JP2013110352A - Processing method of base material, semiconductor device, and composition for temporary fixture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a processing method of a base material which prevents the permeability of infrared rays from deteriorating due to temperature rise of a support medium and efficiently peels the base material from the support medium in a peeling process of the base material using the infrared rays.SOLUTION: A processing method of a base material includes the steps of: (1) temporarily fixing a support medium, formed by a base material and a silicon wafer, through a temporary fixing material having a photothermal conversion layer; (2) processing the base material; (3) radiating infrared rays to the temporary fixing material from the support medium side without focusing on a surface opposite to a contact surface of the support medium, contacting with the temporary fixing material; and (4) peeling the base material from the support medium.

Description

  The present invention relates to a substrate processing method using a temporary fixing material, a semiconductor device obtained by the processing method, and a temporary substrate used for temporarily fixing the substrate on a support when the substrate is processed. The present invention relates to a raw material composition suitable for forming a fixing material.

  When processing a substrate such as a semiconductor wafer (eg, backside grinding, photofabrication), temporarily fix the substrate and support using a temporary fixing material, etc. so that the substrate does not move due to displacement from the support. There is a need to. And after completion | finish of a process, it is necessary to peel a base material from a support body.

  In the peeling treatment, by irradiating the irradiated body composed of the support / temporary fixing material / substrate with radiation energy such as ultraviolet rays and infrared rays, the adhesive force of the temporary fixing material is reduced, and the substrate is removed from the support. Several methods of peeling have been proposed.

  For example, Patent Document 1 provides a laminate including a substrate to be ground, a bonding layer in contact with the substrate to be ground, a photothermal conversion layer, and a light-transmitting support, and the substrate to be ground To a desired thickness, irradiate the photothermal conversion layer with radiant energy through the light transmissive support, disassemble the photothermal conversion layer, and the ground substrate and the light transmissive support. A method for producing a thinned substrate is disclosed, which includes the steps of separating and peeling the bonding layer from the ground substrate. In the said method, a glass plate and an acrylic board are mentioned as a light-transmissive support body.

JP 2004-064040 A

  In Patent Document 1, it is assumed that a glass plate such as Pyrex (trade name) is used as a light-transmitting support from the viewpoint of transmittance. However, the glass plate has low versatility and is considered disadvantageous in terms of yield. The present inventors examined the use of a silicon wafer as a support. There is no example of using a silicon wafer as a support in the temporary fixing / peeling process of the substrate as described above.

  However, when a silicon wafer is used as a support in a substrate peeling process using infrared rays such as an infrared laser, when the silicon wafer is irradiated with infrared rays, the infrared rays transmittance is significantly reduced due to the temperature rise, and temporary Infrared rays do not reach the fixing material. As a result, the substrate cannot be peeled from the support.

  The subject of this invention is the processing method of the base material which solved the above-mentioned problem in the peeling process of the base material using infrared rays, the semiconductor device obtained by the said processing method, and the temporarily fixed material used suitably for the said processing method The object is to provide a raw material composition (composition for temporary fixing).

  The present inventors have intensively studied to solve the above problems. As a result, the infrared focal point of the infrared laser or the like is removed from the surface opposite to the contact surface of the silicon wafer as a support with respect to the temporary fixing material, thereby preventing a decrease in infrared transmittance due to the temperature rise of the silicon wafer. As a result, the present invention has been completed. That is, the present invention relates to the following [1] to [7], for example.

[1] (1) A step of temporarily fixing a base material and a support made of a silicon wafer via a temporary fixing material having a photothermal conversion layer, (2) a step of processing the base material, (3) the support Irradiating the temporary fixing material with infrared rays from the support side without focusing on the surface of the body opposite to the contact surface with respect to the temporary fixing material, and (4) the base material from the support body. The processing method of a base material which has the process to peel.
[2] The method for treating a substrate according to [1], wherein in the step (3), the infrared ray is an infrared laser.
[3] The substrate processing method according to [2], wherein in the step (3), the temporary fixing material is irradiated from the support side while scanning with an infrared laser.
[4] The substrate processing method according to [2] or [3], wherein in the step (3), an infrared laser is focused on the photothermal conversion layer.
[5] In the step (1), the substrate, the support made of the silicon wafer, and the support, the photothermal conversion layer, the adhesive layer, and the substrate are interposed via the temporary fixing material having the adhesive layer and the photothermal conversion layer. The substrate processing method according to any one of [1] to [4], wherein the substrate is temporarily fixed so as to be a laminated body having layers in the order of materials.
[6] A temporary fixing composition for forming a photothermal conversion layer of a temporary fixing material, comprising a cycloolefin polymer and carbon black.
[7] A semiconductor device obtained by the substrate processing method according to any one of [1] to [5].

  According to the present invention, in the substrate peeling process using infrared rays, it is possible to prevent a decrease in the transmittance of infrared rays due to the temperature rise of the silicon wafer that is the support, and thus the substrate is efficiently removed from the silicon wafer that is the support. To provide a substrate processing method capable of peeling a material, a semiconductor device obtained by the processing method, and a temporary fixing material composition (temporary fixing composition) suitably used in the processing method Can do.

  In the present invention, the temporary fixing material is used to temporarily fix the base material so that the base material is not displaced from the support when the base material such as a semiconductor wafer is processed (eg, back grinding, photofabrication). It refers to the temporary fixing material used. Examples of photofabrication include formation of resist patterns, formation of metal bumps by plating, film formation by chemical vapor deposition, and processing by reactive ion etching.

  The substrate processing method of the present invention includes (1) a step of temporarily fixing a substrate and a support made of a silicon wafer via a temporary fixing material having a photothermal conversion layer, and (2) processing the substrate. (3) irradiating the temporary fixing material with infrared rays from the side of the support without focusing on the surface opposite to the contact surface of the support with respect to the temporary fixing material, and (4) A step of peeling the substrate from the support. Hereinafter, each of the steps is also referred to as “step (1)” to “step (4)”.

  In this way, by irradiating the irradiated object without focusing on the surface opposite to the contact surface of the support with respect to the temporary fixing material of the support, the temperature of the silicon wafer as the support increases, and thus A decrease in infrared transmittance can be suppressed. Therefore, the substrate can be efficiently peeled from the support. For example, peeling can be performed more efficiently by irradiating an infrared laser focused on the photothermal conversion layer. In this invention, since a base material can be favorably peeled from a support body by infrared irradiation, the base material which is a workpiece is not damaged.

  The temporary fixing material preferably has a photothermal conversion layer and an adhesive layer. That is, in the step (1), the base material and the support made of the silicon wafer are bonded to the support, the light-heat conversion layer, the adhesive layer, and the base material via a temporary fixing material having the adhesive layer and the light-heat conversion layer. It is preferable to temporarily fix the laminated body having the respective layers in order, that is, the layer configuration to be the support / photothermal conversion layer / adhesive layer / base material.

  By temporarily fixing the substrate with such a layer structure of support / photothermal conversion layer / adhesive layer / base (that is, the temporary fixing material is composed of the photothermal conversion layer and the adhesive layer), the support / Compared to the case where the substrate is temporarily fixed in the layer configuration of the photothermal conversion layer / base (that is, the temporary fixing material is composed of the photothermal conversion layer), the adhesive layer is present. At this time, it is possible to further prevent the substrate from being damaged by infrared rays.

  The photothermal conversion layer is a layer in which infrared rays are absorbed by its constituent components and converted into thermal energy, and the constituent resin of the photothermal conversion layer undergoes thermal decomposition or the like due to the thermal energy, resulting in a decrease in adhesive strength. An adhesive bond layer is a layer used in order to temporarily fix a base material on a support body through a photothermal conversion layer.

  Hereinafter, the temporary fixing composition, which is a raw material composition of the temporary fixing material used in the substrate processing method of the present invention, particularly the composition used for forming the photothermal conversion layer and the adhesive layer, will be described. Each step of the base material processing method using the fixing material and the semiconductor device obtained by the base material processing method will be described.

[Temporary fixing composition]
Examples of the temporary fixing composition that can be used for forming the temporary fixing material include a composition (I) containing a thermoplastic resin and a composition (II) containing a thermosetting resin. Hereinafter, after describing the composition (I), the composition (II) will be described.

[Composition (I) containing thermoplastic resin]
The composition (I) of the present invention contains a thermoplastic resin. The composition (I) used for forming the above-mentioned photothermal conversion layer further contains an infrared absorber. The composition (I) used for forming the above-mentioned adhesive layer usually does not contain an infrared absorber.

<Thermoplastic resin>
Examples of the thermoplastic resin include cycloolefin polymers, petroleum resins, terpene resins, novolac resins, and mixtures thereof. From the viewpoint of heat resistance, the composition (I) preferably contains at least a cycloolefin polymer. In addition, the composition (I) preferably contains a thermoplastic resin other than the cycloolefin polymer for the purpose of controlling the temperature at which the substrate and the support are bonded together via the temporary fixing material.

《Cycloolefin polymer》
Examples of the cycloolefin polymer include an addition copolymer of a cyclic olefin and an acyclic olefin, a ring-opening metathesis polymer of one or more cyclic olefins, and a hydrogenation of the ring-opening metathesis polymer. A polymer is mentioned. Methods for synthesizing such cycloolefin polymers are conventionally known.

Examples of the cyclic olefin include norbornene olefin, tetracyclododecene olefin, dicyclopentadiene olefin, and derivatives thereof. Examples of the derivative include an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms) and an alkylidene group (preferably 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms). Alkylidene group), an aralkyl group (preferably an aralkyl group having 7 to 30 carbon atoms, more preferably an aralkyl group having 7 to 18 carbon atoms), a cycloalkyl group (preferably having 3 to 30 carbon atoms, more preferably 3 to 18 carbon atoms). A cycloalkyl group), a hydroxy group, an alkoxy group (preferably an alkoxy group having 1 to 10 carbon atoms), an acetyl group, a cyano group, an amide group, an imide group, a silyl group, an aromatic ring, an ether bond, and an ester bond. Derivatives.
A preferred example of the cyclic olefin is a compound represented by the formula (1).

式（１）中のＲ¹〜Ｒ³は以下のとおりである：Ｒ¹およびＲ²はそれぞれ独立に水素またはアルキル基（好ましくは炭素数１〜２０、より好ましくは炭素数１〜１０のアルキル基）である。Ｒ³はそれぞれ独立に水素、アルキル基（好ましくは炭素数１〜２０、より好ましくは炭素数１〜１０のアルキル基）、シクロアルキル基（好ましくは炭素数３〜３０、より好ましくは炭素数３〜１８のシクロアルキル基）、アリール基（好ましくは炭素数６〜１８のアリール基）、アラルキル基（好ましくは炭素数７〜３０、より好ましくは炭素数７〜１８のアラルキル基）、アルコキシ基（好ましくは炭素数１〜１０のアルコキシ基）、アルコキシカルボニル基（好ましくは炭素数１〜１１のアルコキシカルボニル基）、アルデヒド基、アセチル基、ニトリル基である。また、２つのＲ³が相互に結合して環構造（例：脂環）を形成してもよく、例えば当該脂環がＲ³として例示した前記基を置換基として有してもよい。

R ^{1 to} R ³ in the formula (1) are as follows: R ¹ and R ² are each independently hydrogen or an alkyl group (preferably having 1 to 20 carbon atoms, more preferably alkyl having 1 to 10 carbon atoms). Group). R ³ is independently hydrogen, an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms), or a cycloalkyl group (preferably having 3 to 30 carbon atoms, more preferably 3 carbon atoms). -18 cycloalkyl group), an aryl group (preferably an aryl group having 6 to 18 carbon atoms), an aralkyl group (preferably an aralkyl group having 7 to 30 carbon atoms, more preferably an aralkyl group having 7 to 18 carbon atoms), an alkoxy group ( Preferably they are a C1-C10 alkoxy group), an alkoxycarbonyl group (preferably C1-C11 alkoxycarbonyl group), an aldehyde group, an acetyl group, and a nitrile group. Moreover, two R < ³ > may couple | bond together and may form a ring structure (example: alicyclic ring), for example, the said alicyclic ring may have the said group illustrated as R < ³ > as a substituent.

  Examples of the acyclic olefin include linear or branched olefins having 2 to 20 carbon atoms, preferably 2 to 10 carbon atoms, more preferably ethylene, propylene and butene, and particularly preferably ethylene. .

The addition copolymer of cyclic olefin and acyclic olefin includes, for example, a structural unit represented by the formula (I) and a structural unit derived from an acyclic olefin (polymerizable double bond of acyclic olefin). A structural unit based on the above reaction).

式（Ｉ）中のＲ¹〜Ｒ³は式（１）中のＲ¹〜Ｒ³とそれぞれ同義である。

R ¹ in formula (I) to R ³ are the same meanings as R ¹ to R ³ in the formula (1).

  Examples of commercially available addition copolymers include “TOPAS” manufactured by TOPAS ADVANCED POLYMERS, and “APEL” manufactured by Mitsui Chemicals, Inc.

The ring-opening metathesis polymer and its hydrogenated ring-opening metathesis polymer of one or more cyclic olefins are, for example, polymers having a structural unit represented by the formula (II), and the ring-opening metathesis The polymer obtained by hydrogenating the polymer is, for example, a polymer having a structural unit represented by the formula (III).

式（II）および（III）中のＲ¹〜Ｒ³は式（１）中のＲ¹〜Ｒ³とそれぞれ同義である。

R ¹ to R in the formula (II) and (III) ³ are respectively synonymous with R ¹ to R ³ in the formula (1).

  Examples of commercially available ring-opening metathesis polymers include “ZEONOR”, “ZEONEX” manufactured by Nippon Zeon Co., Ltd., and “ARTON” manufactured by JSR Corporation.

  The weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) of the cycloolefin polymer is usually 10,000 to 100,000, preferably 30,000 to 100,000 in terms of polystyrene. . When the number average molecular weight measured by the gel permeation chromatography (GPC) method of the cycloolefin polymer is Mn, the molecular weight distribution represented by Mw / Mn is usually 2.0 to 4.0, preferably 3. 0 to 4.0.

  The content of the cycloolefin polymer is preferably 30 to 90% by mass, more preferably 50 to 75% by mass, when the total solid content of the composition (I) excluding the solvent is 100% by mass. When there is a work process in a high temperature environment (example: 225 to 300 ° C.) in the processing of the base material, in order to prevent damage to the base material itself and each member (eg bump) formed on the base material, High heat resistance may be required for the temporary fixing material that also serves to protect the base material. When the composition (I) contains a cycloolefin polymer having excellent heat resistance, the temporary fixing material formed therefrom also has high heat resistance.

<< Thermoplastic resin other than cycloolefin polymer >>
Examples of the thermoplastic resin other than the cycloolefin polymer include petroleum resins, terpene resins, novolac resins, and mixtures thereof. Among these, a terpene resin is preferable from the viewpoint of compatibility with the cycloolefin polymer.

  In the composition (I), when a thermoplastic resin other than the cycloolefin polymer is used, the thermoplastic resin (mass ratio) other than the cycloolefin polymer / cycloolefin polymer is 50/50 to 99/1. Is more preferable, more preferably 60/40 to 90/10, and particularly preferably 65/35 to 85/15. When the content of the thermoplastic resin is within the above range, it is preferable from the viewpoints of heat resistance, peelability and adhesiveness.

The petroleum resin petroleum resin, for example, C5 petroleum resin, C9 petroleum resin, C5-based / C9-based mixed petroleum resin, a polymer of vinyl-substituted aromatic compound, a copolymer of olefin and vinyl-substituted aromatic compound, Examples include a copolymer of a cyclopentadiene compound and a vinyl-substituted aromatic compound, a hydrogenated product thereof, and a mixture thereof. Of these, C5 petroleum resins, C9 petroleum resins, C5 / C9 mixed petroleum resins, polymers of vinyl-substituted aromatic compounds, hydrogenated products thereof, and mixtures thereof are preferable. As the C5 petroleum resin, an aliphatic resin is preferable, and as the C9 petroleum resin, an alicyclic resin is preferable. Among these, C9 petroleum resin and its hydrogenated product are particularly preferable.

  The weight average molecular weight (Mw) measured by GPC method of petroleum resin is 20,000 or less normally in polystyrene conversion, Preferably it is 100-20,000, More preferably, it is 200-10,000, Most preferably, it is 300-5. , 000.

The terpene resins terpene resins, for example, terpene polymers, pinene polymer, aromatic modified terpene polymers, hydrogenated terpene resins and terpene-phenol copolymer.

The novolak resin can be obtained by, for example, condensing phenols and aldehydes in the presence of a catalyst (eg, oxalic acid).

  Examples of phenols include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-butylphenol, m-butylphenol, p-butylphenol, 2, 3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, 2,3,5-trimethylphenol, 3,4,5-trimethyl Examples include phenol, catechol, resorcinol, pyrogallol, α-naphthol, and β-naphthol.

Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, and benzaldehyde.
Preferable specific examples of the novolak resin include a phenol / formaldehyde condensed novolak resin, a cresol / formaldehyde condensed novolak resin, and a phenol-naphthol / formaldehyde condensed novolak resin.

  The weight average molecular weight (Mw) measured by GPC of the novolak resin is usually 2,000 or more, preferably 2,000 to 20,000 in terms of polystyrene. When the number average molecular weight measured by the GPC method of the novolak resin is Mn, the molecular weight distribution represented by Mw / Mn is usually 1.0 to 10, preferably 1.5 to 5.0.

<Rubber component>
The composition (I) may contain a rubber component in order to improve adhesiveness and mechanical properties.
Examples of rubber components include natural rubber, isoprene rubber, styrene butadiene rubber, polybutadiene rubber, butyl rubber, halogenated butyl rubber, ethylene propylene diene rubber, acrylonitrile butadiene rubber, chloroprene rubber, acrylic rubber, hydrin rubber, polysulfide rubber, silicone rubber, fluorine Rubber.

  In the composition (I), when a rubber component is used, the content of the rubber component is usually 0.1 to 40 parts by weight, preferably 1 to 35 parts by weight, particularly preferably 100 parts by weight of the thermoplastic resin. 5 to 30 parts by mass. When the content of the rubber component is in the above range, it is preferable from the viewpoints of heat resistance and adhesiveness.

<Infrared absorber>
Examples of the infrared absorber include carbon black, graphite powder; fine metal powder such as iron, aluminum, copper, nickel, cobalt, manganese, chromium, zinc, tellurium; metal oxide powder such as black titanium oxide; phthalocyanine compound And metal complex compounds that act as pigments that absorb near infrared rays, such as naphthalocyanine compounds and dithiol metal complex compounds. Among these, carbon black is particularly preferable from the viewpoint of reducing the peeling force by infrared irradiation.

  When carbon black is used as the infrared absorber, it is preferable to use carbon black having a particle size of 5 to 500 nm, more preferably 50 to 300 nm, and more preferably 100 to 250 nm. When the particle size of the carbon black is within the above range, it is preferable from the viewpoint of dispersibility in the temporary fixing composition. The particle size of carbon black is measured by a light scattering method.

  In composition (I) used for formation of a photothermal conversion layer, content of an infrared absorber is 0.1-50 mass% normally, Preferably it is 1-40 mass%, More preferably, it is 5-25 mass%. . When the content of the infrared absorbent is equal to or more than the lower limit value, heat generation of the photothermal conversion layer due to infrared irradiation becomes sufficient, and the substrate can be peeled well. When the content of the infrared absorber is not more than the above upper limit value, the film-forming property of the photothermal conversion layer is excellent, and poor adhesion with other layers hardly occurs.

  In the composition (I) used for forming the adhesive layer, the content of the infrared absorber is usually less than 5% by mass, preferably 3% by mass or less, and more preferably contains no infrared absorber.

<Antioxidant>
The composition (I) may contain an antioxidant.
Examples of the antioxidant include 2,6-di-t-butyl-4-methylphenol, 2,2′-dioxy-3,3′-di-t-butyl-5,5′-dimethyldiphenylmethane, tetrakis [Methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate It is done.

  In the composition (I), when an antioxidant is used, the content of the antioxidant is appropriately selected according to desired properties, but is preferably 0.1 to 100 parts by mass of the thermoplastic resin. It is 10 mass parts, More preferably, it is 0.5-5 mass parts.

<solvent>
In preparing the composition (I), it is preferable to use a solvent in that the viscosity of the composition (I) is set in a range suitable for coating. Examples of the solvent include hydrocarbons such as limonene, mesitylene, dipentene, pinene, bicyclohexyl, cyclododecene, 1-tert-butyl-3,5-dimethylbenzene, butylcyclohexane, cyclooctane, cycloheptane, cyclohexane, and methylcyclohexane. Alcohols / ethers such as anisole, propylene glycol monomethyl ether, dipropylene glycol methyl ether, diethylene glycol monoethyl ether, diglyme; ethylene carbonate, ethyl acetate, N-butyl acetate, ethyl lactate, ethyl 3-ethoxypropionate, propylene glycol Esters / lactones such as monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene carbonate, γ-butyrolactone; cyclo Ketones such as ntanone, cyclohexanone, methyl isobutyl ketone, 2-heptanone; amides / lactams such as N-methyl-2-pyrrolidinone, etc., which may be used alone or in combination of two or more. May be. Among these, hydrocarbons are preferable from the viewpoint of the solubility of thermoplastic resins, particularly cycloolefin polymers.

  By using a solvent, it becomes easy to adjust the viscosity of the composition (I), and therefore it is easy to form a temporary fixing material layer (eg, photothermal conversion layer, adhesive layer) on the substrate or the support. It becomes. For example, the solvent can be used in such a range that the solid content concentration of the composition (I) is usually 10 to 50% by mass, preferably 25 to 50% by mass. Here, the solid content concentration is a total concentration of all components other than the solvent.

[Composition (II) containing thermosetting resin]
The composition (II) of the present invention contains a thermosetting resin. The composition (II) used for forming the above-mentioned photothermal conversion layer further contains an infrared absorber. The composition (II) used for forming the above-mentioned adhesive layer usually does not contain an infrared absorber.

  Examples of the thermosetting resin include an epoxy resin, a phenol resin, an unsaturated polyester resin, a diallyl phthalate resin, a liptadiene liquid resin, a urethane liquid resin, and a silicone liquid resin. These may be used alone or in combination of two or more.

  Examples of the epoxy resin include bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, and bisphenol A novolak. Type epoxy resin, bisphenol F novolak type epoxy resin, cresol novolak type epoxy resin, alicyclic epoxy resin, glycidyl ester type epoxy resin, glycidyl ether type epoxy resin, glycidyl amine type epoxy resin, urethane modified epoxy resin, rubber modified epoxy resin , Epoxidized (meth) acrylic oligomer, and epoxidized (meth) acrylic polymer.

  Examples of curing agents that can be used with epoxy resins include amide curing agents such as dicyandiamide and polyamide; amine curing agents such as ammonia, triethylamine, and diethylamine; phenol novolac resins, cresol novolac resins, and p-xylene-novolak resins. And phenolic curing agents such as acid anhydrides.

  In order to improve the curability of the composition (II), a radical polymerizable compound may be used. Examples of the radical polymerizable compound include polyfunctional (meth) acrylates, polyfunctional urethane (meth) acrylates, and (meth) acryloyl group-containing isocyanurates.

  In order to improve the adhesive strength and moisture resistance reliability of the composition (II), a silane coupling agent may be used. Examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 2- (3,4-epoxycyclohexyl) ethyl. Trimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyltrimethoxysilane, 3 -Aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane, N- (2- (vinylbenzylamino) ethyl) 3-aminopropyltrimethoxysilane hydrochloride, 3-methacryloxypropyltrimethoxysilane , - chloropropyl methyl dimethoxy silane, and 3-chloropropyl trimethoxysilane.

  In order to adjust the fluidity of the composition (II), a thickener may be used. Examples of the thickener include acrylic rubber, shrimp chlorohydrin rubber, isoprene rubber, and butyl rubber.

  In order to adjust the viscosity of the composition (II), a solvent may be used. Examples of the solvent include amides such as N, N-dimethylformamide; esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate and 3-methoxybutyl acetate; ethylene glycol monomethyl ether, propylene glycol monomethyl ether, Examples include ethers such as diethylene glycol monobutyl ether and diethylene glycol ethyl methyl ether; ketones such as acetone and methyl ethyl ketone; alcohols such as methanol and ethanol; aromatic hydrocarbons such as benzene and toluene. These are used alone. Or two or more of them may be used in combination. For example, the solvent can be used in the range where the solid content concentration of the composition (II) is usually 5 to 50% by mass, preferably 10 to 40% by mass. Here, the solid content concentration is a total concentration of all components other than the solvent.

In addition to the above components, the composition (II) may contain various additives such as an antioxidant, a leveling agent, a polymerization inhibitor, and an ultraviolet absorber depending on the required properties and performance.
The composition (II) used for forming the photothermal conversion layer contains the above-described infrared absorber (the same applies to the preferred examples). Content of an infrared absorber is 0.01-50 mass% normally, Preferably it is 0.1-40 mass%, More preferably, it is 0.5-25 mass%.
In the composition (II) used for forming the adhesive layer, the content of the infrared absorber is usually less than 5% by mass, preferably 3% by mass or less, more preferably free of the infrared absorber.

<Preparation of temporary fixing composition>
For the preparation of the temporary fixing composition of the present invention, for example, a twin screw extruder, a single screw extruder, a continuous kneader, a roll kneader, a pressure kneader, or a Banbury mixer can be used. In addition, for the purpose of removing impurities, filtration can be appropriately performed.

<Characteristics of temporary fixing material formed from temporary fixing composition>
By performing infrared irradiation treatment on the photothermal conversion layer in the temporary fixing material, infrared rays are absorbed by the infrared absorbent in the photothermal conversion layer and converted into thermal energy. The generated thermal energy raises the temperature of the photothermal conversion layer, and eventually the temperature reaches the thermal decomposition temperature of the resin in the photothermal conversion layer, the resin is thermally decomposed, and the gas generated by the thermal decomposition is a void in the photothermal conversion layer. It is considered that a layer (void) is formed, and as a result, the support and the substrate can be easily separated.

  The temporary fixing material can temporarily fix the base material at a temperature of, for example, 300 ° C. or less, and can hold (or protect) the base material during processing of the base material even in a high temperature environment (eg, 225 to 300 ° C.). You can maintain power. The holding force is evaluated by, for example, a shearing adhesive force or an adhesive force in a direction perpendicular to the surface of the support. Thus, the temporary fixing material of the present invention has a sufficient holding force against the shearing force applied during the processing of the substrate and the force applied in the direction perpendicular to the surface of the support. The temporary fixing material of the present invention is a thin film of a base material used near 25 ° C., photofabrication (eg, etching processing used in a temperature range of about 25 to 300 ° C., formation of a sputtered film, 225 to 300 ° C. The substrate can be held on the support also in the plating process and the plating reflow process used in a temperature range of about.

  Since the temporary fixing material formed from the temporary fixing composition of the present invention has such characteristics, various processing treatments required in the scene of modern economic activities (eg, miniaturization processing of various material surfaces). In processing and various surface mounting), it is suitably used as a temporary fixing material for a substrate.

[Substrate treatment method]
The substrate processing method of the present invention includes (1) a step of temporarily fixing a substrate and a support made of a silicon wafer via a temporary fixing material having a photothermal conversion layer, and (2) processing the substrate. (3) irradiating the temporary fixing material with infrared rays from the side of the support without focusing on the surface opposite to the contact surface of the support with respect to the temporary fixing material, and (4) A step of peeling the substrate from the support.

<< Process (1) >>
In the step (1), for example, (1-1) a temporary fixing material layer is formed on the surface of a support made of a silicon wafer and / or a surface-treated substrate as necessary, and one or more temporary layers are temporarily formed. By pasting a base material and a support through a temporary fixing material consisting of a fixing material layer, or (1-2) a temporary fixing material consisting of one or more temporary fixing material layers on the surface of the support The base material can be temporarily fixed on the support by forming the base material on the temporary fixing material. The laminate thus formed has a configuration of support / temporary fixing material (temporary fixing material layer) / base material, and preferably has a configuration of support / photothermal conversion layer / adhesive layer / base material.

  As a method for forming the temporary fixing material layer (eg, photothermal conversion layer, adhesive layer), for example, (i) using the above-described temporary fixing composition, the temporary fixing material layer may be formed on the support and / or the substrate. (Ii) Using the above-described temporary fixing composition, a temporary fixing material layer is formed on a PET (Polyethylene Terephthalate) film that has been subjected to a release treatment with a constant film thickness. Thereafter, a method of transferring to a support and / or a substrate by a laminating method may be mentioned. From the viewpoint of film thickness uniformity, the method (i) is preferred.

  Examples of the method for applying the temporary fixing composition include a spin coating method and an ink jet method. In the spin coating method, for example, temporarily fixed under the conditions that the rotation speed is 300 to 3,500 rpm (preferably 500 to 1,500 rpm), the acceleration is 500 to 15,000 rpm / second, and the rotation time is 30 to 300 seconds. And a method of spin coating the composition for use.

  After the temporary fixing composition is applied and the coating film is formed, for example, by baking with a hot plate or the like and evaporating the solvent, the temporary fixing material layer (eg, photothermal conversion layer, adhesive layer) is formed. Can be formed. As for the baking conditions, for example, the temperature is usually 150 to 275 ° C., preferably 150 to 260 ° C., and the time is usually 2 to 20 minutes, more preferably 3 to 15 minutes.

  In the photothermal conversion layer, the content of the infrared absorber is usually 5 to 60% by mass, preferably 10 to 50% by mass, and more preferably 20 to 40% by mass with respect to 100% by mass of the total photothermal conversion layer. When the content of the infrared absorber is within the above range, it is preferable from the viewpoint of the peelability of the substrate.

  The thickness of the photothermal conversion layer is usually 0.1 to 20 μm, preferably 0.5 to 10 μm, more preferably 1 to 10 μm. When the thickness of the light-to-heat conversion layer is in the above range, the light-to-heat conversion layer absorbs the irradiated infrared rays satisfactorily, so that the substrate can be peeled off from the support well, and the light-to-heat conversion layer and other layers Excellent adhesion.

  The thickness of an adhesive bond layer is 10-200 micrometers normally, Preferably it is 10-100 micrometers, More preferably, it is 10-50 micrometers. When the thickness of the adhesive layer is within the above range, the surface irregularities of the substrate can be followed, the holding power is sufficient, and the adhesiveness between the adhesive layer and other layers is excellent.

  In the method (i), as a method of bonding the base material and the support, for example, a method of forming a temporarily fixing material layer on one or both of the base material and the support and bonding the both together Can be mentioned. When forming a temporary fixing material comprising a photothermal conversion layer and an adhesive layer, for example, a photothermal conversion layer comprising a temporary fixing composition containing an infrared absorbent is formed on a support, and an infrared absorbent is formed on a substrate. There is a method in which an adhesive layer composed of a temporary fixing composition that does not substantially contain is formed, and the support and the substrate are bonded so that the photothermal conversion layer and the adhesive layer are in contact with each other.

  The temperature at this time is appropriately selected according to the components contained in each temporary fixing composition, the coating method, and the like. In this way, the substrate is firmly held on the support via the temporarily fixing material layer. The crimping condition may be performed, for example, by applying a pressure of 0.05 to 3 MPa at 150 to 300 ° C. for 1 to 5 minutes.

  Examples of the base material to be processed include a semiconductor wafer, a semiconductor chip, a glass substrate, a resin substrate, a metal substrate, a metal foil, a polishing pad, and a resin coating film. Bumps, wirings, insulating films, etc. are usually formed on semiconductor wafers and chips. Examples of the resin coating include a layer containing an organic component as a main component; specifically, a photosensitive resin layer formed from a photosensitive material, an insulating resin layer formed from an insulating material, Examples thereof include a photosensitive insulating resin layer formed from a photosensitive insulating resin material.

  A silicon wafer is used as the support. In the prior art, a transparent substrate such as a glass substrate or a quartz substrate is preferably used as the support, but these are low in versatility and are considered disadvantageous in terms of yield. For example, Pyrex (trade name) is very expensive compared to silicon wafers, and large-diameter ones are generally not available and are difficult to obtain. In the present invention, a silicon wafer is used as the support, and the silicon wafer is excellent in productivity because it is versatile and inexpensive. The thickness of the silicon wafer as the support is usually 700 to 800 μm, preferably 725 to 775 μm.

  The substrate processing method of the present invention can be applied to a semiconductor wafer having bumps, particularly a semiconductor wafer having pillar bumps having poor heat resistance (eg, pillar bumps composed of a copper portion and a solder portion). it can.

  When the temporary fixing material layer is formed on the base material, the surface of the base material can be pretreated in order to make the temporary fixing material spread in the plane. Examples of the surface treatment method include a method of applying a surface treatment agent to the surface of the substrate in advance.

  Examples of the surface treatment agent include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl)- 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl Trimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7- Riazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl- 3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene ) -3-Aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, and hexamethyldisilazane.

<< Step (2) >>
Step (2) is a step of processing the base material temporarily fixed on the support as described above. Examples of the processing of the substrate include photofabrication including one or more processing selected from thinning of the substrate (eg, back surface grinding); etching processing, formation of a sputtered film, plating processing, and plating reflow processing. Can be mentioned.

  In photofabrication, the substrate may be exposed to a high temperature environment. For example, in so-called three-dimensional mounting in which a plurality of chips are stacked and mounted in a package, the wafer or chip is temporarily fixed to a support, for example, processing of the wafer or chip (eg, through-hole formation, bump formation, rewiring) Wafer thinning) and stacking of chips (eg, melt-flowing plating to electrically connect chips). Therefore, it is desired that the temporarily fixing material has resistance (heat resistance) to a plating reflow process or the like. For example, by using the composition (I) containing a cycloolefin polymer as a temporary fixing composition, a temporary fixing material excellent in heat resistance capable of protecting the substrate without being substantially melted even in a high temperature environment is formed. Therefore, for example, breakage of a semiconductor chip or breakage of a bump can be prevented during processing of the base material.

  The processing of the substrate is not particularly limited as long as it is performed at a temperature at which the holding force of the temporarily fixed material is not lost. In the present invention, the temporary fixing material layer has a holding force capable of holding (or protecting) the base material during processing even in a low temperature and high temperature environment.

  Hereinafter, as a base material processing process, a processing process performed at the time of three-dimensional mounting will be described as an example. In the three-dimensional mounting, a through electrode extending in a direction perpendicular to the surface of the substrate is formed, and a connection electrode such as a pad electrode or a bump is formed on an end portion or wiring of the through electrode. By connecting the connection electrodes formed in this way, the stacked base materials are connected to each other.

  (I) A resist is applied on the base material temporarily fixed on the support through the temporary fixing material in the step (1), and exposure processing and development processing are performed to form a resist layer patterned in a predetermined shape. To do. For example, a plurality of circular resist patterns may be formed on the substrate.

(Ii) Using the resist layer as a mask, the portion of the base material patterned into a predetermined shape is etched to form an opening (hole). Thereafter, the resist layer is stripped by a stripping solution or ashing (eg, O ₂ ashing). For etching, dry etching or wet etching can be used.

(Iii) An insulating layer made of SiO ₂ or the like is formed on the surface of the substrate where the opening is formed.
(Iv) A barrier layer made of TiW, TiN, or the like is formed by sputtering for the purpose of preventing the conductor from diffusing into the insulating layer. Next, a seed layer made of copper or the like is formed by sputtering.

  (V) A resist is applied on the surface of the base material where the opening is formed, and an exposure process and a development process are performed to form a resist layer that is patterned into a shape corresponding to the opening of the base material. Next, a plating process (Sn / Cu plating or the like) is performed to fill the opening in the base material with a conductor to form a through electrode. Thereafter, the resist layer is removed, and the barrier layer and the seed layer are removed by dry etching.

  (Vi) A connection electrode such as a pad electrode or a bump is formed on the through electrode of the base material processed in this manner by reflow. Next, the laminated base materials can be connected by connecting the formed connection electrodes.

<< Step (3) and Step (4) >>
After processing the base material, the temporary fixing material is irradiated with infrared rays from the support side.
Irradiate the surface of the support opposite to the surface of the support opposite to the temporary fixing material without focusing, thereby suppressing the rise in the temperature of the silicon wafer, which is the support, and thus the decrease in the infrared transmittance Can do. In particular, peeling can be efficiently performed by irradiating an infrared laser focused on the photothermal conversion layer of the temporary fixing material.

  If it is after the infrared irradiation with respect to a temporarily fixed material, a base material can be easily peeled from a support body, without specifically requiring the heat processing of a temporarily fixed material. In this invention, since it is not necessary to perform the further heat processing after infrared irradiation at the time of peeling, even if it is a base material which has a pillar bump inferior in heat resistance, the damage can be prevented.

  Examples of the light source for irradiation light include infrared lasers such as Nd: YAG laser, carbon dioxide laser, and semiconductor laser; infrared lamps such as flash lamps. Among these, infrared lasers are preferable. For example, infrared rays having a wavelength of 1 to 1.8 μm can be irradiated.

  Irradiation with an infrared laser can be carried out using an irradiation method or apparatus generally used in industry, and is not particularly limited. As a laser beam scanning method, an object to be irradiated consisting of a support / temporary fixing material / substrate is fixed and irradiated by scanning the laser beam, or the laser beam is fixed and the object to be irradiated is moved and irradiated. In this way, the entire irradiated body (particularly the photothermal conversion layer) may be irradiated with a laser beam. The scanning speed and the moving speed of the irradiated object here are, for example, 1 to 5,000 mm / second, preferably 10 to 1,000 mm / second. On the irradiation surface of the irradiated object, for example, the scanning of the laser beam or the movement of the irradiated object is performed so that the laser beam is irradiated in a zigzag manner or the laser beam is irradiated in a spiral shape from the end toward the center. Just do it.

  By scanning with a laser beam and / or moving the irradiated object, the temperature rise of the silicon wafer as a support can be suppressed, and exposure can be performed without lowering the light transmittance. Can do.

Irradiation conditions vary depending on the type of light source and the like. For example, the shearing force of 0.01 to 10 N / cm ² or the application of a force of 1 to 100 N / cm ^{2 in} the direction perpendicular to the surface of the support is applied from the support. Infrared irradiation treatment conditions (irradiation amount, scanning / moving speed, etc.) may be set so that the substrate can be peeled off. Specifically, the usable laser power is preferably 0.1 to 100 W, more preferably 5 to 25 W.

As the peeling treatment after the infrared irradiation, for example, a shearing treatment (shearing force: usually 0.01 to 10 N / cm) such as shifting the support and the base material in a substantially horizontal direction on the temporarily fixing surface (the surface of the support). ² , preferably 0.01 to 1 N / cm ² ), a method of peeling the substrate from the support; a method of peeling the substrate in a direction perpendicular to the surface of the support (perpendicular to the surface of the support) Force in the direction: usually 1 to 100 N / cm ² , preferably 5 to 50 N / cm ² ).

  More specifically, the substrate is slid in the horizontal direction with respect to the surface of the support, and at the same time, the support is fixed, or a force that antagonizes the force applied to the substrate is applied to the support. The method of peeling a base material from a support body by is mentioned. In the present invention, “shearing” refers to applying a force in a direction substantially parallel to the temporary fixing surface between the support and the substrate.

  In addition, after peeling a base material from a support body, the adhesive bond layer, the composition for temporary fixing resulting from it, etc. may remain. The adhesive layer remaining on the substrate after peeling can be easily peeled off by peeling treatment. Moreover, the composition for temporary fixing remaining on the base material after peeling can be removed by washing with a solvent (cleaning liquid) that can be used when preparing the above-described composition for temporary fixing.

  For the peeling of the adhesive layer, it is preferable to use a pressure-sensitive adhesive tape that can form an adhesive force between the adhesive layer and the base material and the adhesive layer. The adhesive layer can be peeled by adhering the pressure-sensitive adhesive tape on the adhesive layer and then peeling it.

  Examples of the cleaning method include a method of immersing the substrate in the cleaning solution, a method of spraying the cleaning solution on the substrate, and a method of applying ultrasonic waves while immersing the substrate in the cleaning solution. The temperature of the cleaning liquid is not particularly limited, but is preferably 20 to 80 ° C, more preferably 20 to 50 ° C.

[Semiconductor device]
The semiconductor device of the present invention is obtained by processing a base material by the base material processing method of the present invention. Since the above-described temporary fixing material is easily removed when the semiconductor device such as a semiconductor element is peeled off, the semiconductor device such as the semiconductor element is extremely reduced in contamination (for example, spots and scorching) due to the temporary fixing material. ing. In the semiconductor device of the present invention, damage and wear of the base material itself and each member of the base material are extremely reduced.

Hereinafter, one embodiment of the present invention will be described in detail with reference to examples.
Unless otherwise specified, “part” represents “part by mass”.
The weight average molecular weight (Mw) and number average molecular weight (Mn) of the polymer can be measured using, for example, GPC columns (2 G2000HXL, 1 G3000HXL, 1 G4000HXL) manufactured by Tosoh Corporation. .

1. Preparation of Composition for Temporary Fixation [Preparation Example 1] Preparation of Blacking Agent Dispersion 1 20 parts of carbon black (particle size by light scattering method: 10 to 200 nm), 5 parts of modified acrylic block copolymer (Big Chemie Japan Co., Ltd., trade name “DISPERBYK-2001”) and 75 parts of 3-methoxybutyl acetate were mixed by a bead mill to prepare a black agent dispersion 1.

Synthesis Example 1 Preparation of Polymer Solution 1 In a flask, 6 parts 2,2′-azobis (2,4-dimethylvaleronitrile), 200 parts diethylene glycol ethyl methyl ether, 14 parts methacrylic acid, 26 parts Styrene, 29 parts of glycidyl methacrylate, 31 parts of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate and 3 parts of α-methylstyrene dimer were charged and gently purged. Stirring started. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 5 hours to obtain a polymer solution 1 containing 35% by mass of a polymer. The weight average molecular weight in terms of polystyrene determined by gel permeation column chromatography of the polymer was 13,000.

Example 1 Preparation of Temporary Fixing Composition 1 80 parts of cycloolefin polymer (trade name “ARTON RX4500”, manufactured by JSR Corporation) and 20 parts of terpene-based hydrogenated resin (trade name “CLEARON P150”) “Yasuhara Chemical Co., Ltd.”, 20 parts of liquid styrene butadiene rubber (trade name “L-SBR-820”, Kuraray Co., Ltd.) and 3 parts of hindered phenol antioxidant (trade name “ IRGANOX 1010 "(manufactured by BASF), 125 parts of carbon black dispersion (trade name" MHI Black # 209 ", Gokoku Dye Co., Ltd., solid content 35% by mass) and 367 parts of mesitylene Thus, a temporary fixing composition 1 was prepared.

[Examples 2 and 4] Preparation of Temporary Fixing Composition 2 and Temporary Fixing Composition 4 In Example 1, except that the ingredients were changed as shown in Table 1, Temporary fixing composition 2 and temporary fixing composition 4 were prepared.

[Example 3] Preparation of temporary fixing composition 3 36 parts of blackener dispersion 1 prepared in Preparation Example 1, 100 parts of polymer solution 1 prepared in Synthesis Example 1, and 45 parts of acryloyl oligomer ( Trade name “Aronix M-520” manufactured by Toa Gosei Co., Ltd.), 15 parts of bisphenol A novolac type epoxy resin (trade name “Epicoat 157S65”, manufactured by Japan Epoxy Resins Co., Ltd.), and 20 parts of 3- Glycidoxypropyltrimethoxysilane, 0.25 part of a polyether-modified silicone solution (trade name “DOW CORNING TORAY 8019 ADDITIVE” manufactured by Toray Dow Corning Co., Ltd.), 0.05 part of aluminum N-nitroso Mix phenylhydroxyamine with 680 parts propylene glycol monomethyl ether acetate. And it was thus adjusted temporary fixing composition 3.

2. Evaluation [Example 5]
The temporary fixing composition 4 is applied onto the silicon wafer 1 (base material) by a spin coating method, heated using a hot plate at 160 ° C. for 5 minutes in the air, and then at 230 ° C. under a nitrogen atmosphere. The substrate was heated for 10 minutes to obtain a substrate having the silicon wafer 1 and a coating film (adhesive layer) having a thickness of 40 μm. The obtained substrate was cut into a length of 1 cm and a width of 1 cm to obtain a substrate 1 having an adhesive layer.

  The temporary fixing composition 1 was applied onto a silicon wafer 2 (thickness: 750 μm, support) by spin coating, heated at 160 ° C. for 5 minutes in the air using a hot plate, and then in a nitrogen atmosphere The substrate having the silicon wafer 2 and the coating film (photothermal conversion layer) having a thickness of 3 μm was obtained by heating at 230 ° C. for 10 minutes. The obtained substrate was cut into a length of 1 cm and a width of 1 cm to obtain a substrate 2 having a photothermal conversion layer.

  The above-mentioned substrate 1 and substrate 2 are bonded so that the adhesive layer and the photothermal conversion layer are in contact with each other, and a force of 15 N is applied for 120 seconds at 230 ° C. using a die bonder device to bond silicon wafer 1 and silicon wafer 2 together. A test laminate was obtained, which was laminated via a temporary fixing material composed of an agent layer and a photothermal conversion layer. That is, the test laminate has a layer structure of silicon wafer 1 (base material) / adhesive layer / photothermal conversion layer / silicon wafer 2 (support).

After heating the test laminate for 3 hours at 200 ° C. using an open, using a peel tester, force in the direction perpendicular to the silicon wafer 1 (at a speed of 200 μm / second, 20 N / cm ² at 23 ° C.). However, it was confirmed that the silicon wafer 1 and the silicon wafer 2 were fixed without being displaced.

  Next, the test laminate was focused on the photothermal conversion layer with an all-solid-state continuous wave infrared laser device (trade name “MARTIX 1064CW”, manufactured by Coherent Japan Co., Ltd.), and the infrared laser from the silicon wafer 2 side. (The wavelength is 1064 nm) was applied to the test laminate. Irradiation was performed by scanning in a zigzag manner (250 reciprocations) (scanning speed was 100 mm / sec).

A force (200 N / cm ² at 25 ° C. at a speed of 200 μm / ^second ) was applied to the test laminate after irradiation in a direction perpendicular to the silicon wafer 1 using a peel tester. It was evaluated whether or not. The evaluation results are shown in Table 2.

[Examples 6 to 9, Comparative Examples 1 and 2]
In Example 5, the adhesive layer and the photothermal conversion layer were formed using the temporary fixing compositions shown in Table 2, respectively, and irradiation was performed at the focal position and the scanning speed shown in Table 2. Evaluation was performed in the same manner as in Example 5 except that the force shown in Table 2 was applied. The evaluation results are shown in Table 2.

Claims (7)

(1) A base material and a support made of a silicon wafer,
A step of temporarily fixing via a temporary fixing material having a photothermal conversion layer;
(2) a step of processing the substrate;
(3) Without focusing on the surface of the support opposite to the contact surface with the temporary fixing material,
A method for treating a substrate, comprising: irradiating the temporary fixing material with infrared rays from the support side; and (4) peeling the substrate from the support.   The method for treating a substrate according to claim 1, wherein in the step (3), the infrared ray is an infrared laser.   3. The substrate processing method according to claim 2, wherein in the step (3), the temporary fixing material is irradiated from the support side while scanning with an infrared laser.   The processing method of the base material of Claim 2 or 3 which irradiates an infrared laser focused on the said photothermal conversion layer in the said process (3).   In the step (1), the base material and the support composed of the silicon wafer are placed in the order of the support, the light-to-heat conversion layer, the adhesive layer, and the base material through a temporary fixing material having an adhesive layer and a photothermal conversion layer. The processing method of the base material as described in any one of Claims 1-4 temporarily fixed so that it may become a laminated body which has each layer. A temporary fixing composition for forming a photothermal conversion layer of a temporary fixing material, comprising a cycloolefin polymer and carbon black.   The semiconductor device obtained by the processing method of the base material as described in any one of Claims 1-5.