For example, an additional film or glass substrate may be laminated to the surface of the flexible glass substrate 20, or an electrical component such as a flex circuit or IC may be bonded. Once the flexible glass substrate is processed, an energy input 47 that changes the structure of the bonding layer 30 may be applied to the bonding layer 30 at step 48. As will be described below, this structural change reduces the bond strength of the bonding layer 30 and facilitates the separation of the flexible glass substrate 20 from the carrier substrate 12 as compared to before energy input in step 48. In step 50, the flexible glass substrate 20 is removed from the carrier substrate 12. For example, this removal can be achieved by peeling the flexible glass substrate 20 or a portion of the flexible glass substrate 20 from the carrier substrate 12. The peel force is generated by applying a force F to one or both of these substrates at an angle to a plane P that extends through the bonding layer 30.

Selection of Carrier Substrate and Flexible Glass Sheet Carrier substrate 12 and flexible glass substrate 20 can be formed from the same material, similar materials, or different materials. In some embodiments, the carrier substrate 12 and the flexible glass substrate 20 are formed from glass, glass ceramic, or a ceramic material. The carrier substrate 12 and the flexible glass substrate 20 can be formed using the same molding process, or a similar molding process, or different molding processes. For example, a fusion process (such as a downdraw process) forms a high quality thin glass sheet that can be used in various devices such as flat panel displays. If different materials are used, it may be desirable for the values of the coefficients of thermal expansion to match. The surface of the glass sheet produced | generated by a fusion process has the outstanding flatness and smoothness compared with the glass sheet produced | generated by another method. This fusion process is described in US Pat. Nos. 3,338,696 and 3,682,609. Other suitable glass sheet forming methods include the float process, the redraw process, and the slot draw method. The flexible glass substrate 20 (and / or the carrier substrate 12) has a temporary or permanent protective layer or other type on one or both of the first wide surface 22 and the second wide surface 24. The coating layer may further be included.

  One or more of the dimensions and / or shapes of the carrier substrate 12 and the flexible glass substrate 20 may be substantially the same and / or different. For example, referring briefly to FIG. 4, the illustrated carrier substrate 12 has substantially the same shape as the flexible glass substrate 20, but has one or more dimensions larger than the flexible glass substrate 20. With such an arrangement, the peripheral area 52 of the carrier substrate 12 can extend outwardly beyond the flexible glass substrate 20 around all or at least a portion of the outer edge 26 of the flexible glass substrate 20. As another example, FIG. 5 shows an embodiment in which the flexible glass substrate 20 has a different shape and different dimensions than the carrier substrate 12. With such an arrangement, only some portions 54 of the outer edge 18 of the carrier substrate 12 can extend beyond the outer edge 26 of the flexible glass substrate 20. Although rectangular and circular shapes are illustrated, any suitable shape, including irregular shapes, can be used depending on the desired laminate configuration. Furthermore, the edges of the carrier substrate 12 may be rounded, finished and / or ground to withstand impact and to aid handling. Surface properties such as grooves and / or holes may be further provided to the carrier substrate 12. Grooves, holes, and / or other surface characteristics may promote and / or inhibit binding material positioning and / or adhesion.

Bonding Layer Selection and Application Bonding layer 30 may include one or more bonding materials that undergo a structural change upon receipt of energy input. For example, the bonding layer 30 can include inorganic materials and can include materials such as glass, glass ceramic, ceramic, and carbon-containing materials. In some embodiments, the tie layer 30 is made of carbon and may form a carbon tie layer. In some embodiments, the bonding layer 30 is made of silicon and may form a silicon bonding layer. Various exemplary bonding materials are described below. The bonding layer 30 may be applied by any suitable method such as pressure application using a nozzle or the like, spreading, dissolution, spin casting, spraying, dipping, vacuum or deposition in the air, or the like. Can be used.

The tie layer 30 may be applied in any suitable pattern and / or shape. Referring to FIG. 6, a bonding layer 30 is applied over area A ₁ of glass support surface 14, which is at least about 50 of area A ₂ , such as substantially all of area A ₂ covered by flexible glass substrate 20. Percent. In some embodiments, A ₁ is such as about 25 percent or less of A _2, may be less than about 50% of A _2. The bonding layer 30 may extend beyond the outer periphery of the flexible glass substrate 20 or may be included inside the outer periphery of the flexible glass substrate 20. Referring to FIG. 7, the tie layer 30 is continuously applied along a predetermined path, such as an area A ₃ that extends around the outer edge of A ₂ (ie, continuous perimeter bond) and is surrounded by the tie layer 30. The unbonded region R may be left. Referring to FIG. 8, the bonding layer 30 may be formed from discontinuous bonding segments 60 spaced from one another. In the embodiment of FIG. 8, the discontinuous connecting segments are in the form of individual lines. Any other suitable shape may be used, such as circles, dots, random shapes, and combinations of various shapes.

Changing the structure of the tie layer An energy input is provided to the tie layer 30 that is used to change the structure of the tie layer 30 or to change the structure of the tie layer 30. This structural change reduces the bonding strength of the bonding layer 30 compared to before energy input, and helps to separate the flexible glass substrate 20 from the carrier substrate 12. The bond strength can be reduced by reducing the cohesive strength of the bond layer 30 itself and / or the bond strength between the bond layer 30 and / or the flexible glass substrate 20 and the carrier substrate 12. The type of energy input depends at least in part on the bonding material used for the bonding layer 30. Non-limiting examples of binding materials and input energies used to create the tie layer 30 are described below, but are not intended to be limiting. The first few examples show crystallizing the bonding layer 30 with the input of energy, which reduces the bonding strength of the bonding layer 30. Such a decrease in bond strength helps to separate the flexible glass substrate 20 from the carrier substrate 12 without damaging the flexible glass substrate 20.

Bismuth zinc borate (BZB) glass was formed and ground to an average particle size of less than 20 microns. BZB glass particles were passed through a 350 mesh screen and mixed with the binder at 75 ° C. at 100 ° C. in a helicone mixer. The thermally heated paste was pipetted onto the carrier substrate, and a bonding layer was formed on the carrier substrate using a doctor blade. Bonding layers were formed with approximate thicknesses of 25 μm, 75 μm, and 125 μm for evaluation. The thickness can be further reduced by using a smaller glass particle size or by a film forming method for forming a bonding layer. After forming the tie layer, the following thermal profile was applied:
a. From room temperature to 200 ° C. at 5 ° C./min;
b. Hold at 200 ° C. for 1 hour to burn off the binder;
c. From 200 ° C. to 400 ° C. at 5 ° C./min;
d. Hold at 400 ° C. for 1 hour;
e. cooling.
X-ray diffraction showed crystallization of bismuth oxide, bismuth borate, zinc oxide, and boron oxide in the tie layer due at least in part to the thermal gradient and the particle size of the BZB glass particles. This crystallization reduces the bond strength provided by the tie layer.

Phosphate glass powder was prepared by grinding and passing through a 325 mesh screen. The phosphate glass powder was then mixed with C18 binder at 83% by weight. The heated paste was applied to the substrate using a doctor blade to produce approximate evaluation thicknesses of 25 μm and 75 μm. The thickness can be further reduced by using a smaller glass particle size or by a film forming method for forming a bonding layer. After forming the tie layer, the following thermal profile was applied:
a. From room temperature to 200 ° C. at 1 ° C./min;
b. Hold at 200 ° C. for 1 hour;
c. From 200 ° C. to 400 ° C. at 1 ° C./min;
d. Hold at 400 ° C. for 1 hour;
e. cooling.
X-ray crystallization of barium oxide, zinc phosphate, zinc phosphide, zinc oxide, and barium zinc phosphide in the tie layer due at least in part to the thermal profile and particle size of the phosphate glass particles Shown by diffraction. This crystallization reduces the bond strength provided by the tie layer.

Small chunks of tin fluorophosphate glass are made from two EAGLE2000® brand (non-alkali) 0.7 mm thick commercially available from Corning Incorporated, Corning, NY Aluminoborosilicate glass) between the substrates. This laminate was placed in an oven with a weight on top to provide a bonding force. Six different thermal profiles were used to determine the temporary bonding and debonding of these substrates. All the temperature increases to 5 ° C / min were performed:
1. The laminate was heated to a maximum temperature of 150 ° C. There were no visible signs of phosphate glass dissolution or binding;
2. The laminate was heated to a maximum temperature of 160 ° C. There were no visible signs of phosphate glass dissolution or binding;
3. The laminate was heated to a maximum temperature of 170 ° C. Bonding between the substrates of EAGLE2000-phosphate glass-EAGLE2000 was observed and there were no obvious signs of crystallization in the bonding layer;
4). The laminate was heated to a maximum temperature of 200 ° C. Possible signs of crystallization in the tie layer;
5. When the laminate was heated to a maximum temperature of 180 ° C., bonding between the substrates of EAGLE2000-phosphate glass-EAGLE2000 was observed, and there was no sign of crystallization visible in the bonding layer. The laminate was then heated to a maximum temperature of 400 ° C. with signs of crystallization throughout the tie layer, along with changes in the mechanical properties and density of the tie layer;
6). When the laminate was heated to a maximum temperature of 180 ° C., bonding between the substrates of EAGLE2000-phosphate glass-EAGLE2000 was observed, and there was no sign of crystallization visible in the bonding layer. The laminate was then heated to a maximum temperature of 250 ° C., where signs of crystallization were observed, but less than the crystallization observed at 400 ° C. Thereafter, the EAGLE 2000 substrate was separated.

The above examples show that a glass substrate can be bonded together using a bonding layer of inorganic material. After a certain manufacturing step, the tie layer can be heated to even higher temperatures to induce crystallization and / or other structural changes in the tie layer. This structural change allows the glass substrate to be separated with less force than before the structural change occurs in the bonding layer. FIGS. 9, 10 and 11 show the bonding layer 30 of Example 3 exposed to higher temperatures. Shows crystallization. FIG. 9 shows the phosphate glass bond layer at the time of formation, FIG. 10 shows the phosphate glass bond layer at 180 ° C., and FIG. 11 shows the phosphate glass bond layer at 250 ° C. Comparing FIGS. 9 and 10, it can be seen that there was some crystallization in the phosphate glass during formation and at 180 ° C. FIG. 11 shows that there is a significantly higher level of crystallization in the phosphate glass at 250 ° C., which reduces bond strength and delamination of the flexible glass substrate when the separation force is applied. Improve. This indicates that the two substrates are bonded together and they can withstand the thermal process. The flexible glass substrate 20 can then be peeled from the carrier substrate 12 after the bonding layer 30 is crystallized.

  Note that optimization of the bonding material should be made for the specific equipment manufacturing process used. For example, a-Si or p-Si TFT processes where the manufacturing temperature is about 250 ° C. or higher, eg, about 350 ° C. or higher, between about 250 ° C. to about 600 ° C., reduces any possibility of unintended stripping. For this purpose, a bonding material can be selected whose thermal exposure during peeling exceeds 250 ° C. or higher, for example 350 ° C. or higher, 600 ° C. or higher. However, the thermal exposure to the device or other component being manufactured should be selected to be less than anything that can damage any device electronics or other component. In some embodiments, the bond strength of the bond layer 30 does not substantially decrease or hardly decreases until the target is exposed to exfoliation heat (eg, less than about 25 percent, less than about 10 percent, less than about 5 percent, For example, less than about 50 percent). Thus, the release material can be optimized for various device manufacturing situations. Furthermore, the energy 47 may be applied locally to the bonding layer 30 itself. For example, the energy source is optimized so that the bonding layer 30 absorbs most of the energy 47, thereby lowering the thermal impact on the flexible substrate 20, the carrier substrate 12, or any device layer on the flexible substrate 20. can do.

In this example, a glass binder composition of 80 mol% SnO and 20 mol% P ₂ O ₅ was used. A plurality of these glass pieces were placed between two 5 cm × 5 cm samples of EAGLE XG® (an alkali-free aluminoborosilicate glass available from Corning, Corning, NY). Thereafter, various samples were subjected to thermal cycling to determine the temperature at which the glass was bonded to EAGLE XG and the temperature at which the ABR glass was crystallized.

  As a first test, a laminate of EAGLE XG and a binding material was placed in a furnace with a 375 g weight on top. The furnace was heated at 5 ° C./min to 320 ° C., held for 1 hour, and then cooled. It was observed that the binding material was dissolved and bound to the EAGLE XG substrate. The binding material remained optically clear. However, the bonding material adhered to only one of the two EAGLE XG substrates, possibly due to thermal expansion mismatch. In actual implementation, the bonding material may be adjusted so that the CTE matches the display glass substrate.

  As a second test, a sample laminate similar to the above example was assembled and then heat cycled to 350 ° C. This resulted in the bonding material crystallizing and optically scattering. In this case, the binding material agglomerated therein and failed to function, and the EAGLE XG glass easily separated.

These tests on binding materials demonstrate that it is possible to adhere an inorganic adhesive to the display glass and subsequently cause crystallization at higher temperatures. As an example of one predictive situation, consider the following:
A. Bonding the display glass substrate to the processing carrier at a temperature above the temperature at which the device is assembled (eg, 320 ° C.);
B. Assembling the display device at a temperature below the bonding temperature (<320 ° C.);
C. The bonding material is crystallized to reduce adhesion between the substrate glass and the carrier. For example, this will occur at temperatures above the bonding temperature (eg 350 ° C.). If the manufactured device cannot withstand this temperature, the bonded glass may be differentially heated using local laser exposure or other absorbed energy;
D. Further, the display glass substrate is separated from the processing carrier.

A thin SiO ₂ bonding layer was formed using a hydrogen silsesquioxane solution such as Fox-25 available from Dow Corning. The procedure for manufacturing the laminate included the following:
a. A glass carrier substrate (EAGLE2000) having a size of 5 cm × 5 cm and a thickness of 0.7 mm was used;
b. A hydrogen silsesquioxane solution was spin-cast on a carrier substrate at 300 rpm for 15 seconds to form a bonding layer. For larger scale applications, other liquid dispensing and film forming methods may be possible;
c. The device substrate was applied to the bonding layer before the bonding layer dried. The device substrate had the same configuration as the carrier substrate;
d. The laminate was placed on a hot plate at room temperature with a weight on top to give a maximum bonding pressure of 100 kPa;
e. The hot plate was heated to 175 ° C. and held for 5-15 minutes, then heated for 5-15 minutes to reach 250 ° C .;
f. The hot plate temperature was lowered to 175 ° C. and held for 5 minutes. This initial thermal cycle used to remove the solvent was found to have a significant effect on bond strength.

  The process of Example 5 can produce a high shear strength bond between the carrier substrate and the device substrate. It has been found that it is relatively difficult to separate the device substrate from the carrier substrate by applying a shear force using two pieces of tape on each of the carrier substrate and the device substrate. However, it was relatively easy to separate the device substrate from the carrier substrate by applying a peeling force. A further reduction in strength was achieved by heating the tie layer to above 350 ° C.

  Changes in the structure of the tie layer include changes other than crystallization, such as those that induce a change in the volume of the bond material, those that induce a change in the density of the bond material, those that induce microfracture in the bond layer, and the bond material Can induce cohesive failure in the core, and can increase the etching sensitivity of the binding material. Although one or more of the above-described bonding materials exhibit crystallization and / or other structural changes in the bonding layer, other materials can be used to form the bonding layer. For example, if a bonding layer containing carbon is used, the flexible glass substrate and the carrier substrate can be releasably bonded.

A tie layer containing carbon was formed from a phenolic resin solution. This process utilized phenol formaldehyde copolymers and produced samples by spin casting and thermal curing processes. The process steps included:
a. A diluted phenolic resin solution of 70% by weight resin and 30% by weight DI water was spin-cast on a carrier substrate at 3 krpm for 30 seconds to obtain a bonding layer having a thickness of 10 μm or less;
b. The carrier substrate with the bonding layer and the device substrate placed thereon were placed on a hot plate at room temperature. A weight was applied that produced a maximum binding pressure in excess of 100 kPa;
c. The hot plate was heated to 150 ° C. and held for about 10 minutes, then cooled to room temperature;
d. The laminate was circulated in air in the furnace for 1 hour until reaching 400 ° C., and then cooled.

  This process was used to bond the device substrate to the carrier substrate. This withstood the shear tensile test, but separated from the carbon bond layer left after heating and the peeling force applied due to at least some increase in porosity formed in the bond layer during heating. was there. Both the device substrate and the carrier substrate were formed from 0.7 mm thick EAGLE 2000 (8 cm × 12 cm) substrates.

  Further screening tests were performed on the laminate formed according to Example 6. These laminates were circulated in air in a furnace at 500 ° C. for 1 hour to cause violent oxidation in the bonding layer. This oxidation of the carbon bonding layer can be used to peel the device substrate from the carrier substrate. Since the oxidized carbon evaporates, the carbon bond layer can be easily removed and the carrier substrate can be cleaned for reuse.

  The bond strength between the flexible glass substrate 20 and the carrier substrate 12 can be reduced by oxidizing the carbon-based bond layer. As in the fifth embodiment, carbon can be oxidized by heating the bonding layer 30 to a temperature of about 500 ° C. in the presence of oxygen. In the presence of ozone, oxidation of the carbon bonded layer can occur at temperatures below 500 ° C. Heating the fully assembled device substrate to 500 ° C. is not acceptable in some embodiments, but the bonding layer may be heated to a temperature that requires local laser oxidation.

  Referring to FIG. 12, the absorbance of the carbon-based bonding layer 30 is shown. A laser may be used to locally heat and oxidize the carbon-based bonding layer 30 (or any one or more bonding materials described herein). In order to assist local heating of the carbon-based bonding layer 30 by the laser, the carbon-based bonding layer 30 may be applied as an outer peripheral bond (FIG. 7), and the carbon-based bonding layer 30 is close to the outer periphery of the flexible glass substrate 20. By being, it can approach the carbon base coupling layer 30 more. FIG. 12 shows an absorption spectrum for the carbon-based bonding layer 30 obtained from the phenolic resin described in Example 6 above. As can be seen, the absorbance increases in the visible and UV spectra, allowing heating of the binding material useful for thermal oxidation. A dopant may be added to the tie layer to increase the amount of radiation absorbed.

  In laser heating or other heating methods targeted primarily at energy absorption in the coupling layer 30, the energy source should be adjusted to the absorption spectrum of the coupling layer. In this case, laser or other energy is applied through the flexible glass substrate 20 or the carrier substrate 12. The flexible glass substrate 20 or the carrier substrate 12 can at least partially transmit this energy. Most of the energy passes through the flexible glass substrate 20 or the carrier substrate 12 and is then absorbed by the bonding layer 30. In the case of the carbon-based film spectrum shown in FIG. 12, this can be achieved by using a red, green, blue, or UV light source. Lasers, LEDs, and flash lamps are examples of light sources. The spectrum of FIG. 12 shows strong absorption at wavelengths below 700 nm. Comparing the absorption of typical glass carriers and carbon-based films, exposure wavelengths in the range of 400 nm to 550 nm can be most efficient.

As indicated above, the bonding material used to form the bonding layer 30 may be selected based on the particular device manufacturing situation. In order to demonstrate the suitability of the bonding layer 30 in the SiTFT manufacturing process, the following steps are performed on an 8 cm × 12 cm carrier substrate and device substrate formed from a bonded EAGLE 2000 substrate as described in Example 4. went. After each step, the shear strength was tested by attempting to pull the device substrate from the carrier substrate in the plane of the bonding layer. All laminate samples withstood the shear stress test and could be more easily peeled off after the last 400 ° C. furnace cycle. To make this evaluation, the substrates were bonded together in a staggered configuration so that the unbonded portions of the substrate could assist in the shear test and peel test. The screening process included:
1. Immerse in DI water at room temperature, dry with N ₂ gun blow, dry completely on hot plate at 100 ° C for 5 minutes
2. Soak in concentrated photoresist developer for 5 minutes, rinse with DI water, N ₂ gun blow dry, and dry on 100 ° C. hot plate for 5 minutes;
3. Immerse in chrome etchant for 5 minutes, rinse with DI water, N ₂ gun blow dry, and dry on 100 ° C. hot plate for 5 minutes;
4). Immerse in gold etchant for 5 minutes, rinse with DI water, dry with N ₂ gun blow, and dry on 100 ° C. hot plate for 5 minutes;
5. Soak in DI water at 95-100 ° C. for 15 minutes, N ₂ gun blow dry, and dry on 100 ° C. hot plate for 5 minutes;
6). Furnace cycle, hold in air at 400 ° C. for 1 hour.

  In still other embodiments, the bonding layer 30 may be formed from amorphous silicon, and the flexible glass substrate 12 may be bonded to the carrier substrate 20 using anodic bonding. Amorphous silicon can be deposited on one or both of the flexible glass substrate 12 and the carrier substrate 20. An electrical bias may be applied across the substrate stack (FIG. 1), resulting in a concentrated oxygen layer at the contact surface between the bonding layer 30 and the flexible glass substrate 12 and carrier substrate 20, which is silica. An amorphous silica bonding layer that reacts with and bonds the flexible glass substrate 12 and the carrier substrate 20 may be formed. For bonding, heat and / or pressure may or may not be used. For example, when no pressure is applied, the flexible glass substrate 12 is amorphous silicon on the carrier substrate 12 at a temperature (eg, less than 500 ° C.) lower than the temperature (eg, greater than 700 ° C.) when the pressure is applied. Can be combined. In some embodiments, it may be desirable to suppress any warping or other potential defects that may occur in the flexible glass substrate 20 at higher temperatures by using a relatively low temperature.

  Similar to the above, the bonding strength of the bonding layer 30 formed of amorphous silicon can be reduced by energy input. The energy applied to the bonding layer 30 can change the amorphous silicon into polycrystalline silicon or a molten structure, and the flexible glass substrate 20 can be peeled off from the carrier substrate 12 by utilizing the change characteristics of the material.

  Referring to FIG. 13, the laser 200 may provide a laser beam 202 that is used to heat the bonding layer 30 formed from amorphous silicon that bonds the flexible glass substrate 12 and the carrier substrate 20. Laser crystallization, which can utilize high intensity laser pulses, may be used to heat the amorphous silicon until the melting point is exceeded. In some cases, melting of the bonding layer 30 may only be required in part, for example at the contact surface between the bonding layer 30 and the flexible glass substrate 20 and / or the carrier substrate 20. The molten silicon can then crystallize upon cooling and deform the topography 204 of the bonding layer 30 to aid in the release of the flexible glass substrate 12. In some embodiments, the topography 204 of the bonding layer 30 can cause the bonding layer 30 to have an area where force is applied and an area that expands, thereby separating the flexible glass substrate 20 from the carrier substrate 12. .

Any suitable laser energy can be utilized for dissolution and / or removal of silicon. In HeNe laser 633nm as an example, it is not possible to dissolve the silicon surface at a fluence of less than 0.8 J / cm ^2, the laser ablation of silicon may occur at higher fluence greater than 2J / cm ^2. A laser pulse with a duration of 20 ns and a fluence of 1.6 J / cm ² fully dissolves the silicon surface without ablation. Other suitable lasers include UV lasers due to the high absorption of silicon. For example, in a XeCl laser 308 nm, silicon can be removed using a 30 ns pulse with a fluence between about 2 and 52 J / cm ² . As another example, in an ArF laser, silicon can be removed using a 12 ns pulse with a fluence greater than 1 J / cm ² . A laser beam is provided to the bonding layer 30 through the carrier substrate 12 (FIG. 14A), through the flexible glass substrate 20 (FIG. 14B), and / or between the carrier substrate 12 and the flexible glass substrate 20 (ie, from the side). May be.

  Referring to FIG. 15, the laser 200 may provide a laser beam 202 that is used to remove the amorphous silicon in the bonding layer 30. By utilizing a fluence that exceeds the ablation threshold of silicon, the bonding layer 30 or at least a portion thereof can be deformed into a powder residue 205, thereby helping to remove the flexible glass substrate 12 from the carrier substrate 20. it can. The rate at which the silicon can be removed and the flexible glass substrate 12 can be removed depends at least in part on the fluence, pulse frequency, and scan speed of the laser. In order to increase the scanning speed, in addition to the pulse frequency, the fluence may be increased. Focusing the laser near the contact surface between the silicon and the flexible glass substrate 12 can help remove the flexible glass substrate 12 more effectively.

  Referring to FIG. 16, in some embodiments, when the amorphous silicon of the bonding layer 30 is melted (as opposed to after the polycrystalline silicon structure is formed, as shown in FIG. 13), the flexible The glass substrate 12 may be separated from the carrier substrate 20. When the amorphous silicon structure is melted, the bonding strength can be locally reduced using the laser 202 and the laser beam 204, whereby the flexible glass substrate 12 can be peeled off at the melting position 206 and separated. As the silicon cools, the polycrystalline layer 208 remains.

Release of Flexible Glass Substrate Any appropriate method can be used to release the flexible glass substrate 20 from the carrier substrate 12. As an example, stress due to delamination may occur due to the overall tension-compression neutral axis shift in forming the final device utilizing this flexible glass substrate 20. For example, when the flexible glass substrate 20 and the carrier substrate 12 are bonded together, the bonding surface may initially be placed near the stress neutral axis. If the bond is near the neutral axis, the mechanical tensile stress can be minimized. With the flexible glass substrate 20 bonded to the carrier substrate 12, i.e. potentially using a cover glass, the stress neutral axis may be shifted after the device has been fully assembled, which is a tensile along the bonding plane. Stresses and bending stresses can be greatly increased, leading to at least some delamination. Delamination can be initiated and / or completed using any number of instruments, such as, for example, a pry plate, laser, knife, scribing wheel, etchant, and / or manually. The flexible glass substrate may be removed.

Referring to FIG. 17, an application pattern of an exemplary bonding layer 30 is illustrated, wherein the flexible glass substrate 20 is divided or diced into a plurality of segments, sometimes referred to as device units. FIG. 17 shows a plan view of the laminate 100 including the flexible glass substrate 20 bonded to the carrier substrate 12 as described above. The bonding layer (represented by area A ₁ ) can be applied over the entire (or less than) total footprint of the flexible glass substrate 20 on the glass support surface 14 of the carrier substrate 12. In the illustrated embodiment, the flexible glass substrate 20 is further divided into device units 102 (further represented by area A ₂ ) having an outer periphery 104 for further processing. By applying the bonding layer A ₁ under the device unit 102, the device unit 102 may contaminate subsequent processes or prematurely separate the flexible glass substrate 20 (or at least part thereof) from the carrier substrate 12. Leakage of process fluid into the area defined by can be minimized or prevented.

  In the drawing, one flexible glass substrate 20 is shown to be bonded to the carrier substrate 12, but a plurality of flexible glass substrates 20 may be bonded to one carrier substrate 12 or a plurality of carrier substrates 12. In such cases, the carrier substrate 12 may be separated from the plurality of flexible glass substrates 20 simultaneously or in any suitable continuous form.

  Any number of device units 102 can be separated from any number of other device units 102 by cutting along outer periphery 104. Ventilation may be provided to reduce any bulges in the flexible glass substrate 20 or other unwanted effects on the flexible glass substrate 20. A laser or other cutting device may be used to cut individual device units 102 from the flexible glass substrate 20. Furthermore, in order to enable reuse of the carrier substrate 12, when this cutting is performed, only the flexible glass substrate 20 may be cut or scored, and may not be performed on the carrier substrate 12. Etching and / or any other cleaning process can be used to remove any residue left by the tie layer 30. Using etching can also help to remove the flexible glass substrate 20 from the carrier substrate 12.

  Referring to FIG. 18, an embodiment of a method for removing a device unit 140 of a flexible glass substrate 20 comprising, for example, an electrical device 145 or other desired structure from a carrier substrate 12 is shown. Any number of device units 140 can be made from the flexible glass substrate 20 bonded to the carrier substrate, depending on the size of the flexible glass substrate 20 and the size of the device unit 140. For example, the flexible glass substrate may be larger than the size of the second generation, for example, the third generation, the fourth generation, the fifth generation, the eighth generation or more (for example, the sheet size is 100 mm × 100 mm to 3 m × 3 m or more) But you can. In order to allow the user to determine the arrangement of the device unit 140 that he wishes to produce from one flexible glass substrate 20 bonded to the carrier substrate 12, for example with respect to the size, number and shape of the device unit 140. The flexible glass substrate 20 can be provided as shown in FIG. More specifically, a substrate laminate 10 having a flexible glass substrate 20 and a carrier substrate 12 is provided. The flexible glass substrate 20 is bonded to the carrier substrate 12 at a bonding area 142 that surrounds the non-bonding area 144.

  The bonding area 142 is disposed on the outer periphery of the flexible glass substrate 20 and completely surrounds the non-bonding area 144. If the process fluid is confined in an arbitrary gap between the flexible glass substrate 20 and the carrier substrate 12, the confined process fluid may contaminate the subsequent process in which the substrate stack 10 is conveyed. This optional gap can be sealed at the outer periphery of the flexible glass substrate 20 using a continuous bonding area 142 so that process fluid is not trapped. However, in other embodiments, discontinuous coupling areas may be used.

A CO ₂ laser beam may be used to cut the outer periphery 146 of the desired portion 140. The CO ₂ laser is capable of full-body cutting (100% of the thickness) of the flexible glass substrate 20. In CO ₂ laser cutting, the laser beam is focused on the surface 24 of the flexible glass substrate 20 to form a small diameter circular beam shape, which is moved along the required trajectory, followed by a coolant nozzle. You may do it. The coolant nozzle may be, for example, an air nozzle that delivers a stream of compressed air through a small diameter orifice onto the surface of the thin sheet. It is also possible to utilize water or air-liquid mist. When the outer periphery 146 of the device unit 140 is cut, the device unit 140 can be detached from the remaining flexible glass substrate 20. An energy input that changes the structure of the coupling layer 30 may then be applied to the coupling layer 30. This structural change reduces the bonding strength of the bonding layer 30 and helps separate the remaining flexible glass substrate 20 from the carrier substrate 12.

  Referring to FIG. 19, an embodiment of a method for releasing the flexible glass substrate 20 from the carrier substrate 12 is shown. When the flexible glass substrate 20 is processed to include the desired device 150 (eg, LCD, OLED, or TFT electronics) and, for example, the device unit 140 is removed, the remaining flexible glass substrate 20 (or the entire flexible glass substrate 20). ) Is released from the carrier substrate 12. In this embodiment, the bonding layer 130 may be formed as a peripheral bond 152 that forms a bonded area 154 and a non-bonded area 156. Laser 158 directs laser beam 160 (eg, having a wavelength between about 400 nm and 750 nm) between flexible glass substrate 20 and carrier substrate 12 to locally heat some portions of coupling layer 30. To do. LED and flashlamp light sources tuned for absorption of the bonding layer 30 are also possible. For example, a laser 158 can be used to locally heat and oxidize the carbon-based bonding layer 30. The peripheral bond 152 is close to the outer periphery of the flexible glass substrate 20 and its cross-sectional area is relatively small (for example, compared to the bond over the entire width of the flexible glass substrate 20), so that the carbon-based bond layer 30 is closer. This allows the peripheral coupling 152 to help local heating of the carbon-based coupling layer 30 by the laser 158.

  The tie layer described above can provide an inorganic adhesion approach that allows the use of thin flexible glass substrates within existing equipment and manufacturing conditions. The carrier substrate can be reused with various flexible glass substrates. A laminate comprising a carrier substrate, a flexible glass substrate and a bonding layer may be assembled and then transported for further processing. Alternatively, some laminates may be assembled prior to transportation, or the laminates may not be assembled prior to transportation. The carrier substrate need not be as good as new for use as a carrier substrate. For example, the carrier substrate may have received excessive cords or streaks that render it unsuitable for use as a display device. When the carrier substrate is used, it is possible to avoid problems when the thin substrate is directly used, such as the formation of a dent around the vacuum hole and the problem of increasing static electricity. The height of the bonding layer may be thin (eg, less than about 10 μm, or between about 1 and 100 μm), thereby minimizing flatness problems such as deflection and over the carrier substrate. Or as a film that is applied continuously, such as locally around the periphery.

  In the foregoing 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. It will be apparent, however, to one of ordinary skill in the art who has benefited from the present disclosure that the present invention may be practiced in other embodiments that depart from the specific details disclosed herein. Moreover, descriptions of well-known devices, methods, and materials may be omitted so as not to obscure the description of various principles of the invention. Finally, wherever applicable, the same reference numbers indicate similar elements.

  In this document, ranges may be expressed from “about” one particular value and / or “about” another particular value. When a range is expressed in this way, 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 should be understood that that particular value forms another embodiment. It should be further understood that the endpoints of each range are important in relation to the other endpoint and independent of the other endpoint.

  As used in this document, for example, top, bottom, right, left, front, back, top, bottom, etc., terms that refer to the direction of the drawing and are absolute It is not intended to be.

  Unless explicitly stated otherwise, any method specified herein is not intended to be construed as requiring that the steps be performed in any particular order. Therefore, if the order in which these steps are performed is not actually stated in a method claim, or specifically stated in the claim or description, these steps should be limited to a particular order. If not, it is not intended in any way that order is inferred. This includes all possible manifestations, including logic issues regarding the placement of steps or operational flows, obvious meanings derived from grammar construction or punctuation, and the number or type of embodiments described herein. It is applied as a principle of interpretation that is not done.

  In this document, the singular includes the plural object unless the context clearly dictates otherwise. Thus, for example, reference to a “component” includes aspects having two or more of this component unless the context clearly indicates otherwise. It should be emphasized that the above-described embodiments of the present invention, particularly any "preferred" embodiments, are merely possible examples and are merely illustrative for a clear understanding of the various principles of the invention. Many variations 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 variations are intended to be included herein within the scope of this disclosure and the following claims.

DESCRIPTION OF SYMBOLS 10 Board | substrate laminated body 12 Carrier board | substrate 14 Glass support surface 20 Flexible glass board | substrate 22 1st wide surface 24 2nd wide surface 30 Binding layer 47 Energy input 200 Laser 202 Laser beam

Claims (13)

A method for processing a flexible glass substrate, comprising:
Providing a substrate laminate comprising a flexible glass substrate bonded to a carrier substrate using an inorganic bonding layer that undergoes a structural change upon receiving energy input; and
Providing the energy input to the inorganic bonding layer to initiate the structural change that reduces the bond strength of the inorganic bonding layer to separate the flexible glass substrate from the carrier substrate;
A method comprising the steps of: A method for processing a flexible glass substrate, comprising:
Providing a carrier substrate having a glass support surface;
Providing the flexible glass substrate having a first wide surface and a second wide surface;
Bonding the first wide surface of the flexible glass substrate to the glass support surface of the carrier substrate using an inorganic bonding layer; and
Reducing the bond strength between the flexible glass substrate and the carrier substrate by changing the structure of the inorganic bonding layer to remove the flexible glass substrate from the carrier substrate;
A method comprising the steps of:   Providing energy input to the inorganic bonding layer to change the structure of the inorganic bonding layer to reduce the bonding strength between the flexible glass substrate and the carrier substrate. The method according to claim 2.   4. A method according to claim 1 or 3, wherein the energy input is thermal energy or light energy that results in heating the inorganic tie layer to at least 250C.   The method according to claim 1, wherein the inorganic bonding layer is locally heated using a laser or a flash lamp.   The method according to claim 1, wherein the inorganic bonding layer includes an inorganic bonding material positioned along the outer periphery of the flexible glass substrate.   The method according to claim 1, wherein the structural change includes crystallization, an increase in porosity of the inorganic bonding layer, or an increase in microfracture of the inorganic bonding layer.   The method according to claim 1, further comprising the step of removing the flexible glass substrate from the carrier substrate after providing the energy input to the inorganic bonding layer.   The method of any one of claims 1 to 8, wherein the bonding material comprises one or more of glass, glass ceramic, ceramic, carbon, and silicon.   10. The method of claim 1 or 3-9, wherein the energy input is thermal energy or light energy and the step of heating the bonding material to a temperature of at least 250 ° C. without reducing the bonding strength. The method according to any one of the above. A substrate laminate,
A carrier substrate having a glass support surface;
A flexible glass substrate supported by the glass support surface of the carrier substrate; and
An inorganic bonding layer for bonding the flexible glass substrate to the carrier substrate, and for removing the flexible glass substrate from the carrier substrate, the structure is changed to increase the bonding strength between the flexible glass substrate and the carrier substrate. An inorganic tie layer comprising a bonding material to be reduced,
The board | substrate laminated body characterized by the above-mentioned.   The substrate laminate according to claim 11, wherein the bonding material includes at least one of glass, glass ceramic, and ceramic.   The substrate laminate according to claim 11 or 12, wherein the structural change includes crystallization, an increase in porosity of the inorganic bonding layer, or an increase in microfracture of the inorganic bonding layer.

Images