Temporary adhesive material for substrate processing and method for manufacturing a laminate

Abstract

To provide a temporary adhesion material for processing a substrate which facilitates temporary adhesion and detachment of the substrate and a support body, is rapid in a temporary adhesion material layer forming process, is excellent in dimension stability and heat process resistance, and can improve productivity of a thin substrate, and a method of producing a laminate using the same.SOLUTION: A temporary adhesion material for processing a substrate for temporarily adhering a substrate having a back face to be processed to a support body, contains 10 pts.mass or more and 100 pts.mass or less based on 100 pts.mass of the total mass of a siloxane bond-containing polymer having a weight average molecular weight measured by GPC of 3,000 or more and 700,000 or less. The temporary adhesion material has a first temporary adhesion material layer, and a second temporary adhesion material layer different from the first adhesion material layer, where at least one layer of the first temporary adhesion material layer and the second temporary adhesion material layer has a minimum value of a shear viscosity in a range of 130°C or higher and 250°C or lower of 1 Pa s or more and 10,000 Pa s or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a temporary bonding material for substrate processing and a method for manufacturing a laminate using the temporary bonding material for substrate processing.

Background Art

[0002] Three-dimensional semiconductor packaging has become essential for achieving higher density and larger capacity. The three-dimensional packaging technology is a semiconductor manufacturing technology in which a single semiconductor chip is thinned and then stacked in multiple layers while being connected by through-silicon vias (TSVs). To achieve this, it is necessary to thin the substrate on which the semiconductor circuit is formed by grinding the non-circuit forming surface (also referred to as the "back surface"), and further perform an electrode forming process including TSVs on the back surface.

[0003] Conventionally, in the back grinding process of a silicon substrate, a protective tape is attached to the opposite side of the grinding surface to prevent substrate breakage during grinding. However, this tape uses an organic resin film as a support substrate, which has flexibility but insufficient strength and heat resistance, and is not suitable for performing the TSV forming process or the wiring layer forming process on the back surface.

[0004] Therefore, a system has been proposed in which a semiconductor substrate is bonded to a support such as silicon or glass via an adhesive layer, which can sufficiently withstand the processes of back grinding, TSV, and back electrode formation. At this time, the adhesive layer when bonding the substrate to the support is important. This requires that the substrate can be bonded to the support without gaps and has sufficient durability to withstand subsequent processes, and further that the thin substrate can be easily peeled from the support finally. Thus, since it is peeled finally, in this specification, this adhesive layer will be referred to as a temporary bonding layer (or a temporary bonding material layer).

[0005] As known heretofore, as a temporary adhesive layer and its peeling method, there have been proposed a technique (Patent Document 1) of irradiating an adhesive containing a light-absorbing substance with high-intensity light to decompose the adhesive layer and peeling the adhesive layer from the support, and a technique (Patent Document 2) of using a heat-fusible hydrocarbon-based compound as the adhesive and performing bonding and peeling in a heat-melted state. The former technique has problems such as the need for an expensive device such as a laser and a long processing time per substrate. Also, the latter technique is simple because it is controlled only by heating, but the heat stability at a high temperature exceeding 200°C is insufficient, so the applicable range was narrow. Furthermore, in these temporary adhesive layers, although they are not suitable for forming a uniform film thickness on a high-step substrate and for completely adhering to the support, in many cases, the substrate and the support in the subsequent process cannot be peeled, and the substrate is damaged.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] The present invention has been made in view of the above problems, and aims to provide a temporary adhesive material for substrate processing that enables easy temporary adhesion between a substrate and a support, has a fast process for forming a temporary adhesive layer on the substrate or the support, further has excellent dimensional stability, excellent heat process resistance such as CVD (chemical vapor deposition), is easy to peel, and can improve the productivity of the laminate, and a method for manufacturing a laminate using the temporary adhesive material for substrate processing.

Means for Solving the Problems

[0008] In order to solve the above problems, the present invention is a temporary adhesive material for substrate processing for temporarily adhering a substrate to be processed on the back surface to a support, The temporary adhesive material contains 10 to 100 parts by mass of a siloxane bond-containing polymer having a weight average molecular weight of 3,000 or more and 700,000 or less as measured by GPC with respect to 100 parts by mass of the total mass. The temporary adhesive material has a first temporary adhesive layer and a second temporary adhesive layer different from the first temporary adhesive layer. Provided is a temporary adhesive material for substrate processing, wherein at least one of the first temporary adhesive layer and the second temporary adhesive layer has a minimum value of shear viscosity in the range of 130°C or more and 250°C or less and is 1 Pa·s or more and 10,000 Pa·s or less.

[0009] With such a temporary adhesive material for substrate processing of the present invention, the temporary adhesion between the substrate and the support is easy, the dimensional stability is excellent, the formation speed of the temporary adhesive layer is high, the process compatibility with respect to the TSV formation and the substrate backside wiring process is high, and furthermore, the heat process resistance such as CVD is also good, the peeling is easy, and the productivity of the thin substrate can be increased.

[0010] In this case, the first temporary adhesive layer can be composed of a thermoplastic resin.

[0011] With such a temporary adhesive material for substrate processing, the processed substrate can be easily cleaned, so that the productivity of the thin substrate can be further increased.

[0012] Also in this case, the siloxane bond-containing polymer can have a repeating unit represented by the following general formula (1).

Chemical formula

Chemical formula

[0013] In addition, the siloxane bond-containing polymer may have a repeating unit represented by the following general formula (3). [Chemical formula] [In the formula, R 7 ~R 10 represent monovalent hydrocarbon groups having 1 to 8 carbon atoms which may be the same or different. Also, n is an integer from 1 to 100, D is a positive number, and C is 0 or a positive number. However, C + D = 1. Further, Y is a divalent organic group represented by the following general formula (4). [Chemical formula] (In the formula, V is [Chemical formula] is a divalent organic group selected from any of the following, and p is 0 or 1. Also, R 11 , R 12 are each an alkyl group or an alkoxy group having 1 to 4 carbon atoms, and may be the same or different from each other. h is any of 0, 1, and 2. )]

[0014] In addition, the siloxane bond-containing polymer is (p1) an organopolysiloxane having an alkenyl group in the molecule, (p2) an organohydrogenpolysiloxane containing hydrogen atoms (Si-H groups) bonded to two or more silicon atoms in one molecule: an amount such that the molar ratio of the Si-H groups in the (p2) component to the alkenyl groups in the (p1) component is from 0.3 to 15, and (p3) a platinum-based catalyst, may also contain.

[0015] Such a temporary adhesive material for substrate processing according to the present invention is preferable because it has even better heat resistance.

[0016] Further, the present invention also provides a method for manufacturing a laminate in which a substrate and a support are joined via a temporary adhesive material, the method for manufacturing a laminate being characterized by including the following steps (a) to (d). (a) A step of forming a temporary adhesive layer on one or both of the surfaces of the substrate and the support to be joined using the above temporary adhesive material for substrate processing; (b) A step of preheating one or both of the substrate and the support to a temperature of 30°C or higher and 100°C or lower; (c) A step of bringing the substrate and the support into contact with each other under reduced pressure via the temporary adhesive material and applying pressure at a pressure of 1 MPa or lower; (d) A step of heating the substrate temperature to a temperature of 130°C or higher and 250°C or lower while maintaining the applied pressure

[0017] With such a method for manufacturing a laminate, when joining a substrate having irregularities on its surface to a support via a temporary adhesive, a laminate can be manufactured without voids.

Effects of the Invention

[0018] As described above, in the case of the temporary adhesive material for substrate processing of the present invention, the temporary adhesion between the substrate and the support is easy, the process of forming the temporary adhesive layer on the substrate or the support is fast, and furthermore, it has excellent dimensional stability, excellent heat process resistance such as CVD (chemical vapor deposition), easy peeling, and can improve the productivity of the laminate. Also, when separating the substrate and the support after temporary adhesion, since separation is possible on the surface of the temporary adhesive layer or within the temporary adhesive layer, a through electrode structure and a thin substrate having a bump connection structure can be easily manufactured. Furthermore, for a substrate having a step, an adhesive layer with high film thickness uniformity can be formed, and due to this film thickness uniformity, it is possible to easily obtain a uniform laminate (such as a thin substrate) with a thickness of 50 μm or less. Moreover, after the laminate is produced, this substrate can be easily peeled from the support, for example, at room temperature, so that a laminate such as a thin substrate that is easily cracked can be easily manufactured.

Brief Description of the Drawings

[0019]

Figure 1

Embodiments for Carrying Out the Invention

[0020] As described above, there is a need for a temporary adhesive material for substrate processing that is easy to temporarily adhere, has a high speed of forming a temporary adhesive layer on the substrate or the support, has excellent dimensional stability, has excellent heat process resistance of the substrate such as CVD, is easy to peel, and can improve the productivity of thin substrates.

[0021] As a result of intensive studies to achieve the above object, the present inventors have found a temporary adhesive material for substrate processing for temporarily adhering a substrate to be processed on the back surface to a support, the temporary adhesive material contains 10 to 100 parts by mass of a siloxane bond-containing polymer having a weight average molecular weight of 3,000 or more and 700,000 or less as measured by gel permeation chromatography (GPC) with respect to 100 parts by mass of its total mass, the temporary adhesive material has a first temporary adhesive layer and a second temporary adhesive layer different from the first temporary adhesive layer, By using a temporary adhesive material for substrate processing, characterized in that at least one of the first temporary adhesive layer and the second temporary adhesive layer has a minimum value of shear viscosity in the range of 130°C or higher and 250°C or lower, and is 1 Pa·s or higher and 10,000 Pa·s or lower, preferably 5 Pa·s or higher and 8,000 Pa·s or lower, it has been found that a thin substrate having a through electrode structure or a bump connection structure can be easily manufactured, and the present invention has been completed.

[0022] Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto. In this specification, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are polystyrene conversion values using a calibration curve with standard polystyrene by gel permeation chromatography (GPC) method.

[0023] [Temporary Adhesive Material for Substrate Processing] The temporary adhesive material for substrate processing of the present invention is for temporarily adhering a substrate to be processed on the back surface to a support, and contains 10 parts by mass or more and 100 parts by mass or less of a siloxane bond-containing polymer having a weight average molecular weight measured by GPC of 3,000 or more and 700,000 or less with respect to 100 parts by mass of the total mass. The temporary adhesive material has a first temporary adhesive layer and a second temporary adhesive layer different from the first temporary adhesive layer, and at least one of the first temporary adhesive layer and the second temporary adhesive layer has a minimum value of shear viscosity in the range of 130°C or higher and 250°C or lower, and is 1 Pa·s or higher and 10,000 Pa·s or lower.

[0024] As shown in Fig. 1, the temporary adhesive material for substrate processing of the present invention has (A) a first temporary adhesive layer and (B) a second temporary adhesive layer different from the first temporary adhesive layer, and includes a substrate 1 to be processed on the back surface, a support 3 that supports the substrate 1 during processing of the substrate 1, and a temporary adhesive layer 2 interposed between the substrate 1 and the support 3. This temporary adhesive layer 2 has a two-layer structure of (A) a first temporary adhesive layer and (B) a second temporary adhesive layer. In Fig. 1, the first temporary adhesive layer is detachably adhered to the surface of the substrate 1, and the second temporary adhesive layer is detachably adhered to the surface of the support 3. Conversely, the first temporary adhesive layer may be detachably adhered to the surface of the support 3, and the second temporary adhesive layer may be detachably adhered to the surface of the substrate 1.

[0025] Further, the temporary adhesive material for substrate processing of the present invention contains 10 parts by mass or more and 100 parts by mass or less of the siloxane bond-containing polymer with respect to 100 parts by mass in total, and it is an essential condition that the minimum value of the shear viscosity of either or both of the first temporary adhesive layer and the second temporary adhesive layer is within the above range. With such a temporary adhesive material for substrate processing of the present invention, the adhesive forces between the substrate and the temporary adhesive layer, between the support and the temporary adhesive layer, and between the first temporary adhesive layer and the second temporary adhesive layer become appropriate. Therefore, when separating the substrate and the support after temporary adhesion, separation is possible on the surface of the temporary adhesive layer or within the temporary adhesive layer. Here, the surface of the temporary adhesive layer refers to the surface of the temporary adhesive layer detachably adhered to the substrate or the support (the adhesion surface between the substrate or the support and the temporary adhesive layer), and the inside of the temporary adhesive layer means the inside of the temporary adhesive layer and is not particularly limited. For example, it may be the adhesion surface between the first temporary adhesive layer and the second temporary adhesive layer. In addition, the shear viscosity in the present invention was determined by measuring the viscosity in the range of 130°C to 250°C by the method described in JIS K 7244. The minimum value of the shear viscosity of each layer is the minimum shear viscosity in the above temperature range.

[0026] [Laminate] As shown in FIG. 1, the laminate of the present invention is composed of a substrate 1 to be processed on the back surface, a support 3 that supports the substrate 1 during processing of the substrate 1, and an adhesive layer 2 interposed between the substrate 1 and the support 3. As described above, this adhesive layer 2 has a two-layer structure of (A) a first adhesive layer and (B) a second adhesive layer, and either may be on the substrate side.

[0027] [Temporary adhesive layer] The temporary adhesive layer has a two-layer structure of a first temporary adhesive layer and a second temporary adhesive layer different from the first temporary adhesive layer. This temporary adhesive layer contains 10 parts by mass or more and 100 parts by mass or less of the above siloxane bond-containing polymer with respect to 100 parts by mass of its total mass, and at least one of the first temporary adhesive layer and the second temporary adhesive layer has a minimum value of shear viscosity in the range of 130°C or more and 250°C or less, and is 1 Pa·s or more and 10,000 Pa·s or less. By having a shear viscosity in this range, a substrate having a step can be satisfactorily embedded with the temporary adhesive material. The temporary adhesive layer is not particularly limited as long as it satisfies the above conditions. When the content of the above siloxane bond-containing polymer is less than 10 parts by mass with respect to 100 parts by mass of the total mass of the temporary adhesive material, temporary adhesion and peeling are easy, the formation rate of the temporary adhesive layer on the substrate or the support is fast, and it will not become a temporary adhesive for substrate processing with excellent dimensional stability and excellent heat process resistance. Also, when the first temporary adhesive layer and the second temporary adhesive layer are not different, the peelability is poor, and when the minimum value of the shear viscosity of both the first temporary adhesive layer and the second temporary adhesive layer is less than 1 Pa·s or exceeds 10,000 Pa·s in the range of 130°C or more and 250°C or less, the adhesiveness is poor.

[0028] The material (resin) constituting each layer may be any as long as it satisfies the above conditions, and can be composed of a thermoplastic resin or a thermosetting resin. Hereinafter, the materials constituting each layer will be described.

[0029] [Thermoplastic resin] Among the temporary adhesive layers, the first temporary adhesive layer (A) can be composed of a thermoplastic resin. From the perspective of applicability to substrates with steps and the like, a thermoplastic resin having good embedability is preferably used as the material for forming the first temporary adhesive layer (A). In particular, a thermoplastic resin having no organopolysiloxane and a glass transition temperature of about -80 to 150 °C is preferred. For example, olefin-based thermoplastic elastomers, polybutadiene-based thermoplastic elastomers, styrene-based thermoplastic elastomers, styrene-butadiene-based thermoplastic elastomers, styrene-polyolefin-based thermoplastic elastomers, etc. can be mentioned. In particular, a hydrogenated polystyrene-based elastomer having excellent heat resistance is preferred.

[0030] As such thermoplastic resins, commercially available products can be used. Specifically, Tough Tech (Asahi Kasei Chemicals), Espolex SB series (Sumitomo Chemical), Ravaron (Mitsubishi Chemical), Septon (Kuraray), DYNARON (JSR), etc. can be mentioned. Also, cycloolefin polymers represented by Zeonex (Nippon Zeon) and cyclic olefin copolymers represented by TOPAS (Polyplastics Co., Ltd.) can be mentioned.

[0031] As described above, the thermoplastic resin of the first temporary adhesive layer (A) is preferably a thermoplastic elastomer. Also, two or more resins may be used in combination.

[0032] If it is such a material, after manufacturing the laminate (thin substrate, etc.), the temporary adhesive material can be peeled off and washed away from this substrate more easily, so that a thin and easily breakable substrate can be handled more easily.

[0033] The above thermoplastic resin (composition) can be dissolved in a solvent to form a temporary adhesive material solution and used for forming a temporary adhesive layer. Examples of the solvent include hydrocarbon solvents, preferably nonane, p-menthane, pinene, isooctane, mesitylene, etc. Among them, nonane, p-menthane, isooctane, and mesitylene are more preferred due to their coating properties. Further, filtration may be performed as necessary. Thereafter, it is preferably applied onto a support (release substrate), for example, using a forward roll coater, reverse roll coater, comma coater, die coater, lip coater, gravure coater, dip coater, air knife coater, capillary coater, raising & rising (R&R) coater, blade coater, bar coater, applicator, extrusion molding machine, etc. Then, the temporary adhesive layer is formed by removing the solvent from the support coated with the temporary adhesive material solution inline.

[0034] At this time, there is no restriction on the film thickness to be formed, but it is desirable to form a resin film (temporary adhesive layer) on the support. Preferably, it is formed with a film thickness of 0.5 to 80 μm, more preferably 0.5 to 50 μm. Further, for the purpose of improving the heat resistance of this thermoplastic resin, an antioxidant can be added, and for improving the coating properties, a surfactant can be added. As specific examples of the antioxidant, di-t-butylphenol, etc. are preferably used. As an example of the surfactant, a fluorosilicone-based surfactant X-70-1102 (manufactured by Shin-Etsu Chemical Co., Ltd.) etc. are preferably used. In the above, an example of forming the first temporary adhesive layer on the support has been described, but it may also be formed on a substrate to be processed on the back surface, or on the second temporary adhesive layer. Also, the lamination order of the first temporary adhesive layer and the second temporary adhesive layer may be reversed.

[0035] <Thermosetting resin> The temporary adhesive layer (the first temporary adhesive layer and the second temporary adhesive layer) can be composed of a thermosetting resin. As the thermosetting resin, a thermosetting resin mainly composed of a polymer containing a siloxane bond is preferable. In the present invention, the temporary adhesive layer contains 10 to 100 parts by mass of a polymer containing a siloxane bond having a weight average molecular weight of 3,000 or more and 700,000 or less as measured by GPC with respect to 100 parts by mass of the total mass. Although the polymer containing a siloxane bond is not particularly limited, a polymer composed of a thermosetting composition mainly composed of a thermosetting siloxane-modified polymer represented by the following general formula (1) and / or (3), or a polymer composed of a thermosetting composition mainly composed of an addition-curing type siloxane polymer can be used.

[0036] In addition, a polymer represented by the following general formula (1) and a polymer represented by the following general formula (3) can be used in combination in the temporary adhesive layer. In that case, the ratio (mass ratio) is preferably (1):(3) = 0.1:99.9 to 99.9:0.1, more preferably (1):(3) = 1:99 to 99:1.

[0037] Polymer of general formula (1) (phenolic siloxane polymer): It is a polymer containing a siloxane bond having a polystyrene-reduced weight average molecular weight of 3,000 to 500,000, preferably 10,000 to 100,000, as measured by gel permeation chromatography (GPC) and having a repeating unit represented by the following general formula (1).

Chemical formula

Chemical formula

[0038] In this case, specific examples of R 1 ~R 4 include a methyl group, an ethyl group, a phenyl group, etc. m is an integer of 1 to 100, preferably 3 to 60, more preferably 8 to 40. Also, B / A is greater than 0 and less than 20, particularly 0.5 to 5.)

[0039] Polymer of general formula (3) (epoxy-modified siloxane polymer): A siloxane bond-containing polymer having a polystyrene-reduced weight average molecular weight of 3,000 to 500,000 by GPC and having a repeating unit represented by the following general formula (3). [Chemical formula] [In the formula, R 7 ~R 10 represent monovalent hydrocarbon groups having 1 to 8 carbon atoms which may be the same or different. Also, n is an integer of 1 to 100, D is a positive number, and C is 0 or a positive number. Further, Y is a divalent organic group represented by the following general formula (4). C + D = 1. Also, preferably C is 0 to 0.9, D is 0.1 to 1, and when C is greater than 0, preferably C is 0.1 to 0.7 and D is 0.3 to 0.9.) [Chemical formula] (In the formula, V is [Chemical formula] a divalent organic group selected from any of the following, and p is 0 or 1. Also, R11 , R 12 is each an alkyl group or an alkoxy group having 1 to 4 carbon atoms, and they may be the same or different from each other. h is any one of 0, 1, and 2.)]

[0040] In this case, R 7 ~R 10 As specific examples of, those similar to those exemplified for R 1 ~R 4 in the general formula (1) above can be mentioned. Further, n is an integer of 1 to 100, preferably an integer of 3 to 60, more preferably an integer of 8 to 40. Also, D / C is greater than 0 and less than 20, particularly 0.5 to 5.

[0041] The thermosetting composition mainly composed of the thermosetting siloxane-modified polymer of the general formula (1) and / or (3) contains, for its thermosetting, in the case of the phenolic siloxane polymer of the general formula (1), an amino condensate modified with formalin or formalin-alcohol, a melamine resin, a urea resin, a phenolic compound having an average of 2 or more methylol groups or alkoxymethylol groups (alkoxymethyl group) in one molecule, and an epoxy compound having an average of 2 or more epoxy groups in one molecule. It can contain any one or more crosslinking agents selected from these.

[0042] Here, examples of the amino condensate modified with formalin or formalin-alcohol, the melamine resin, and the urea resin include the following. For example, as the melamine resin (condensate) modified with formalin or formalin-alcohol, a partial condensate of alkoxymethylol melamine such as hexamethoxymethylol melamine may be used, or a modified melamine monomer (for example, trimethoxymethyl monomethylol melamine), or a multimer thereof (for example, an oligomer such as a dimer or a trimer) can also be obtained by addition condensation polymerization with formaldehyde to a desired molecular weight according to a known method. Note that these can be used alone or in combination of two or more.

[0043] Also, the preparation of a urea resin (condensate) modified with formalin or formalin-alcohol may be carried out, for example, by methylolating a urea condensate of a desired molecular weight with formalin according to a known method and then modifying it, or further alkoxylating it with alcohol. Specific examples of the urea resin modified with formalin or formalin-alcohol include, for example, methoxymethylated urea condensate, ethoxymethylated urea condensate, propoxymethylated urea condensate, etc. Note that these can be used alone or in combination of two or more.

[0044] Also, examples of the phenol compound having on average two or more methylol groups or alkoxymethylol groups (alkoxymethyl group) in one molecule include (2-hydroxy-5-methyl)-1,3-benzenedimethanol, 2,2’,6,6’-tetramethoxymethyl bisphenol A, etc. Note that these phenol compounds can be used alone or in combination of two or more.

[0045] On the other hand, in the case of the epoxy-modified siloxane polymer of the general formula (3), one or more of an epoxy compound having on average two or more epoxy groups in one molecule or a phenol compound having on average two or more phenol groups in one molecule can be contained as a crosslinking agent.

[0046] Here, as the epoxy compound having a polyfunctional epoxy group used in the general formula (1), there is no particular limitation, but a bifunctional, trifunctional, tetrafunctional or higher polyfunctional epoxy resin, for example, EOCN-1020, EOCN-102S, XD-1000, NC-2000-L, EPPN-201, GAN, NC6000 manufactured by Nippon Kayaku Co., Ltd., or a crosslinking agent as shown in the following formula can be contained.

Chemical formula

[0047] Specific examples of the phenol compound having on average two or more phenol groups in one molecule as a crosslinking agent in the case where the thermosetting polymer is the epoxy-modified siloxane polymer of the general formula (3) include m, p-cresol novolak resins, for example, EP-6030G manufactured by Asahi Organic Chemical Industry Co., Ltd., trifunctional phenol compounds, for example, Tris-P-PA manufactured by Honshu Chemical Industry Co., Ltd., tetrafunctional phenol compounds, for example, TEP-TPA manufactured by Asahi Organic Chemical Industry Co., Ltd., and the like.

[0048] The blending amount of the crosslinking agent can be 0.1 to 50 parts by mass, preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, based on 100 parts by mass of the thermosetting polymer of the general formula (1) or formula (3), and two or more types may be mixed and blended.

[0049] Further, 10 parts by mass or less of a curing catalyst such as an acid anhydride may be contained based on 100 parts by mass of the thermosetting polymer.

[0050] The above-mentioned thermosetting resin (composition) can be dissolved in a solvent to form a temporary adhesive layer solution and used for forming the temporary adhesive layer. Examples of the solvent include ketones such as cyclohexanone, cyclopentanone, and methyl-2-n-amyl ketone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, propylene glycol mono-tert-butyl ether acetate, and γ-butyrolactone. These can be used alone or in combination of two or more. Further, filtration may be performed as necessary.

[0051] In addition, in order to further enhance the heat resistance, 50 parts by mass or less of a known antioxidant, a filler such as silica, etc. may be added based on 100 parts by mass of the thermosetting polymer. Further, in order to improve the coating uniformity, a surfactant may be added. Also, in order to improve the peelability, a peelability improver may be added.

[0052] Specific examples of the antioxidant that can be added to the temporary adhesive layer include hindered phenol-based compounds such as tetrakis[methylene-(3,5-di-t-butyl-4-hydroxyhydrocinnamate)]methane (trade name: Adeka Stab AO-60).

[0053] At this time, the film thickness formed is not particularly limited, but is preferably 5 to 150 μm, more preferably 10 to 120 μm. If the film thickness is 5 μm or more, it can sufficiently withstand the grinding process for thinning the substrate. If it is 150 μm or less, there is no risk of resin deformation in the heat treatment process such as the TSV formation process, and it can withstand practical use, which is preferable.

[0054] Addition-curable siloxane polymer: Further, the temporary adhesive layer can be an addition-curable siloxane polymer containing the following components (p1), (p2), and (p3).

[0055] (p1) Organopolysiloxane having an alkenyl group in the molecule: 100 parts by mass, (p2) Organohydrogenpolysiloxane containing hydrogen atoms (Si-H groups) bonded to two or more silicon atoms in one molecule: an amount such that the molar ratio of the Si-H groups in the component (p2) to the alkenyl groups in the component (p1) is 0.3 to 15. (p3) Platinum-based catalyst: more than 0 part by mass and 0.5 part by mass or less as the active ingredient (in terms of mass).

[0056] Hereinafter, each component will be described.

[0057] [Component (p1)] The component (p1) is an organopolysiloxane having an alkenyl group in the molecule. The component (p1) is preferably a linear or branched organopolysiloxane containing an alkenyl group having a molar ratio of the number of moles of alkenyl groups to the number of moles of Si (mole ratio of alkenyl groups / Si moles) in one molecule of 0.3 to 10 mol%. Particularly preferably, it is an organopolysiloxane containing an alkenyl group having a molar ratio of the number of moles of alkenyl groups to the number of moles of Si of 0.6 to 9 mol%.

[0058] Specific examples of such organopolysiloxane include those represented by the following formulas (5) and / or (6). R 13 (3-a) X 1a SiO-(R 13 X 1 SiO) l -(R 13 2SiO) r -SiR 13 (3-a) X 1 a (5) R 13 2(HO)SiO-(R 13 X 1 SiO) l+2 -(R 13 2SiO) r -SiR 13 2(OH) (6) (In the formula, each R 13 is independently a monovalent hydrocarbon group having no aliphatic unsaturated bond, and each X 1 is independently a monovalent organic group containing an alkenyl group, and a is an integer of 0 to 3. In formula (5), 2a + 1 is a number such that the alkenyl group content in one molecule is 0.3 to 10 mol%. In formula (6), 1 + 2 is a number such that the alkenyl group content in one molecule is 0.3 to 10 mol%. 1 is 0 or a positive number of 500 or less, and r is a positive number of 1 to 10,000.)

[0059] In the above formula, as R 13 , a monovalent hydrocarbon group having 1 to 10 carbon atoms and no aliphatic unsaturated bond is preferable. For example, alkyl groups such as methyl group, ethyl group, propyl group, and butyl group; cycloalkyl groups such as cyclohexyl group; aryl groups such as phenyl group and tolyl group, etc. Among them, alkyl groups such as methyl group or phenyl group are particularly preferable.

[0060] X 1As the alkenyl group-containing monovalent organic group, an organic group having 2 to 10 carbon atoms is preferable, and examples thereof include alkenyl groups such as vinyl group, allyl group, hexenyl group, and octenyl group; (meth)acryloylalkyl groups such as acryloylpropyl group, acryloylmethyl group, and methacryloylpropyl group; (meth)acryloxyalkyl groups such as acryloxypropyl group, acryloxy methyl group, methacryloxypropyl group, and methacryloxy methyl group; and alkenyl group-containing monovalent hydrocarbon groups such as cyclohexenylethyl group and vinyloxypropyl group. Particularly, industrially, a vinyl group is preferable.

[0061] In the above general formula (5), a is an integer of 0 to 3. When a is 1 to 3, since the molecular chain end is blocked by an alkenyl group, the reaction can be completed in a short time due to this highly reactive molecular chain end alkenyl group, which is preferable. Further, from the cost aspect, a = 1 is industrially preferable. The property of this alkenyl group-containing organopolysiloxane is preferably oily or raw rubber-like. This alkenyl group-containing organopolysiloxane may be linear or branched. Also, two or more kinds of the (p1) component may be used in combination.

[0062] In addition, the number average molecular weight (Mn) of the above (p1) component by GPC is preferably 100,000 to 500,000.

[0063] [(p2) component] The (p2) component is a crosslinking agent and is an organohydrogenpolysiloxane containing hydrogen atoms (Si-H groups) bonded to two or more silicon atoms in one molecule. The (p2) component has at least two, preferably two or more and 100 or less, more preferably three or more and 50 or less hydrogen atoms (SiH groups) bonded to silicon atoms in one molecule, and linear, branched, or cyclic ones can be used.

[0064] (p2) The viscosity of the organohydrogenpolysiloxane component at 25°C is preferably from 1 to 5,000 mPa·s, more preferably from 5 to 500 mPa·s. This organohydrogenpolysiloxane may be a mixture of two or more kinds. The viscosity is measured by a rotational viscometer.

[0065] (p2) The component is formulated such that the molar ratio of the Si-H groups in the (p2) component to the alkenyl groups in the (p1) component (Si-H groups / alkenyl groups) is in the range of 0.3 to 15, preferably 0.3 to 10, particularly preferably 1 to 8. When the molar ratio of this SiH group to the alkenyl group is 0.3 or more, there is no fear that the crosslinking density will be low, and there is no problem that the adhesive layer will not harden, which is preferable. If it is 15 or less, there is no fear that the crosslinking density will become too high, and sufficient adhesive strength and tack can be obtained.

[0066] [(p3) component] (p3) The component is a platinum-based catalyst (that is, a platinum group metal catalyst), and examples thereof include chloroplatinic acid, an alcohol solution of chloroplatinic acid, a reaction product of chloroplatinic acid and alcohol, a reaction product of chloroplatinic acid and an olefin compound, and a reaction product of chloroplatinic acid and a vinyl group-containing siloxane.

[0067] (p3) The addition amount of the component is an effective amount, and is usually 1 to 5,000 ppm, preferably 5 to 2,000 ppm, in terms of platinum content (mass conversion) based on the total of (p1) and (p2). If it is 1 ppm or more, the curability of the composition will not decrease, the crosslinking density will not decrease, and the holding power will not decrease. If it is 5,000 ppm or less, the usable time of the treatment liquid can be lengthened.

[0068] The above-mentioned thermosetting siloxane polymer layer composition can be dissolved in a solvent to form a temporary adhesive layer solution and used for forming a temporary adhesive layer. As the solvent, for example, hydrocarbon solvents such as pentane, hexane, cyclohexane, isooctane, nonane, decane, p-menthane, pinene, isododecane, limonene, and volatile low-molecular siloxanes such as hexamethyldisiloxane and octamethyltrisiloxane are preferably used, and one of these can be used alone or two or more can be used in combination. In addition, a known antioxidant can be added to this thermosetting siloxane polymer layer composition to improve heat resistance. Furthermore, filtration may be performed as necessary.

[0069] At this time, the film thickness formed is preferably between 0.1 and 30 μm, particularly preferably between 1.0 and 15 μm. If the film thickness is 0.1 μm or more, peeling from the substrate or support becomes even easier. On the other hand, if the film thickness is 30 μm or less, it can sufficiently withstand the grinding process when forming a thin wafer. In addition, in order to further enhance the heat resistance of this thermosetting siloxane polymer layer, a filler such as silica may be added in an amount of 50 parts by mass or less based on a total of 100 parts by mass of the components (p1), (p2), and (p3) of the thermosetting siloxane polymer mixed together.

[0070] [Method for manufacturing a laminate] The method for manufacturing the laminate of the present invention has steps (a) to (d). [Step (a)] Step (a) is a step of forming a temporary adhesive layer on the surface to be joined of either one or both of the substrate and the support using the temporary adhesive material for substrate processing of the present invention.

[0071] The substrate to be processed is, for example, a substrate having one surface as a circuit formation surface and the other surface (back surface) to be processed as a non-circuit formation surface. The substrate to which the present invention can be applied is usually a semiconductor substrate. Examples of the semiconductor substrate include a disk-shaped wafer, a square substrate, etc. Examples of the wafer include not only a silicon wafer but also a germanium wafer, a gallium-arsenide wafer, a gallium-phosphorus wafer, a gallium-arsenide-aluminum wafer, etc. The thickness of the substrate is not particularly limited, but typically it is 600 to 800 μm, more typically 625 to 775 μm.

[0072] Particularly in the method for manufacturing the laminate (such as a thin wafer) of the present invention, a substrate having steps due to circuits on its surface is effective, and in particular, a substrate having steps of 10 to 80 μm, preferably 20 to 70 μm is effective.

[0073] The support is not particularly limited, but substrates such as a silicon wafer, a glass plate, and a quartz wafer can be used. In the present invention, it is not necessarily required to irradiate the temporary adhesive layer with radiant energy rays through the support, and the support may not have light transmissibility.

[0074] The first temporary adhesive layer and the second temporary adhesive layer are each a film and can be formed on a substrate (wafer) or a support, or the respective solutions can be formed on a wafer or a support by a method such as spin coating or roll coating. In this case, after spin coating, depending on the solvent volatilization conditions, heat treatment is performed in advance at a temperature of 80 to 200 °C, preferably 100 to 180 °C, and then it is used. The first temporary adhesive layer and the second temporary adhesive layer can be formed on both the substrate or the support, or only one of them can be formed on either the substrate or the support. Examples of the method for forming the temporary adhesive layer are given below.

[0075] [Formation Method 1] The first temporary adhesive layer is formed on the support using the solution of the first temporary adhesive layer, and then the second temporary adhesive layer is formed on the formed first temporary adhesive layer using the solution of the second temporary adhesive layer.

[0076] [Forming Method 2] A first temporary adhesive layer is formed on a support using a solution of the first temporary adhesive layer. Separately, a second temporary adhesive layer is formed on a substrate using a solution of the second temporary adhesive layer.

[0077] Also, when each adhesive layer is formed of a film, the components of the present invention can be formed on a protective film such as polyethylene or polyester, and the protective film can be peeled off and used.

[0078] Steps (b) to (d) are steps of bonding the substrate and the support. Examples of the substrate bonding device include commercially available wafer bonding devices such as EVG520IS, 850TB of EVG and XBS300 of SUSS in the case of wafers. The substrate and the support may be arranged in the apparatus so that they can be bonded via the temporary adhesive material. For example, when the first temporary adhesive layer and the second temporary adhesive layer are formed on the support as in the above forming method 1, the surface of the substrate on which the temporary adhesive layer is to be formed and the surface of the support on which the temporary adhesive layer is formed are opposed to each other. Also, when the first temporary adhesive layer or the second temporary adhesive layer is formed on each of the substrate or the support as in the above forming method 2, the surface of the substrate on which the temporary adhesive layer is formed and the surface of the support on which the temporary adhesive layer is formed are opposed to each other and can be arranged in the apparatus.

[0079] [Step (b)] Step (b) is a step of preheating either one or both of the substrate and the support. In this case, the heating means is built into the bonding apparatus, and a heater is built into the plate (chamber) on which the substrate and the support are installed. The heater may be any known heating device. Either one or both of the substrate and the support are heated to a temperature of 30°C or higher and 100°C or lower.

[0080] [Step (c)] Step (c) is a step of bringing the substrate into contact with the support under reduced pressure via an interim adhesive material and applying pressure at a pressure of 1 MPa or less. For example, under vacuum (reduced pressure; pressure of 1 Pa or less) at the temperature condition heated in step (b), pressure is applied to this substrate uniformly at a pressure of 1 MPa or less. At this time, the time for applying pressure is from 10 seconds to 10 minutes, preferably from 30 seconds to 5 minutes.

[0081] [Step (d)] Step (d) is a step of heating the substrate temperature to a temperature of 130°C or higher and 250°C or lower while maintaining the pressure applied in step (c). The time for maintaining at this time is from 10 seconds to 10 minutes, preferably from 30 seconds to 5 minutes.

[0082] For a laminate obtained through the above steps (a) to (d) using the interim adhesive material of the present invention, at least one of the first interim adhesive layer and the second interim adhesive layer has a minimum value of shear viscosity in the range of 130°C or higher and 250°C or lower, and is 1 Pa·s or more and 10,000 Pa·s or less. Therefore, a substrate having a step can be satisfactorily embedded with the interim adhesive material.

Example

[0083] Hereinafter, the present invention will be described more specifically by showing examples and comparative examples, but the present invention is not limited to these examples. In the following examples, "parts" are parts by mass. Further, Me represents a methyl group and Vi represents a vinyl group. Compounds (M-1) to (M-5) used in the following resin solution preparation examples are shown below.

[0084]

Chemical formula

[0085] [Resin solution preparation example 1] 24 g of the thermoplastic resin Septon 4033 (containing 30% styrene, manufactured by Kuraray), which is a hydrogenated styrene-isoprene-butadiene copolymer, was dissolved in 176 g of isononane to obtain an isononane solution of a 12 mass% hydrogenated styrene-isoprene-butadiene copolymer. The resulting solution was filtered through a 0.2 μm membrane filter to obtain an isononane solution (A-1) of the thermoplastic resin.

[0086] [Production Example 2 of Resin Solution] 30 g of the thermoplastic resin Septon 4044 (containing 32% styrene, manufactured by Kuraray), which is a hydrogenated styrene-isoprene-butadiene copolymer, was dissolved in 176 g of isononane to obtain an isononane solution of a 12 mass% hydrogenated styrene-isoprene-butadiene copolymer. The resulting solution was filtered through a 0.2 μm membrane filter to obtain an isononane solution (A-2) of the thermoplastic resin.

[0087] [Production Example 3 of Resin Solution] Into a flask equipped with a stirrer, a thermometer, a nitrogen replacement device, and a reflux condenser, 43.1 g of 9,9'-bis(3-allyl-4-hydroxyphenyl)fluorene (M-1), 29.5 g of organohydridosiloxane represented by the average structural formula (M-3), 135 g of toluene, and 0.04 g of chloroplatinic acid were charged, and the temperature was raised to 80°C. Then, 17.5 g of 1,4-bis(dimethylsilyl)benzene (M-5) was added dropwise into the flask over 1 hour. At this time, the temperature inside the flask rose to 85°C. After the addition was completed, it was further aged at 80°C for 2 hours, then toluene was distilled off, and 80 g of cyclohexanone was added to obtain a resin solution having a resin solid content concentration of 50% by mass and using cyclohexanone as a solvent. When the molecular weight of the resin component in this solution was measured by GPC, the weight average molecular weight was 45,000 in terms of polystyrene. Further, to 50 g of this resin solution, 7.5 g of EOCN-1020 (manufactured by Nippon Kayaku Co., Ltd.), an epoxy crosslinking agent, as a crosslinking agent, 0.2 g of BSDM (bis(tert-butylsulfonyl)diazomethane) manufactured by Wako Pure Chemical Industries, Ltd. as a curing catalyst, and further 0.1 g of tetrakis[methylene-(3,5-di-t-butyl-4-hydroxyhydrocinnamate)]methane (trade name: Adeka Stab AO-60) as an antioxidant, and 0.1 g of KF-54 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a peel improvement agent were added, and it was filtered through a 1-μm membrane filter to obtain a resin solution (B-1). The elastic modulus measured by dynamic viscoelasticity measurement of the (B-1) cured film was 300 MPa at 25°C.

[0088] [Preparation Example 4 of Resin Solution] 84.1 g of an epoxy compound (M-2) was dissolved in 600 g of toluene in a 5 L flask equipped with a stirrer, a thermometer, a nitrogen replacement device, and a reflux condenser. Then, 294.6 g of compound (M-3) and 25.5 g of compound (M-4) were added, and the mixture was heated to 60°C. Thereafter, 1 g of a carbon-supported platinum catalyst (5 mass%) was added. After confirming that the internal reaction temperature rose to 65 - 67°C, it was further heated to 90°C and aged for 3 hours. Next, after cooling to room temperature, 600 g of methyl isobutyl ketone (MIBK) was added, and the platinum catalyst was removed by pressure filtration of the reaction solution through a filter. The solvent in this resin solution was distilled off under reduced pressure, and 270 g of propylene glycol monomethyl ether acetate (PGMEA) was added to obtain a resin solution having a solid content concentration of 60 mass% with PGMEA as the solvent. When the molecular weight of the resin in this resin solution was measured by GPC, it was 28,000 in terms of polystyrene conversion weight average molecular weight. Further, 9 g of TEP-TPA (manufactured by Asahi Organic Materials Co., Ltd.), a tetrafunctional phenol compound, 0.2 g of tetrahydrophthalic anhydride (manufactured by Shin Nippon Rika Co., Ltd., Rica Sid HH-A), and 0.1 g of KF-54 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a peel improvement agent were added to 100 g of this resin solution, and the mixture was filtered through a 1 μm membrane filter to obtain a resin solution (B-2). The elastic modulus measured by dynamic viscoelasticity measurement of the cured film of (B-2) was 500 MPa at 25°C.

[0089] [Preparation Example 5 of Resin Solution] To a solution composed of 100 parts of a polydimethylsiloxane having 3 mol% of vinyl groups at both ends and side chains and a molecular end blocked with a SiMe2Vi group and having a number average molecular weight (Mn) of 50,000 by GPC and 400 parts of isododecane, 5 parts (2 mol with respect to the alkenyl group) of an organohydropolysiloxane represented by the following formula (M-6) was added and mixed. Further, 0.05 part of a platinum catalyst CAT-PL-5 (manufactured by Shin-Etsu Chemical Co., Ltd.) was added to 100 parts of polydimethylsiloxane, and the mixture was filtered through a 0.2 μm membrane filter to obtain a thermosetting siloxane polymer solution (C-1). [Chemical Formula]

[0090] [Preparation Example 6 of Resin Solution] 100 parts of a polydimethylsiloxane having 3 mol% vinyl groups at both ends and side chains, with the molecular terminals blocked by SiMe2Vi groups and a number average molecular weight (Mn) of 50,000 by GPC, and 400 parts of isododecane were mixed by adding 10 parts (2 mol with respect to the alkenyl group) of an organohydrogenpolysiloxane represented by the following formula (M-7). Further, 0.05 part of a platinum catalyst CAT-PL-5 (manufactured by Shin-Etsu Chemical Co., Ltd.) was added to 100 parts of polydimethylsiloxane, and the mixture was filtered through a 0.2 μm membrane filter to obtain a thermosetting siloxane polymer solution (C-2). [Chemical Formula]

[0091] [Example 1] After spin-coating the above solution (C-1) on a 200 mm diameter glass wafer and heating it on a hot plate, a material corresponding to the (C) layer was formed into a film. Subsequently, after spin-coating the above solution (B-1) on the (C) layer of the glass wafer on which the (C) layer was formed and heating it on a hot plate, a material corresponding to the (B) layer was formed into a film ((a) step). The film formation order, heating conditions, and film thickness are shown in Table 1. In addition, the "amount of siloxane bond-containing polymer" in Table 1 is the mass part of the siloxane bond-containing polymer having a weight average molecular weight measured by GPC of 3,000 or more and 700,000 or less with respect to 100 parts of the total mass of the temporary adhesive material.

[0092] The copper post surface of a silicon wafer with a diameter of 200 mm and a thickness of 725 μm, on which copper posts with a height of 40 μm and a diameter of 40 μm are formed on the entire surface, is opposed to the surface of the glass wafer on which the temporary adhesive layer was formed in the (a) process, and is pre-heated to 70 °C in a bonding apparatus ((b) process). Subsequently, in the bonding apparatus, the silicon wafer and the glass wafer are brought into contact under reduced pressure and pressurized at a pressure of 0.5 MPa ((c) process). Further, while maintaining the pressure, the substrate temperature is heated to 150 °C, and pressurization is continued for 3 minutes after reaching 150 °C ((d) process) to fabricate a laminate. The conditions from (b) to (d) are shown in Table 3.

[0093] [Examples 2 to 4 and Comparative Example 1] Under the conditions described in Table 1 and Table 3, Examples 2 to 4 and Comparative Example 1 were also processed in the same manner as Example 1.

[0094] - Viscosity measurement - Under the conditions of Example 1, after spin-coating the above (C-1) solution on a 200 mm diameter silicon wafer and heating it on a hot plate, a material corresponding to the (C) layer was formed into a film. On the other hand, after spin-coating the above (B-1) solution on a 200 mm diameter silicon wafer and heating it on a hot plate, a material corresponding to the (B) layer was formed into a film. Then, each temporary adhesive layer was peeled off from the silicon wafer to obtain two temporary adhesive films. Viscosity measurements were performed on each film in the range of 130 °C to 250 °C by the method described in JIS K 7244. The lower viscosity value among the minimum viscosities of the two temporary adhesive films is shown in Table 1. Similarly, Examples 2 to 4 and Comparative Example 1 were also measured in the same manner as Example 1, and the results are shown in Table 1.

[0095] [Example 5] After spin-coating the above solution (C-2) on a glass wafer with a diameter of 200 mm and heating it on a hot plate, a material corresponding to the (C) layer was formed. On the other hand, the above solution (B-1) was spin-coated on the copper post surface of a silicon wafer with a diameter of 200 mm and a thickness of 725 μm, on which copper posts with a height of 40 μm and a diameter of 40 μm were formed on the entire surface, and then heated on a hot plate to form a material corresponding to the (B) layer (step (a)). The heating conditions and film thickness are shown in Table 2.

[0096] (b) Step: The surface of the silicon wafer with a diameter of 200 mm and a thickness of 725 μm, on which copper posts with a height of 40 μm and a diameter of 40 μm were formed on the entire surface, produced in step (a) and having a temporary adhesive layer formed thereon, was opposed to the surface of the glass wafer having a temporary adhesive layer formed thereon, and the two were pre-heated to 70 °C in a bonding apparatus. Subsequently, in the bonding apparatus, the silicon wafer and the glass wafer were brought into contact with each other under reduced pressure and pressurized at a pressure of 0.5 MPa (step (c)). Further, while maintaining the pressure, the substrate temperature was heated to 140 °C, and pressurization was continued for 3 minutes after reaching 140 °C (step (d)) to produce a laminate. The conditions from (b) to (d) are shown in Table 3.

[0097] [Examples 6 to 7 and Comparative Example 2] Examples 6 to 7 and Comparative Example 2 were also processed in the same manner as Example 5 under the conditions described in Table 2 and Table 3.

[0098] - Viscosity measurement - Under the conditions of Example 5, after spin-coating the above (C-2) solution on a silicon wafer with a diameter of 200 mm and heating it on a hot plate, a material corresponding to the (C) layer was formed into a film. On the other hand, after spin-coating the above (B-1) solution on a silicon wafer with a diameter of 200 mm and heating it on a hot plate, a material corresponding to the (B) layer was formed into a film. Then, the temporary adhesive layer was peeled off from the silicon wafer to obtain two temporary adhesive films. The viscosity of these films was measured in the range of 130°C to 250°C by the method described in JIS K 7244. Among the minimum viscosity values of the two temporary adhesive films, the lower viscosity value is shown in Table 2. Similarly, Examples 6 to 7 and Comparative Examples 2 and 3 were also measured in the same manner as Example 5, and the results are shown in Table 2. In addition, the "amount of siloxane bond-containing polymer" in Tables 1 and 2 is the mass part of the siloxane bond-containing polymer whose weight average molecular weight measured by GPC is 3,000 or more and 700,000 or less with respect to 100 parts by mass of the total mass of the temporary adhesive material.

[0099] Here, a glass plate was used as a support for visually discriminating abnormalities after substrate bonding. However, a silicon substrate that does not transmit light, such as a wafer, can also be used.

[0100] The following test was performed on this bonded substrate (sample), and the results of the examples and comparative examples are shown in Table 4. In addition, the evaluation was carried out in the following order. However, when the determination in the evaluation was "×", the subsequent evaluations were aborted.

[0101] - Adhesion test - The laminate was heat-treated at 180°C for 1 hour using an oven and then cooled to room temperature, and the adhesion status of the interface was visually confirmed. When no abnormalities such as bubbles occurred at the interface, it was evaluated as good and indicated by "○", and when abnormalities occurred, it was evaluated as bad and indicated by "×".

[0102] - Back grinding resistance test - Using a grinder (manufactured by DISCO Corporation, model DAG810) with a diamond grinding wheel, the backside of a silicon wafer was ground for the laminate (sample) obtained by heat curing at 180 °C for 1 hour in an oven as described above. After grinding to a final substrate thickness of 50 μm, the presence or absence of abnormalities such as cracks and delamination was examined using an optical microscope (100x magnification). The case where no abnormalities occurred was indicated by "○", and the case where abnormalities occurred was indicated by "×".

[0103] -CVD Resistance Test- After backside grinding of the silicon wafer, the processed body was introduced into a CVD apparatus, and an experiment for forming a 2-μm SiO2 film was conducted, and the presence or absence of appearance abnormalities was examined. The case where no appearance abnormalities occurred was indicated by "○", and the case where voids, wafer swelling, wafer breakage, etc. occurred was indicated by "×". The conditions for the CVD resistance test are as follows. Apparatus name: Plasma CVD PD270STL (manufactured by SAMCO, Inc.) RF 500 W, internal pressure 40 Pa TEOS (tetraethyl orthosilicate) : O2 = 20 sccm : 680 sccm

[0104] -Peelability Test- The peelability of the substrate was evaluated by the following method. First, a dicing tape was attached to the wafer side thinned to 50 μm of the wafer processed body after the CVD resistance test using a dicing frame, and this dicing tape surface was set on a suction plate by vacuum suction. Then, at room temperature, the glass substrate was peeled off by lifting a point of the glass with tweezers. The case where the 50-μm wafer could be peeled off without cracking was indicated by "○", and the case where abnormalities such as cracking occurred was evaluated as defective and indicated by "×".

[0105]

Table 1

[0106]

Table 2

[0107]

Table 3

[0108]

Table 4

[0109] As shown in Table 4, it was found that in the temporary adhesive material satisfying the requirements of the present invention, the temporary adhesion between the substrate and the support is easy, and the peeling is also easy (Examples 1 to 7). On the other hand, in Comparative Examples 1 and 2 that do not satisfy the requirements of the present invention, there were problems with adhesiveness and peelability. In particular, in Comparative Example 2 where the first temporary adhesive layer and the second temporary adhesive layer are not different even though the range of the shear viscosity of the temporary adhesive layer is within the range of the present invention, the peelability deteriorated.

[0110] Note that the present invention is not limited to the above-described embodiments. The above-described embodiments are examples, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits the same operational effects is included in the technical scope of the present invention.

Explanation of Reference Numerals

[0111] 1... Substrate, 2... Temporary adhesive layer, (A)... First temporary adhesive layer, (B)... Second temporary adhesive layer, 3... Support.

Claims

1. A temporary bonding material for substrate processing for temporarily bonding a substrate to be processed on its back surface to a support, wherein the temporary bonding material contains 10 to 100 parts by mass of a siloxane bond-containing polymer having a weight average molecular weight of 3,000 or more and 700,000 or less as measured by GPC based on 100 parts by mass of the total mass, the temporary bonding material has a two-layer structure of a first temporary bonding material layer and a second temporary bonding material layer different from the first temporary bonding material layer, and the first temporary bonding material layer is composed of a thermoplastic elastomer having a glass transition temperature of -80 to 150°C and not having organopolysiloxane, the second temporary bonding material layer has a minimum value of shear viscosity in the range of 130°C or higher and 250°C or lower, and is 4,000 Pa·s or more and 10,000 Pa·s or less, the siloxane bond-containing polymer is, (p1) an organopolysiloxane represented by the following formula (5) having an alkenyl group in the molecule, R 13 (3-a) X 1 a SiO-(R 13 X 1 SiO) l -(R 13 2 SiO) r -SiR 13 (3-a) X 1 a (5) (In the formula, each R 13 is independently a methyl group, each X 1 is independently a vinyl group, and a is an integer of 1 to 3. 2a + l is a number such that the alkenyl group content in one molecule is 0.3 to 10 mol%. l is a positive number of 500 or less, and r is a positive number of 1 to 10,000.) (p2) an organohydropolysiloxane containing hydrogen atoms (Si-H groups) bonded to two or more silicon atoms in one molecule: the molar ratio of the Si-H groups in the (p2) component to the alkenyl groups in the (p1) component is an amount of 0.3 to 15, and (p3) a platinum-based catalyst, and is characterized by containing these. A temporary bonding material for substrate processing.

2. A laminate composed of a substrate, a support, and a temporary bonding material interposed between the substrate and the support, wherein the temporary bonding material is the temporary bonding material for substrate processing according to Claim 1, and has a two-layer structure of a first temporary bonding material layer and a second temporary bonding material layer different from the first temporary bonding material layer, the second temporary bonding material layer is formed on the surface of the support, and the second temporary bonding material layer contains the (p1), (p2), and (p3) as the siloxane bond-containing polymer. A laminate characterized by this.

3. A method for manufacturing a laminate for bonding a substrate and a support via a temporary bonding material, The temporary adhesive material has a two-layer structure composed of a first temporary adhesive layer and a second temporary adhesive layer different from the first temporary adhesive layer. A method for manufacturing a laminate, comprising the following steps (a) to (d). (a) A step of forming a temporary adhesive layer on either one or both of the bonding surfaces of the substrate and the support using the temporary adhesive material for substrate processing according to claim 1, including forming the second temporary adhesive layer using a siloxane bond-containing polymer containing the (p1), (p2), and (p3) on at least the support. (b) A step of preheating either one or both of the substrate and the support to a temperature of 30°C or higher and 100°C or lower. (c) A step of bringing the substrate and the support into contact with each other under reduced pressure through the temporary adhesive material and applying pressure at a pressure of 1 MPa or lower. (d) A step of heating the substrate temperature to a temperature of 130°C or higher and 250°C or lower while maintaining the applied pressure.

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