High temperature stable curable bonding composition

Abstract

The curable bonding composition includes a free radically polymerizable bismaleimide resin, a polymerizable siloxane-based release agent, and an optional thermal or UV free radical initiator. The curable composition is a coatable composition. Upon curing, the cured composition is high temperature stable, exhibiting a weight loss of 2.5% or less in 1 hour at a temperature of at least 300° C. as measured by isothermal TGA (thermogravimetric analysis), and remains releasable by peeling after exposure to at least 300° C. for 1 hour.

Description

Summary of the Invention

[0001] Disclosed herein are high temperature stable curable bonding compositions, laminate bodies prepared with the curable bonding compositions, and methods for preparing the laminates.

[0002] In some embodiments, the curable bonding composition comprises at least one free radical polymerizable bismaleimide resin, at least one polymerizable siloxane-based release agent, and an optional thermal or UV free radical initiator. The curable composition is a coatable composition that is 100% solids or solvent diluted. Upon curing, the cured composition is high temperature stable, exhibiting a weight loss of 2.5% or less at a temperature of at least 300° C. and 1 hour as measured by isothermal TGA (thermogravimetric analysis), and remains releasable by peeling after exposure to at least 300° C. and 1 hour.

[0003] A laminate is also disclosed herein. In some embodiments, the laminate includes a substrate to be processed, a bonding layer in contact with the substrate, a light-to-heat conversion layer including a light absorber and a thermally decomposable material disposed under the bonding layer, and a light-transmitting support disposed under the light-to-heat conversion layer. The bonding layer is the above-mentioned cured bonding composition.

[0004] A method for preparing a laminate is also disclosed. In some embodiments, the method includes: coating a photothermal conversion layer precursor containing a light absorber and a thermally decomposable material or a monomer or oligomer as a precursor of the thermally decomposable material on a light-transmitting support; drying the photothermal conversion layer precursor until it solidifies or hardens to form a photothermal conversion layer on the light-transmitting support; applying a curable bonding composition to a substrate to be processed or the photothermal conversion layer to form a bonding layer; and bonding the substrate to be processed and the photothermal conversion layer under reduced pressure through the bonding layer to form a laminate. The bonding layer is the above-mentioned cured bonding composition. [Brief description of the drawings]

[0005] The present application may be more fully understood from consideration of the following detailed description of various embodiments of the disclosure in conjunction with the accompanying drawings.

[0006] [Figure 1A] FIG. 1 is a cross-sectional view of an embodiment of a laminate of the present disclosure. [Figure 1B] FIG. 2 is a cross-sectional view of another laminate embodiment of the present disclosure.

[0007] In the following description of the exemplary embodiments, reference is made to the accompanying drawings, which illustrate, by way of example, various embodiments in which the present disclosure may be practiced. It should be understood that the embodiments may be utilized and structural changes may be made without departing from the scope of the present disclosure. The drawings are not necessarily drawn to scale. Like numbers used in the drawings indicate like components. However, it will be understood that the use of numbers to indicate components in a given figure is not intended to limit the components in another figure that are indicated with the same number. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The use of adhesives and bonding compositions is increasing in a wide range of applications. The most common use of adhesives is bonding, i.e., adhering one substrate to another. In many cases, adhesives are designed to bond permanently or at least for a long time, and the adhesive is incorporated into the final article. Examples range from optical adhesives that bond layers of films used on display screens to structural adhesives that secure bumpers to automobiles.

[0009] On the other hand, there are also special types of adhesive articles that are not designed to adhere articles permanently or for long periods of time, and are instead described as "processing" articles. This means that the adhesive holds components temporarily or provides a temporary protective layer to components so that a process or series of processes can be carried out. After the processing step, the adhesive article is removed. Typically, removal of the adhesive article should leave no residue or leave an easily removable residue. A simple example of an adhesive processing article is masking tape. If one wants to paint a wall without the paint sticking to the baseboard, one applies masking tape to the baseboard at the wall / baseboard interface. The wall is then painted. The masking tape functions to prevent paint from adhering to the baseboard. The masking tape is removed without leaving any residue.

[0010] Current industrial needs, especially in the electronic and optical industry, as well as in the manufacture of consumer goods and other articles, are much more complex and specialized in their requirements compared to the simple examples above. An illustrative example is the processing of semiconductor wafers. Wafers are typically small articles on which various processing steps are performed. Often, processing adhesives are used to hold the wafers while these processes are performed. Many of these processes involve intense physical processes, such as polishing and grinding, as well as exposure to high temperatures. Thus, processing adhesives are needed that hold the wafers securely in place during these processes. Once the processing steps are complete, the wafers need to be removable from the processing articles. Such processing adhesives have various and apparently contradictory requirements, such as holding strongly but being easily removed.

[0011] Disclosed herein is a curable bonding composition comprising at least one free radically polymerizable bismaleimide resin, at least one polymerizable siloxane-based release agent, and an optional thermal or UV free radical initiator. The curable composition is a coatable composition, either 100% solids or solvent diluted, that upon curing is high temperature stable, exhibiting a weight loss of 2.5% or less at temperatures of at least 300°C and 1 hour as measured by isothermal TGA (thermogravimetric analysis), and remains releasable by peeling after exposure to at least 300°C and 1 hour.

[0012] Also disclosed is a laminate comprising a substrate to be processed, an adhesive layer in contact with the substrate, the adhesive layer comprising the cured curable bonding composition described above, a light-to-heat conversion layer comprising a light absorber and a thermally decomposable material disposed under the adhesive layer, and a light-transmitting support disposed under the light-to-heat conversion layer. Also disclosed is a method for preparing such a laminate.

[0013] The terms "adhesive" and "bonding composition" are used interchangeably and refer to polymeric compositions useful for bonding.

[0014] The term "curing" as used herein refers to polymerization. The term curing is used broadly in the art and may refer to crosslinking or vulcanization. In this disclosure, curing simply means polymerization and is not synonymous with crosslinking, although it may include crosslinking.

[0015] As used herein, the terms "siloxane" and "siloxane-based" refer to polymers or polymeric units containing siloxane units. The terms silicone or siloxane are used interchangeably and refer to units having dialkyl or diaryl siloxane (-SiRO-) repeating units.

[0016] As used herein, the term "adjacent" when referring to two layers means that the two layers are in close proximity to one another with no intervening open space between them. They may be in direct contact with one another (e.g., laminated together) or there may be an intervening layer.

[0017] The terms "polymer" and "macromolecule" are used herein to be consistent with common usage in chemistry. Polymers and macromolecules are composed of many repeating subunits. As used herein, the term "macromolecule" is used to describe a group attached to a monomer having multiple repeating units. The term "polymer" is used to describe the resulting material formed from a polymerization reaction.

[0018] The term "100% solids composition" refers to a composition that is essentially free of solvent or that is solvent-free.

[0019] The term "solvent-diluted" refers to a composition to which a solvent has been added to reduce the viscosity and increase the coatability of the composition.

[0020] The term "alkyl" refers to a monovalent group that is a group of an alkane that is a saturated hydrocarbon. An alkyl can be linear, branched, cyclic, or a combination thereof, and typically has 1 to 20 carbon atoms. In some embodiments, an alkyl group contains 1 to 18, 1 to 12, 1 to 10, 1 to 8, 1 to 6, or 1 to 4 carbon atoms. Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl, and ethylhexyl.

[0021] The term "aryl" refers to a monovalent group that is aromatic and carbocyclic. An aryl can have from 1 to 5 rings that are connected or fused to the aromatic ring. Other ring structures can be aromatic, non-aromatic, or combinations thereof. Examples of aryl groups include, but are not limited to, phenyl, biphenyl, terphenyl, anthryl, naphthyl, acenaphthyl, anthraquinonyl, phenanthryl, anthracenyl, pyrenyl, perylenyl, and fluorenyl.

[0022] The term "alkylene" refers to a divalent group that is a radical of an alkane. Alkylene may be straight chain, branched chain, cyclic, or a combination thereof. Alkylene often has 1 to 20 carbon atoms. In some embodiments, alkylene contains 1 to 18, 1 to 12, 1 to 10, 1 to 8, 1 to 6, or 1 to 4 carbon atoms. The radical centers of the alkylene can be on the same carbon atom (i.e., an alkylidene) or on different carbon atoms.

[0023] The terms "free radically polymerizable" and "ethylenically unsaturated" are used interchangeably and refer to a reactive group that contains a carbon-carbon double bond that can be polymerized via a free radical polymerization mechanism.

[0024] Disclosed herein is a curable bonding composition comprising at least one free radically polymerizable bismaleimide resin, at least one polymerizable siloxane-based release agent, and an optional thermal or UV free radical initiator. The curable composition is a coatable 100% solids composition, and upon curing, the cured composition is high temperature stable, exhibiting a weight loss of 2.5% or less at temperatures of at least 300° C. and 1 hour as measured by isothermal TGA (thermogravimetric analysis), and remains releasable by peeling after exposure to at least 300° C. and 1 hour.

[0025] The curable composition comprises at least one free radically polymerizable bismaleimide resin. A wide range of free radically polymerizable bismaleimide resins are suitable. In some embodiments, the free radically polymerizable bismaleimide resin comprises at least one compound of Structure 1: [ka] wherein R comprises a divalent linking group containing an alkylene group, an aromatic group, a heteroatom-containing group, a siloxane group, one or more polyimide linkages, or a combination thereof. Includes.

[0026] A wide range of free radically polymerizable bismaleimide resins are commercially available. Examples include BMI-689, BMI-1500, BMI-1700, BMI-3000, and BMI-5000 from Designer Molecules. Exemplary structures are shown below as (a)-(d). [ka]

[0027] In some embodiments, the free radically polymerizable bismaleimide resin comprises at least one compound of Structure 1, where R comprises an oligomeric group containing a polyimide group.

[0028] In some embodiments, the free radically polymerizable bismaleimide resin comprises at least one compound of Structure 1, where R comprises a siloxane-based group. One advantage of this type of bismaleimide resin is that the presence of the siloxane group can aid in the release properties of the cured bonding composition. Examples of such resins include Compound 1, as shown below, as described in U.S. Pat. No. 4,923,997: [ka]

[0029] In compound 1, R' is an alkenylene or alkylene group, R'' is independently a hydrocarbon or halohydrocarbon group, and n is an integer.

[0030] In many embodiments, the at least one free radically polymerizable bismaleimide resin comprises a mixture of bismaleimides. The use of a combination of resins provides flexibility in controlling the viscosity of the coatable 100% solids bonding composition as well as the ability to control the final properties of the cured coatable composition.

[0031] The curable bonding composition also includes at least one polymerizable siloxane-based release agent, meaning that the siloxane-based release agent is copolymerizable with the bismaleimide resin or a combination of the above resins. In some embodiments, the at least one siloxane-based release agent includes a siloxane (meth)acrylate, a siloxane hydride, or a siloxane maleimide.

[0032] A wide variety of siloxane (meth)acrylates are commercially available from Evonik Industries under the trade names TEGO Rad 2300, TEGO Rad 2250, TEGO Rad 2100, and TEGO Rad 2500. These compounds are similar and have the general structure of Compound 2, shown below: [ka] For TEGO Rad 2300, m is 1 to 5 and n is such that the ratio of acrylate groups to methyl groups is 1:20 to 1:50. For TEGO Rad 2100 and TEGO Rad 2500, n ranges from 10 to 20 and m is 0.5 to 5. Another commercially available siloxane (meth)acrylate is EBECRYL 350, a silicone diacrylate from Allnex.

[0033] An example of a siloxane hydride is HMS-301 methylhydrosiloxane-dimethylsiloxane copolymer, trimethylsiloxy terminated, silicone hydride from Gelest.

[0034] Examples of siloxane maleimides include, for example, compound 1 shown above.

[0035] Free radical curing of the curable composition can be achieved by exposure to electron beam (E-beam) or gamma radiation. The use of E-beam or gamma radiation does not require the use of an initiator. Various procedures for E-beam curing and gamma curing are known. Curing depends on the specific equipment used, and those skilled in the art can define dose calibration models for specific equipment, geometries, and line speeds, as well as other well-understood process parameters.

[0036] Commercially available electron beam generators are readily available. In the examples described herein, the irradiation process was carried out with a Model CB-300 electron beam generator (available from Energy Sciences, Inc., Wilmington, Mass.). Commercially available gamma irradiation equipment includes equipment often used for gamma radiation sterilization of products for medical applications.

[0037] In some embodiments, the curable composition may further comprise at least one initiator. The at least one initiator is a free radical initiator. The initiator may be a thermal initiator or a photoinitiator. In many embodiments, the initiator is a thermal initiator. A thermal initiator is a species that generates free radicals when heated. Many possible thermal free radical initiators are known in the art of vinyl monomer polymerization and can be used. Exemplary thermal free radical polymerization initiators useful herein are organic peroxides, organic hydroperoxides, and azo-based initiators that generate free radicals. Useful organic peroxides include, but are not limited to, compounds such as benzoyl peroxide, di-t-amyl peroxide, t-butyl peroxybenzoate, and di-cumyl peroxide. Useful organic hydroperoxides include, but are not limited to, compounds such as t-amyl hydroperoxide and t-butyl hydroperoxide. Useful azo group initiators include, but are not limited to, VAZO compounds available from DuPont, such as VAZO 52 (2,2'-azobis(2,4-dimethylpentanenitrile)), VAZO 64 (2,2'-azobis(2-methylpropanenitrile)), VAZO 67 (2,2'-azobis(2-methylbutanenitrile)), and VAZO 88 (2,2'-azobis(cyclohexanecarbonitrile)). Additional commercially available thermal initiators include, for example, LUPERSOL 130 (2,5-dimethyl-2,5-di-(t-butylperoxy)hexyne-3) available from Sigma-Aldrich (St. Louis, MO), and LUPEROX 101 (2,5-dimethyl-2,5-di-(tert-butylperoxoxy)hexane) and LUPEROX 231 (1,1-bis(tertbutylperoxide)-3,3,5-trimethylcyclohexane) available from Arkema, Inc. (King of Prussia, PA), and UN3114 (BCHPC) (di(4-(tertbutylcyclohexyl)peroxydicarbonate) available from United Initiators.

[0038] In some embodiments, the initiator may comprise a photoinitiator, meaning that the initiator is activated by light, typically ultraviolet (UV) light. Examples of suitable free radical photoinitiators include DAROCURE 4265, IRGACURE 651, IRGACURE 1173, IRGACURE 819, LUCIRIN TPO, LUCIRIN TPO-L, available from BASF (Charlotte, NC), and OMNIRAD 819 (bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide), available from IGM Resins.

[0039] A sufficient amount of initiator is typically used to carry out the polymerization to the desired temperature and conversion. The total amount of photoinitiator used is typically in the range of about 0.01% to about 5.0% by weight, or in the range of about 0.1% to about 2.0% by weight, based on the total monomer content. The total amount of thermal initiator used is typically in the range of about 0.1% to about 5.0% by weight, or in the range of about 0.5% to about 4.0% by weight, based on the total monomer content.

[0040] Many embodiments of the curable bonding composition are 100% solids. If desired, especially if the viscosity makes coating difficult or too slow, the curable composition may be solvent diluted, i.e., the curable bonding composition further comprises a solvent. A wide variety of solvents are suitable, with ethers and acetates being particularly suitable. Examples of suitable solvents include PGMEA (propyl glycol monomethyl ether acetate) and PGME (propyl glycol monomethyl ether).

[0041] Typically, prior to curing, the solvent is removed from the coated composition by drying. Drying can be accelerated by exposure to elevated temperatures. If a solvent is used and dried prior to curing, the temperature of drying is below the activation temperature of the optional thermal initiator, if one is used.

[0042] As discussed above, the bonding composition has a variety of properties that make it suitable for use in a wide range of processes. Among the desirable properties is that the cured composition is high temperature stable, losing no more than 2.5% weight in one hour at a temperature of at least 300° C. as measured by isothermal TGA (thermogravimetric analysis). This is desirable since many processes involve exposing the cured adhesive to a temperature of at least 300° C. for one hour. High temperature stability is further characterized by the cured adhesive remaining releasable by peeling after exposure to at least 300° C. for one hour.

[0043] While 300°C is a very extreme condition for the bonding composition to withstand, in some embodiments, the conditions are even more extreme. For example, in some embodiments, the cured composition is high temperature stable, losing no more than 4.5% weight at a temperature of at least 350°C for 1 hour, as measured by isothermal TGA (thermogravimetric analysis). This stability is further characterized by the fact that the cured adhesive composition remains removable by peeling or by chemical solvent cleaning after exposure to at least 350°C for 1 hour. In this more extreme set of conditions, some residue of the cured adhesive composition may remain behind, necessitating the use of chemical solvent cleaning in addition to removal by peeling.

[0044] Also disclosed is a laminate comprising a substrate to be processed, an adhesive layer in contact with the substrate, the adhesive layer comprising the above-mentioned cured curable bonding composition, a light-to-heat conversion layer comprising a light absorber and a thermally decomposable material disposed under the adhesive layer, and a light-transmitting support disposed under the light-to-heat conversion layer.Methods for preparing such laminates and the use of such laminates for processing, for example, wafers are discussed in U.S. Patent No. 7,534,498.

[0045] The bonding composition of the present invention is suitable for use in the apparatus discussed in U.S. Patent No. 7,534,498, using the method disclosed therein. The bonding composition is described in detail above and includes at least one free radical polymerizable bismaleimide resin, at least one polymerizable siloxane-based release agent, and an optional thermal or ultraviolet free radical initiator. As mentioned above, the bonding composition of the present invention is particularly suitable for use because the curable composition is a coatable 100% solids composition, and when cured, the cured composition is high temperature stable, losing no more than 2.5% weight at a temperature of at least 300° C. for 1 hour, as measured by isothermal TGA (thermogravimetric analysis), and remains releasable by peeling after exposure to at least 300° C. for 1 hour.

[0046] A wide variety of substrates to be processed are suitable. In many embodiments, the substrate is a brittle material. Examples of brittle materials include semiconductor wafers such as silicon and gallium arsenide, as well as quartz wafers, sapphire and glass.

[0047] The laminate also includes a photothermal conversion layer disposed under the above-mentioned bonding layer. The photothermal conversion layer includes a light absorber and a thermally decomposable material. Radiant energy applied to the photothermal conversion layer in the form of laser light or the like is absorbed by the light absorber and converted into thermal energy. The generated thermal energy rapidly increases the temperature of the photothermal conversion layer, which reaches the thermal decomposition temperature of the thermally decomposable material in the photothermal conversion layer, causing thermal decomposition of the material. It is believed that the gas generated by thermal decomposition forms a void layer (e.g., air space) in the photothermal conversion layer, dividing the photothermal conversion layer into two parts, thereby separating the support and the substrate.

[0048] A wide range of materials are suitable for use in the light-to-heat conversion layer. In some embodiments, the light absorber comprises carbon black, graphite powder, fine-grained metal powder such as iron, aluminum, copper, nickel, cobalt, manganese, chromium, zinc and tellurium, metal oxide powder such as black titanium dioxide, or dye or pigment. In some embodiments, the light absorber is carbon black, and the total amount of carbon black and transparent filler in the light-to-heat conversion layer is 5-70% by volume based on the volume of the light-to-heat conversion layer.

[0049] A wide variety of thermally decomposable materials are suitable, including the thermally decomposable resins described in US Pat. No. 7,534,498.

[0050] In some embodiments, the photothermal conversion layer further comprises a transparent filler. The transparent filler functions to prevent the photothermal conversion layer from re-adhering when the photothermal conversion layer is separated due to the formation of a void layer as a result of the thermal decomposition of the thermally decomposable material. Examples of suitable transparent fillers include silica, talc and barium sulfate. In some embodiments, the light absorber is carbon black, and the total amount of carbon black and transparent filler in the photothermal conversion layer is 80% or more of the filler volume concentration.

[0051] The laminate also includes a light-transmitting support. A wide range of light-transmitting supports are suitable. The light-transmitting support is a material that transmits light, such as laser light, while providing a surface that keeps the substrate to be processed flat and does not damage the substrate during processing. A particularly suitable light-transmitting support is glass.

[0052] The laminate may also include additional optional layers. In some embodiments, the laminate further includes a first intermediate layer between the bonding layer and the light-to-heat conversion layer. Examples of suitable first intermediate layers include multilayer optical films. The laminate may also include a second intermediate layer, the second intermediate layer being placed between the light-to-heat conversion layer and the light-transmitting support, and the second intermediate layer and the light-transmitting support being bonded via a second bonding layer (typically an adhesive layer such as a pressure-sensitive adhesive). Typically, the second intermediate layer is a coatable curable material that is applied to the light-to-heat conversion layer and cured.

[0053] Also disclosed is a method for manufacturing a laminate.In some embodiments, the method includes: coating a photothermal conversion layer precursor containing a light absorber and a thermally decomposable material or a monomer or oligomer as a precursor of the thermally decomposable material on a light-transmitting support; drying the photothermal conversion layer precursor until it solidifies or hardens to form a photothermal conversion layer on the light-transmitting support; applying a curable bonding composition to a substrate to be processed or the photothermal conversion layer to form a bonding layer, the curable bonding composition being described in detail above; and bonding the substrate to be processed and the photothermal conversion layer under reduced pressure through the bonding layer to form a laminate.

[0054] As noted above, in some embodiments, the curable composition is a coatable, 100% solids composition, and upon curing, the cured composition is high temperature stable, exhibiting a weight loss of 2.5% or less in 1 hour at a temperature of at least 300° C. as measured by isothermal TGA (thermogravimetric analysis), and remains removable by peeling after exposure to at least 300° C. for 1 hour. In other embodiments, the curable composition, upon curing, the cured bonding composition remains removable by peeling or by chemical solvent washing after exposure to at least 350° C. for 1 hour.

[0055] Processing steps utilizing laminates of the present disclosure are described, for example, in US Pat. No. 7,534,498.

[0056] The present disclosure may be more fully understood by reference to the drawings, which are cross-sectional views of embodiments of laminates of the present disclosure. Figure 1A shows a laminate 1 including a processed substrate 2, a cured bonding layer 3, a photochemical conversion layer 4, and a light-transmitting support 5, stacked in that order. Each of these layers has been discussed in detail above.

[0057] 1B shows an alternative embodiment of a laminate 1 including, stacked in that order, a processed substrate 2, a cured bonding layer 3, a first interlayer 6, a photochemical conversion layer 4, a second interlayer 9, a second bonding layer 3, and a light-transmitting support 5. Each of these layers has been discussed in detail above. EXAMPLES

[0058] These examples are for illustrative purposes only and are not intended to limit the scope of the appended claims. All parts, percentages, ratios, etc. in the examples and elsewhere herein are by weight unless otherwise indicated. The following abbreviations are used: cm = centimeters, RPM = revolutions per minute, kg = kilograms, cPs = centipoise, min = minute, hr = hour, mJ = millijoules. [Table 1]

[0059] Test Method Thermogravimetric analysis (TGA) TGA analysis of adhesive samples was performed under N2 gas protection to measure weight loss at 300 or 350°C and 1 hour. Weight loss of adhesive samples at 300°C or 350°C and 1 hour was measured using a TGA (954000.901) from TA instrument. The temperature ramp rate was 10°C / min.

[0060] 90 degree peel strength test The 90 degree peel force of the adhesive was measured using an Imass SP-2100 (Imass, Inc.) The test conditions were: load cell capacity: 5 kg, speed: 12 in / min (30 cm / min), delay: 2 seconds, test time: 2 or 5 seconds, sample width: 0.5 in (13 cm), and the peel force was expressed in Newtons.

[0061] Examples / Comparative Examples Examples 1 to 6 and Comparative Examples CE1 and CE2: Sample preparation Preparation of UV-curable formulation: An adhesive formulation was prepared using the ingredients listed in Table 1 below. The ingredients were added to a light-proof plastic mixing container. The mixture in the container was heated in a 90° C. oven for 20 minutes. The mixture was mixed by hand and again using a vacuum high speed mixer: DAC 800.2 VAC-P (FlackTek Inc, Landrum, SC) at 2000 rpm and 10 torr vacuum for 3 minutes.

[0062] Preparation of thermosetting formulations: An adhesive formulation was prepared using the ingredients listed in Table 1 below (except for the thermal initiator). The ingredients were added to a plastic mixing container. The mixture in the container was heated in an oven at 90° C. for 20 minutes. The mixture was mixed by hand and mixed again using a vacuum high speed mixer: DAC 800.2 VAC-P (FlackTek Inc, Landrum, SC) at 2000 rpm and 10 torr vacuum for 3 minutes. After mixing and allowing the mixture to cool, the thermal initiator was added and first mixed by hand, then the high speed mixing process was repeated again at 1500 rpm.

[0063] Spin Coating: The adhesive was spin coated onto a 100 mm diameter silicon wafer under the following conditions: first, 1200 rpm for 20 seconds; second, 2000 rpm for 40 seconds.

[0064] UV or Heat Curing: The above spin-coated adhesive and wafer are then thermally (150-220 °C for 1-1.5 h) or UV (2400 mJ / cm 2 ) and cured.

[0065] Baking process: The above cured adhesive and wafer were placed on a hot plate (Model 10, Brewer science, Inc.) protected with N2 gas, and the temperature was increased to 300°C at a rate of 6°C / min. After baking at 300°C for 1 hour, the hot plate was cooled to room temperature.

[0066] test The formulations were tested for TGA weight loss and 90 degree peel adhesion (initial and after the bake process) and the results are shown in Table 2 below. [Table 2] [Table 3]

Claims

1. 1. A curable bonding composition comprising: at least one free-radically polymerizable bismaleimide resin; at least one polymerizable siloxane-based release agent; an optional thermal or ultraviolet free radical initiator; Including, The curable composition is a coatable composition that is 100% solids or solvent diluted, and upon curing, the cured composition is high temperature stable, losing no more than 2.5% weight at a temperature of at least 300°C for 1 hour as measured by isothermal TGA (thermogravimetric analysis), and remains releasable by peeling after exposure to at least 300°C for 1 hour.

2. The curable bonding composition of claim 1 , wherein the at least one free-radically polymerizable bismaleimide resin comprises a mixture of bismaleimides.

3. The free radically polymerizable bismaleimide resin comprises at least one compound of Structure 1: 【Chemistry 1】 wherein R comprises a divalent linking group containing an alkylene group, an aromatic group, a heteroatom-containing group, a siloxane group, one or more polyimide linkages, or a combination thereof. The curable bonding composition of claim 1 comprising:

4. The curable bonding composition of claim 3 wherein R comprises an oligomeric group containing a polyimide group.

5. 10. The curable bonding composition of claim 1, wherein upon curing, the cured composition is high temperature stable, losing no more than 4.5% weight at a temperature of at least 350°C for 1 hour as measured by isothermal TGA (thermogravimetric analysis), and remains releasable by peeling or by chemical solvent washing after exposure to at least 350°C for 1 hour.

6. Processed base material; a bonding layer in contact with the substrate, the bonding layer comprising a cured curable bonding composition; The cured curable bonding composition comprises: at least one free-radically polymerizable bismaleimide resin; at least one polymerizable siloxane-based release agent; an optional thermal or ultraviolet free radical initiator; a bonding layer comprising: the curable composition being a 100% solids or solvent diluted coatable composition, which upon curing is high temperature stable, losing no more than 2.5% weight at a temperature of at least 300°C for 1 hour as measured by isothermal TGA (thermogravimetric analysis), and remains releasable by peeling after exposure to at least 300°C for 1 hour; a light-to-heat conversion layer disposed under the bonding layer and including a light absorber and a thermally decomposable material; a light-transmitting support disposed below the light-to-heat conversion layer; A laminate comprising:

7. The laminate according to claim 6 , wherein the substrate is a silicon wafer.

8. The laminate according to claim 6 , wherein the light-to-heat conversion layer further comprises a transparent filler.

9. 9. The laminate according to claim 8, wherein the light absorber is carbon black, and the total amount of the carbon black and the transparent filler in the light-to-heat conversion layer is 5 to 70% by volume based on the volume of the light-to-heat conversion layer.

10. 9. The laminate according to claim 8, wherein the light absorber is carbon black, and the total amount of the carbon black and the transparent filler in the light-to-heat conversion layer is 80% or more of the volume concentration of the filler.

11. The laminate according to claim 6 , further comprising a first intermediate layer between the bonding layer and the photothermal conversion layer.

12. The laminate according to claim 11, wherein a second intermediate layer is provided between the photothermal conversion layer and the light-transmitting support, and the second intermediate layer and the light-transmitting support are bonded via another bonding layer.

13. 1. A method for manufacturing a laminate, comprising: Coating a light-to-heat conversion layer precursor containing a light absorber and a thermally decomposable material or a monomer or oligomer as a precursor of the thermally decomposable material on a light-transmitting support; drying the photothermal conversion layer precursor until it solidifies or hardens to form a photothermal conversion layer on the light-transmitting support; A curable bonding composition is applied to a substrate to be processed or the light-to-heat conversion layer to form a bonding layer, wherein the curable bonding composition is at least one free-radically polymerizable bismaleimide resin; at least one polymerizable siloxane-based release agent; an optional thermal or ultraviolet free radical initiator; the curable composition is a 100% solids or solvent diluted coatable composition that upon curing forms a bonding layer that is high temperature stable, losing no more than 2.5% weight at a temperature of at least 300°C for 1 hour as measured by isothermal TGA (thermogravimetric analysis), and remains releasable by peeling after exposure to at least 300°C for 1 hour; and bonding the workpiece substrate and the photothermal conversion layer together under reduced pressure via the bonding layer to form a laminate.

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