JP2007191629A - Thermosetting composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermosetting composition excellent in both tackiness and adhesiveness. <P>SOLUTION: The thermosetting composition comprises (A) an organopolysiloxane containing, on average, two or more alkenyl groups per molecule and (B) an organohydrogenpolysiloxane containing at least two SiH bonds per molecule. In this thermosetting composition, its curing reaction is caused at two steps, the first curing reaction is substantially completed at a first temperature or lower and the second curing reaction is initiated at a second temperature higher than the first temperature. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermosetting composition and an adhesive film to which the composition is applied. Specifically, the present invention relates to an adhesive and an adhesive film suitable for the first dicing die-bonding adhesive film, in which the curing reaction occurs in two stages.

  A semiconductor device usually includes a step of adhering a large-diameter silicon wafer to a dicing mount for wafer dicing and adhering it to a dicing tape, and cutting the fixed silicon wafer vertically and horizontally to process it into a semiconductor chip. The semiconductor chip is bonded and fixed to the lead frame using a dicing step, a step of separating the semiconductor chip from the dicing tape, and a curable liquid adhesive (usually referred to as a die bond agent). It is manufactured through a die bonding process.

  Recently, in order to simplify the process and to avoid problems such as contamination of semiconductor parts due to liquid components when using liquid adhesive, the function of dicing tape for fixing silicon wafers and semiconductors A dicing / die bonding adhesive sheet having a function as a die bonding agent for bonding and fixing a chip to a lead frame is used.

  In the dicing process, the dicing / die bonding adhesive sheet needs to be able to securely adhere and hold so that the silicon wafer is not peeled off from the dicing mount. When separating the semiconductor chip, it is necessary to separate the semiconductor chip from the dicing mount together with the semiconductor chip. Next, in the die-bonding step, the film-like material needs to have sufficient adhesive strength to crimp and fix the semiconductor chip on the lead frame. It is necessary to have the ability to firmly bond and fix to the lead frame.

  An adhesive composition containing a polyimide resin is known as a sheet for dicing die bonding (Patent Document 1). However, since the polyimide resin has a high Tg and a high elastic modulus, there have been problems such as the occurrence of cracks due to stress caused by heat between the semiconductor chip and the substrate.

  Silicone adhesives have also been proposed as those having lower Tg and elastic modulus (Patent Documents 2 to 4). However, these are room temperature curable materials that are cross-linked and cured by moisture and moisture in the air, and have a long period of several days to several weeks before obtaining a desired adhesive force, and can be adopted from the viewpoint of productivity. It is not a thing. Furthermore, since the silicone-based pressure-sensitive adhesive is relatively soft, there are problems such as chip position shift and chip skipping during dicing.

On the other hand, a base material coated with solder resist ink is often used as a lead frame for mounting a semiconductor chip. An organopolysiloxane composition that cures by both peroxide curing and hydrosilylation curing is known as a silicone-based adhesive having sufficient adhesion performance to the substrate (Patent Document 5).
JP-A-9-67558 JP 7-53871 A JP 7-53942 A JP-A-7-70541 JP 2005-53966 A

  However, it has been found that the composition described in Patent Document 5 has room for improvement in terms of tackiness (pressure-sensitive adhesiveness) required in the dicing process. Then, an object of this invention is to provide the thermosetting composition excellent in adhesiveness and adhesiveness.

That is, the present invention is as follows.
(A) an organopolysiloxane containing an average of two or more alkenyl groups per molecule, and (B) an organohydrogenpolysiloxane containing at least two SiH bonds in one molecule,
In a thermosetting composition comprising:
The curing reaction occurs in two stages, the first curing reaction is substantially completed below the first temperature, and the second curing reaction starts at a second temperature higher than the first temperature. A thermosetting composition.

  The thermosetting composition of the present invention exhibits tackiness required in the dicing process by the first stage curing and strong adhesiveness by the second stage curing, and is suitably used for a dicing die bond adhesive sheet. .

  In the thermosetting composition of the present invention, the first curing reaction is substantially completed below the first temperature, and the second curing reaction is substantially started at a second temperature higher than the first temperature. It is characterized by doing. Such a curing reaction can be observed as a first heat generation and a second heat generation as shown in the DSC chart of the composition of Example 1 of the present application in FIG. The fact that the reaction is substantially complete can be confirmed by the fact that the exothermic peak returns almost to the baseline visually, and the start of the reaction can be confirmed by the rise of the exothermic peak. Compositions with two curing mechanisms are known as described above. However, compositions in which they occur in stages are not known.

Preferably, the first curing reaction is a hydrosilylation reaction, and the second curing reaction is radical polymerization. The hydrosilylation reaction is substantially complete during the solvent drying step at room temperature to 100 ° C, preferably 70-100 ° C. This can be achieved, for example, by adjusting the type of reaction control agent described later and the amount added. The second curing reaction starts at a temperature above 100 ° C., preferably from 150 ° C. to 190 ° C. This can be achieved, for example, by selecting the type of organic oxide described below and its half-life.

両式中、Ｒ^１は互いに独立に、脂肪属不飽和結合を有さない１価炭化水素基であり、Ｒ^２はアルケニル基を含有する基であり、ｘは０〜３の整数、好ましくは１〜３、より好ましくは２であり、ｍは０以上の整数であり、ｎは１００以上の整数であって、後述する粘度範囲を満たす数であり、ｘとｍの和は１以上であり、ｐは１以上の整数である。 In the thermosetting composition of the present invention, the organopolysiloxane of component (A) contains an alkenyl group bonded to an average of 2 or more silicon atoms per molecule. Preferably, the polyorganosiloxane of component (A) is represented by the following formula (1) or (2), or a mixture thereof.

In both formulas, R ¹ independently of each other is a monovalent hydrocarbon group having no aliphatic unsaturated bond, R ² is a group containing an alkenyl group, and x is an integer of 0 to 3, preferably 1 to 3, more preferably 2, m is an integer of 0 or more, n is an integer of 100 or more and is a number that satisfies the viscosity range described later, and the sum of x and m is 1 or more , P is an integer of 1 or more.

Preferably, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms. For example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group , Tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, octyl group, nonyl group, decyl group and other alkyl groups; vinyl group, allyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, Alkenyl groups such as hexenyl, cyclohexenyl and octenyl; aryl groups such as phenyl, tolyl, xylyl and naphthyl; aralkyl groups such as benzyl, phenylethyl and phenylpropyl; chloromethyl; Bromoethyl group, 3,3,3-trifluoropropyl group, 3-chloropropyl group, cyanoethyl group And a halogen-substituted hydrocarbon group such as a cyano group-substituted hydrocarbon group, and a methyl group and a phenyl group are preferable. Each substituent may be different.

R ² may be present at any position in the organopolysiloxane molecule, but is preferably present at both ends from the viewpoint of curability and physical properties of the cured product. Examples of the alkenyl group include a vinyl group, an allyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a hexenyl group, a cyclohexenyl group, and an octenyl group. Of these, a vinyl group is preferable.

  The properties of the organopolysiloxane (A) are oily or raw rubbery. The oily material preferably has a viscosity at 25 ° C. of 50 mPa · s or more, particularly 100 mPa · s or more. When the viscosity is 50 mPa · s or less, sufficient tackiness may not be obtained. If it is a raw rubber-like one, one having a viscosity in a 30 wt% toluene solution of 100,000 mPa · s or less is preferred.

(B) The organohydrogenpolysiloxane has 2 or more, preferably 3 or more SiH bonds in one molecule, and is represented by the following average composition formula (3).

R ³ _b H _c SiO _{(4-bc) / 2} (3)

In the above formula (3), R ³ is an unsubstituted or substituted monovalent hydrocarbon group bonded to a silicon atom, preferably having 1 to 10 carbon atoms, excluding an aliphatic unsaturated bond, such as a methyl group Alkyl groups such as ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, octyl, nonyl, decyl; phenyl, tolyl Aryl groups such as benzyl group, phenylethyl group and phenylpropyl group; alkyl halide groups such as chloromethyl group, chloropropyl group, bromoethyl group and trifluoropropyl group It is done. Preferably, R ³ is an alkyl group and an aryl group, more preferably a methyl group and a phenyl group. B is 0.7 to 2.1, c is 0.001 to 1.0, and b + c is a positive number satisfying 0.8 to 3.0, preferably b is 1.0 to 2 0.0 and c are 0.01 to 1.0, and b + c is 1.5 to 2.5.

As the molecular structure, various structures such as linear, cyclic, branched, and three-dimensional network structure (resinous) can be used, but the linear structure is preferable. The SiH group may be present at any position in the (B) organohydrogenpolysiloxane molecule. From the viewpoint of physical properties of the obtained silicone rubber and handling workability of the composition, the number of silicon atoms or the degree of polymerization in one molecule is 2 to 1,000, preferably 3 to 300, more preferably 4 to About 150 are desirable, and the viscosity at 25 ° C. is preferably 0.1 to 5,000 mPa · s, more preferably 0.5 to 1,000 mPa · s, and most preferably about 5 to 500 mPa · s. The liquid is used at room temperature (25 ° C.).

  Preferred (B) organohydrogenpolysiloxanes include methylhydrogenpolysiloxane, dimethylsiloxane / methylhydrogensiloxane copolymer, and dimethylsiloxane / methylhydrogensiloxane / methyl having trimethylsiloxy groups at both ends of the molecular chain. Phenylsiloxane copolymer; dimethylpolysiloxane, dimethylsiloxane-methylhydrogensiloxane copolymer, dimethylsiloxane-methylphenylsiloxane copolymer, and methylphenylpolysiloxane having dimethylhydrogensiloxy groups at both ends of the molecular chain These mixtures are exemplified. In addition, these copolymers may have a branch.

In (B) organohydrogenpolysiloxane, the amount (mol) of SiH bonds is (hereinafter referred to as “H / Vi (mol / mol)” relative to the amount (mol) of alkenyl group in (A) organopolysiloxane. In the composition in an amount of 0.01 to 0.7, preferably 0.05 to 0.5. If it is in this range, suitable adhesiveness can be obtained.

  Examples of (C1) hydrosilylation catalysts include platinum, palladium, rhodium, etc., chloroplatinic acid, alcohol-modified chloroplatinic acid, coordination compounds of chloroplatinic acid and olefins, vinylsiloxane or acetylene compounds, tetrakis (triphenyl) Platinum group metals such as phosphine) palladium and chlorotris (triphenylphosphine) rhodium or these compounds are used, and platinum compounds are particularly preferred.

The blending amount of the (C1) hydrosilylation catalyst is preferably 1 to 500 ppm, more preferably 10 to 100 ppm as the amount of the metal element with respect to the total amount of the components (A) and (B). . If the blending amount is less than the lower limit, the reaction may be remarkably slow or may not be cured. If the blending amount exceeds the upper limit, the heat resistance of the cured polysiloxane composition may be reduced.

  As the (C2) radical polymerization catalyst, an organic oxide used for curing silicone rubber is preferably used. For example, benzoyl peroxide, dicumyl peroxide, t-butylbenzoate, t-butylperoxybenzoate, Di-t-butyl peroxide, di-t-hexyl peroxide, t-butylcumyl peroxide, 1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane, 2,5-dimethyl- 2,5-bis (t-butylperoxy) hexane, 1,6-bis (t-butylperoxycarboxy) hexane, di- (4-methylbenzoyl) peroxide, di- (2-methylbenzoyl) peroxide , T-butylperoxyisopropyl monocarbonate, di- (2-t-butyl Oxy) benzene, and the like. Of these, those having a half-life of 10 hours and a temperature of 90 ° C. or more are more preferred, and most preferably those having a previous temperature of 110 ° C. or more, such as dicumyl peroxide, di-t-butyl peroxide, -T-hexyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, di- (2-t-butylperoxyisopropyl) benzene are used .

  The blending amount of (C2) is 0.1 to 20 parts by weight, preferably 0.2 to 15 parts by weight, more preferably about 0.5 to 10 parts by weight with respect to 100 parts by weight of (A) organopolysiloxane. is there. If the blending amount is less than the lower limit value, sufficient crosslinking cannot be obtained. Even if the blending amount exceeds the upper limit value, the cost increases, and it is difficult to improve the performance commensurate with the increase.

The thermosetting composition of the present invention may contain (D) finely divided silica as a reinforcing agent. By containing finely divided silica, when applied to a film, a film having high strength is obtained. The (D) microparticulate silica, specific surface area (BET method) is 50 m ² / g or more, preferably 10 to 400 m ² / g, more preferably used are those which are 50 to 300 m ² / g. When the specific surface area is less than 10 m ² / g, it is difficult to provide satisfactory strength characteristics.

  As (D) finely divided silica, known ones conventionally used as reinforcing fillers for silicone rubber can be used, and examples thereof include precipitated silica, fumed silica, and fired silica. These can be used alone or in combination of two or more. Such finely divided silica may be used as it is, but for the good fluidity of the composition of the present invention, silazanes such as hexamethyldisilazane, methyltrimethoxysilane, ethyltrimethoxysilane, propyl Trimethoxysilane, butyltrimethoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, trimethylmethoxysilane, triethylmethoxysilane, vinyltris (methoxyethoxy) silane, trimethylchlorosilane, dimethyldichlorosilane, divinyl Surface treatment with silane coupling agents such as dimethoxysilane and chloropropyltrimethoxysilane, organosilicon compounds such as polymethylsiloxane and organohydrogenpolysiloxane Ri, it is preferable to use those hydrophobic.

(D) The compounding quantity of a component is 1-50 mass parts with respect to 100 mass parts of (A) component organopolysiloxane, Preferably it is 1-30 mass parts. If the blending amount exceeds the above upper limit, blending becomes difficult and it becomes difficult to form a film.

  The thermosetting composition of this invention may contain the (E) adhesive improvement component for improving the adhesiveness with respect to a base material. As the improving component, alkenyl group, epoxy group, (meth) acryl group, (meth) acryloxy group, alkoxy group, alkoxysilyl group, isocyanate group, SiH bond, ester group, anhydrous carboxyl group, amino group, and amide group , Organosilicon compounds, organotitanium compounds, other organic compounds, and mixtures thereof containing at least one, preferably two or more functional groups.

  Examples of the organosilicon compound include organosilanes having one or more functional groups selected from the above functional groups, siloxane oligomers having a linear or cyclic structure having 3 to 50 silicon atoms, particularly 5 to 20 silicon, and triallyl. Examples include (alkoxy) silyl-modified products of isocyanurate, siloxane derivatives thereof, and the like.

  Examples of non-silicone organic compounds include organic compounds having one alkenyl group and at least one ester group in the molecule, such as allyl esters of unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and vinyl acetic acid, and benzoic acid. (Non-silicone) organic compounds such as allyl esters such as acid allyl ester, phthalic acid diallyl ester, pyromellitic acid tetraallyl ester and alkyl acid allyl ester. Moreover, you may add epoxy group ring-opening catalysts, such as organometallic chelate, an amine type, an amide type, an imidazole type, and an acid anhydride type.

  Examples of the organic titanium compound (titanate coupling agent) include tetra i-propyl titanate, tetra n-butyl titanate, butyl titanate dimer, tetrastearyl titanate, triethanolamine titanate, titanium acetylacetonate, titanium ethyl acetoacetate, and titanium. Lactate and octylene glycol titanate, isopropyl tristearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, bis (dioctyl pyrophosphate) ethylene titanate, tetrabutoxy titanium Tetrakis (2-ethylhexyloxy) titanium, La stearyl oxytitanium, titanium stearate, tetra octyloxy titanium, titanium -i- propoxy octylene glycolate, titanium ethyl acetonate, titanium lacto sulfonates, or their oligomers, polymers, and the like.

  In addition, when using the compound which has an epoxy group as (E) adhesive improvement agent, it is preferable that the epoxy equivalent of this compound is 100-5,000 g / mol, especially 150-3,000 g / mol.

  Preferably, an organosilicon compound having an epoxy equivalent in the above range and having at least one alkenyl group or SiH group and an alkoxy group in one molecule, and having at least 12 carbon atoms in one molecule One or more selected from titanium compounds and organosilicon compounds containing one or more nitrogen atoms in one molecule are used.

  (E) The compounding quantity of a component is 0.1-20 mass parts with respect to 100 mass parts of (A) component organopolysiloxane, Preferably it is 0.5-15 mass parts. When the blending amount is less than the lower limit value, it is difficult to obtain sufficient adhesive force, and even if the blending amount exceeds the upper limit value, the performance cannot be improved according to the increase in cost.

The composition of the present invention may contain (F) an organopolysiloxane resin. Here, “resin” means a material that is semi-solid or solid at room temperature. The organopolysiloxane resist increases the tackiness and transferability of the adhesive sheet of the present invention depending on the type of substrate such as a wafer or die frame.

The component (F) includes a unit represented by R ₃ SiO _1/2 (hereinafter referred to as “M unit”) and a SiO ₂ unit (hereinafter referred to as “Q unit”), and M unit / Q It is an organopolysiloxane resin or a mixture thereof containing both units in a ratio such that the molar ratio of units is 0.6 to 1.7, preferably 0.6 to 1.0. If the molar ratio is less than the lower limit, the adhesive strength and tackiness of the adhesive film of the present invention may be reduced. Conversely, if the upper limit is exceeded, the adhesive strength is still poor, Holding force may decrease. R is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, such as an alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group; A cycloalkyl group such as a group; an aryl group such as a phenyl group; an alkenyl group such as a vinyl group, an allyl group, and a hexenyl group. Among these, a methyl group is preferable.

(F) The organopolysiloxane resin may have a hydroxyl group (silanol group) bonded to a silicon atom. The hydroxyl group content is preferably about 0.02 to 0.05 mol% of (F) organopolysiloxane resin. When the content exceeds the above amount, the thermosetting property of the composition of the present invention may be lowered, which is not preferable.

The organopolysiloxane resin (F) is a trifunctional unit represented by RSiO _3/2 and / or a bifunctional unit represented by R ₂ SiO (in the range not impairing the object and effect of the present invention) In each formula, R may be the same as described above).

Preferred (F) organopolysiloxane resin is an organopolysiloxane having (CH ₃ ) ₃ SiO _1/2 units / SiO ₂ units of 1 / 0.75 (mol / mol) and containing about 1 mol% of hydroxyl groups. Resin is mentioned.

  When the component (A) and the component (F) are used in combination, both components may be simply blended in the composition of the present invention, but when the component (F) has a hydroxyl group, both components May be blended as a partial condensate by subjecting both to a condensation reaction by a known method. When conducting the condensation reaction, dissolve both components in a solvent such as toluene in which both components are soluble, and use a basic or alkaline catalyst such as ammonia under conditions of room temperature to reflux temperature. You can make it react.

  The use ratio of the component (A) to the component (F) is such that the weight ratio of the component (A) / the component (F) is preferably 30-70 / 70-30, more preferably 40 / 60-60 / The range is 40.

  The composition of the present invention may contain a reaction control agent that suppresses the hydrosilylation reaction. The amount is appropriately adjusted depending on the desired storage stability and the desired first temperature. For example, the amount is set such that curing is suppressed at the temperature applied to the film substrate and hydrosilylation is completed at the temperature at which the solvent in the composition is evaporated. The amount varies depending on the resin in the composition, its reactivity, etc., but is typically 1: 1 or more by weight.

Examples of the control agent include phosphorus-containing compounds such as triphenylphosphine; nitrogen-containing compounds such as tributylamine, tetramethylethylenediamine, and benzotriazole; sulfur-containing compounds, acetylene compounds, compounds containing two or more alkenyl groups, hydroperoxy Examples thereof include compounds and maleic acid derivatives, preferably acetylene-based compounds having a hydroxyl group, such as 3-methyl-1-butyn-3-ol and 1-ethynyl-1-cyclohexanol. . Since the reaction inhibitory effects of these control agents are different from each other, the optimum amount is adjusted and used for each individual.

  The composition of the present invention may contain various fillers as long as the object of the present invention is not impaired. For example, crystalline silica, calcined spherical silica, hollow filler, silsesquioxane, fumed titanium dioxide, magnesium oxide, zinc oxide, iron oxide, aluminum hydroxide, magnesium carbonate, calcium carbonate, zinc carbonate, layered mica, carbon black, Examples include inorganic fillers such as diatomaceous earth and glass fibers, and fillers obtained by surface-treating these fillers with organosilicon compounds such as organoalkoxysilane compounds, organochlorosilane compounds, organosilazane compounds, and low molecular weight siloxane compounds. . Moreover, silicone rubber powder, silicone resin powder, etc. are mentioned. In particular, crystalline silica, baked spherical silica, silicone rubber powder, silicone resin powder, and the like are effective in reducing the volume expansion coefficient and preventing warpage of the semiconductor package.

  Furthermore, the composition of this invention may contain a well-known additive in the range which does not impair the objective of this invention. For example, an organic solvent, an anti-creep hardening agent, a plasticizer, a thixotropic agent, a pigment, a dye, an antifungal agent and the like can be blended. In particular, when forming into a film, it is preferable to dilute with an organic solvent. Examples of the organic solvent include toluene, xylene, hexane, heptane, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, and the like. The amount of the organic solvent used may be adjusted according to the desired viscosity of the resulting dilution, but is usually 20 to 90 parts by weight, preferably 30 to 80 parts by weight, based on 100 parts by weight of the total solid content. About a part.

 The composition of the present invention can be produced by mixing the above components at once, or by mixing the components (A) and (D) while heating and then mixing other components at room temperature. .

  The composition of the present invention can be used as a pressure-sensitive adhesive in a state before the second curing reaction, and exhibits good adhesiveness to various substrates. For example, the composition of the present invention is applied to a dicing mount when manufacturing a semiconductor device, and can be effectively used as an adhesive material for fixing a silicon wafer.

  In addition, the composition of the present invention exhibits a strong adhesive force by causing a second curing reaction. For example, in a die bonding process when manufacturing a semiconductor device, a semiconductor chip integrally having an adhesive layer is pressure-bonded to a lead frame, and then subjected to heat treatment, whereby the cured layer of the adhesive of the present invention is formed. Thus, a semiconductor device in which the base material and the semiconductor chip are firmly bonded can be manufactured. The composition of the present invention can be used subsequently in both the dicing step and the die bonding step.

The composition of the present invention may be applied onto a film. The composition of the present invention is applied on a base film so as to have a predetermined thickness, heated to remove the solvent, and the first reaction is completed to form an adhesive layer. The first reaction is preferably completed during solvent removal. If desired, another base film is pressure-bonded onto the adhesive layer to form a protective film. The obtained laminated film having a two- or three-layer structure is subjected to a necessary process such as cutting.

  As the substrate film, films such as polyethylene, polypropylene, polyester, polyamide, polyimide, polyamideimide, polyetherimide, polytetrafluoroethylene, paper, metal foil, and the like can be used. A release agent may be applied to these film surfaces so that the diced chips can be picked up from the base film without any problem.

  When using the above sheet or tape, if it has a two-layer structure, after the pressure-sensitive adhesive surface is pressure-bonded to the target substrate, the peelable film is removed, and another substrate is pressure-bonded onto the exposed pressure-sensitive adhesive surface. And both base materials are fixed through an adhesive. In the case of a three-layer structure, one peelable film is removed, and after the pressure-sensitive adhesive surface is pressure-bonded to the target substrate, the other peelable film is removed, and on the exposed pressure-sensitive adhesive surface, Crimp and fix other substrates.

The thickness of the pressure-sensitive adhesive / adhesive layer of the present invention is not particularly limited and can be set according to the purpose, but is typically 0.01 to 2.0 mm, more typically about 0.01 to 1.0 mm. is there.

  When the composition of the present invention is diluted with a solvent, the drying / removal conditions are preferably 2 hours or more at room temperature, 1 to 20 minutes at 40 to 130 ° C., and more preferably 50 to It is good to set it as 120 degreeC x 1 to 20 minutes. If it is only dry removal, milder conditions are preferred.

  Further, the amount of volatile components contained in the adhesive layer is less than 1% by weight so that voids (voids) are not generated in the cured product in the heat curing step of the adhesive of the present invention. It is preferable.

  The conditions for the radical polymerization reaction, which is the second curing reaction, are adjusted depending on the 10-hour half-life of the (C2) radical polymerization catalyst, but preferably at 100 to 250 ° C. for 15 to 60 minutes, more preferably 15 to 60 minutes at 120 to 230 ° C.

  Examples of the substrate to which the composition of the present invention exhibits excellent adhesiveness and adhesiveness include metals such as Fe, Al, Cr, Ni, Si, Cu, Ag, and Au; glass, silicon nitride And inorganic materials such as silicon carbide or ceramics; and substrates made of organic materials such as epoxy resin, bakelite, polyimide, polyamide, polyester, and silicone resin.

  The above-mentioned adhesive / adhesive film, particularly a film having a three-layer structure, is suitable as a dicing / die-bonding adhesive film. The usage will be described. First, a dicing mount is prepared in which the surface on which the silicon wafer is mounted has sufficient adhesion to the base film of the film. Alternatively, the base film may be peeled off and adhered to the dicing mount. The adhesive film is cut out into a shape corresponding to the dicing mount, and is stacked and adhered along the dicing mount so as to be fixed. Next, the peelable film on the side not sticking to the dicing mount is peeled off, and a silicon wafer is stacked on the exposed adhesive layer and fixed by pressure bonding. Thereafter, after the silicon wafer is diced, each cut semiconductor piece is individually taken out. At this time, the pressure-sensitive adhesive layer is easily peeled off from the peelable film on the dicing mount surface and taken out integrally with the semiconductor chip. In this way, a semiconductor chip having an adhesive layer on one side can be obtained.

  Subsequently, after the semiconductor chip is pressure-bonded to the prepared lead frame via the adhesive layer, the required heat treatment is performed to cure the adhesive layer, thereby bonding the semiconductor chip to the lead frame. In this manner, a semiconductor device in which the base material and the semiconductor chip are firmly bonded via the cured layer of the adhesive of the present invention can be manufactured with high productivity.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to these Examples. In addition, a part shows a mass part and the viscosity is a value of 25 degreeC in the following example.

 The adhesion improvers (i) to (iii) used in the following examples are as follows.

In the following, H / Vi represents the molar ratio of (H) SiH group to (A) vinyl group in organopolysiloxane, 1-ethynylcyclohexanol as the control agent, and platinum chloride as the hydrosilylation reaction catalyst. A complex of acid and divinyltetramethyldisiloxane was used, respectively.

[Example 1]
50 parts of dimethylpolysiloxane having vinyl groups at both ends of the molecular chain, an average degree of polymerization of about 10,000, and 0.002 mol of vinyl groups per 100 g, and a specific surface area of 120 m ² / g surface-treated with trimethylsilyl groups 17 parts of hydrophobic silica, dimethyl siloxane / methyl hydrogen siloxane copolymer (MD ₈ ^DH ₇ M, with SiH bond content) having SiH bonds at both ends and side chains of the molecule and having a viscosity of 12 mPa · s 0.54 mol / 100 g of the polymer) in an amount of H / Vi = 0.3, 0.02 part of a control agent, and 30 ppm of platinum as the platinum component with respect to the total amount of the components (A) and (B). Hydrosilylation reaction catalyst, 5 parts of di- (2-tert-butylperoxyisopropyl) benzene and 1.5 parts of adhesion improver (i) are mixed with 100 parts of component (A) to obtain a mixture The composition A was prepared by dissolving in toluene so that the concentration of the solid content was 30%. In composition A, the hydrosilylation reaction was completed at 100 ° C. or lower, and the organic oxide was cured at 150 ° C. or higher. FIG. 1 shows a DSC chart measured at a heating rate of 10 ° C./min in a nitrogen atmosphere. In addition, in the same chart, the caloric curve shown on the lower side is a curve of a composition which is different from the composition of Example 1 only in that it does not contain a hydrosilylation catalyst. In the above, M is a (CH ₃ ) ₃ SiO _1/2 unit, D is a (CH ₃ ) ₂ SiO unit, and ^DH is a (CH ₃ ) HSiO unit.

[Example 2]
As dimethylpolysiloxane, 100 parts of dimethylpolysiloxane having hydroxyl groups at both ends of the molecular chain having an average degree of polymerization of about 10,000 and 0.005 mol of vinyl groups per 100 g, in an amount of H / Vi = 0.5. The addition reaction was completed at 100 ° C. or lower and 150 ° C. or higher in the same manner as in Example 1 except that 1.5 parts of dimethylsiloxane / methylhydrogensiloxane copolymer and adhesion improver (ii) were used. To obtain a composition B which is cured with an organic oxide.

[Example 3]
As dimethylpolysiloxane, 100 parts of dimethylpolysiloxane having hydroxyl groups at both ends of the molecular chain having an average polymerization degree of about 10,000 and 0.005 mol of vinyl group per 100 g, and 3 parts of an adhesion improver (iii) are used. In the same manner as in Example 1, a composition C was obtained in which the addition reaction was completed at 100 ° C. or lower and the organic oxide was cured at 150 ° C. or higher.

[Example 4]
As dimethylpolysiloxane, 70 parts of dimethylpolysiloxane having hydroxyl groups at both ends of the molecular chain having an average degree of polymerization of about 10,000 and 0.005 mol of vinyl groups per 100 g, dimethyl having a SiH group content of 1.14% by mass 30 parts of a methylpolysiloxane resin comprising siloxane / methylhydrogensiloxane copolymer, 3 parts of adhesion improver (iii), and a ratio of 0.75 mole of (CH ₃ ) SiO _1/2 units and 1 mole of SiO ₂ units Except for further blending, in the same manner as in Example 1, a composition D was obtained in which the addition reaction was completed at 100 ° C. or lower and the organic oxide was cured at 150 ° C. or higher.

[Example 5]
As dimethylpolysiloxane, 70 parts of dimethylpolysiloxane having hydroxyl groups at both ends of the molecular chain having an average degree of polymerization of about 10,000 and 0.005 mol of vinyl group per 100 g, and 3 parts of an adhesion improver (iii) are used. Example 1 except that 0.5 part of octyl titanate and 30 parts of methylpolysiloxane resin composed of 0.75 moles of (CH ₃ ) ₃ SiO _1/2 units and 1 mole of SiO ₂ units were further blended Thus, the addition reaction was completed at 100 ° C. or lower, and a composition E that was cured with an organic oxide at 150 ° C. or higher was obtained.

[Comparative Example 1]
According to Patent Document 5 and Example 6, a raw rubber-like dimethylpolysiloxane having hydroxyl groups at both ends of a molecular chain, the viscosity of a 30 wt% toluene solution at 25 ° C. is 42,000 mPa · s, and per 100 g 50 parts of dimethylpolysiloxane having 0.002 mol of vinyl group and 50 parts of methylpolysiloxane resin having a ratio of 0.75 mol of (CH ₃ ) SiO _1/2 units and 1 mol of SiO ₂ units are dissolved in 100 parts of toluene. 100 parts of the solution, 1.6 parts of an adhesion improver represented by the following formula (4), 0.8 part of bis (3-methylbenzoyl) peroxide, organohydro represented by the following formula (5) 1.29 parts of genpolysiloxane and hydrosilylation reaction catalyst in the total resin weight excluding toluene and bis (3-methylbenzoyl) peroxide , The amount of platinum content is 10ppm, and 3-methyl-1-butyn-3 a mixture of 0.05 parts ol was prepared composition F.

[Reference Example 1]
In the composition of Example 5, Composition G was prepared in the same manner as in Example 5 except that the amount of the control agent was 0.1 parts and the hydrosilylation reaction was adjusted to start at 150 ° C. or higher.

[Reference Example 2]
Composition H was prepared in the same manner as in Example 5 except that the adhesion improver (iii) was not blended.

Each of the prepared compositions was applied onto a 50 μm thick PET film coated with a fluorine-containing silicone release agent, left at room temperature for 10 minutes, and then heat-treated at 80 ° C. for 10 minutes to obtain a thickness. An adhesive layer of about 50 μm was formed. However, Reference Example 1 was only dried and not cured. Next, the PET film on which the adhesive layer was formed was cut into a shape of 25 mm long × 10 mm wide and subjected to the following tests.

Each test method is as follows.
Transferability When PET of the above film is fixed on a dicing mount, a 300-micron-thick 8-inch wafer is fixed on the adhesive layer, cut into 10 mm square with a dicer (manufactured by Disco), and then picked up, The adhesive layer transferred to the wafer chip was A, and the other was B.
Chip position deviation After cutting a 300-micron thick 8-inch wafer into a 10 mm square with a dicer (manufactured by Disco), the wafer is rotated at 3000 rpm, and air blowing and water washing are performed for 5 minutes. One was A and the other was B.
Chip skipping A chip misalignment test where no chip skipping occurred after cleaning was designated as A, and those other than that were designated as B.
Adhesion The PET film of the above film was peeled off, and the adhesive layer was attached to the end of a SUS test piece having a width of 25 mm (10 × 25 mm). Next, another PET film is peeled off, and a UV curable solder resist (trade name: PSR4000 AUS308, manufactured by Taiyo Ink Manufacturing Co., Ltd.) layer is formed on the BT resin on the exposed adhesive surface. Overlap the edge of the substrate, sandwich the adhesive layer, and test by applying a weight of 2000g to the part where the end of the SUS test piece, adhesive layer and unit substrate are laminated for 1 minute. Got the body. Then, it was placed in a heating furnace and heated at 1700 ° C. for 60 minutes to cure the adhesive layer. Thereafter, the bonded specimen was measured for shear adhesive strength (kg / cm ² ) using a shear adhesive strength measuring device in accordance with JIS K6850.
Adhesion durability The bonded specimens were stored at 80C and 90% RH for 7 days and then subjected to a shear test in the same manner.

表１に示すように、本発明の組成物は第１段階の硬化により、チップ位置ずれ及びチップ飛びの無い良好な粘着層を与える。また、該粘着層は転写性に優れ、基板に粘着された後に、第２の加熱硬化を経て強固な接着層を与える。これに対して、比較例１の組成物および参考例１の組成物は、粘着力が十分ではなく、チップ飛び、及び位置ずれが生じた。

As shown in Table 1, the composition of the present invention gives a good pressure-sensitive adhesive layer free from chip displacement and chip skipping by the first stage curing. The adhesive layer is excellent in transferability, and after being adhered to the substrate, it gives a strong adhesive layer through second heat curing. On the other hand, the composition of Comparative Example 1 and the composition of Reference Example 1 did not have sufficient adhesive strength, and chip fly and positional deviation occurred.

  The thermosetting composition of the present invention is suitably used for applications requiring both tackiness and adhesiveness, and is particularly suitable as a dicing die-bonding adhesive tape.

2 is a DSC chart of the composition prepared in Example 1 and a composition that differs from the composition only in that it does not contain a hydrosilylation catalyst.

Claims (10)

(A) an organopolysiloxane containing an average of two or more alkenyl groups per molecule, and (B) an organohydrogenpolysiloxane containing at least two SiH bonds in one molecule,
In a thermosetting composition comprising:
The curing reaction occurs in two stages, the first curing reaction is substantially completed below the first temperature, and the second curing reaction starts at a second temperature higher than the first temperature. A thermosetting composition. The thermosetting composition is
(C1) a hydrosilylation catalyst and (C2) a radical polymerization catalyst are further included, the first curing reaction is a hydrosilylation reaction, the second curing reaction is a radical polymerization, and (C2) the radical polymerization catalyst has a half-life. The thermosetting composition according to claim 1, wherein the temperature is 10 hours, and the temperature is 90 ° C. or more. (C1) The thermosetting composition according to claim 2, wherein the hydrosilylation catalyst is platinum or a platinum compound.  (B) The ratio of the amount of SiH bonds in the organohydrogenpolysiloxane to the amount of alkenyl groups in (A) the organopolysiloxane is 0.01 to 0.7 mol / mol. The thermosetting composition of any one of 1-3.   The thermosetting composition according to any one of claims 1 to 4, wherein the first temperature is 70 to 100 ° C, and the second temperature is 150 to 190 ° C. The thermosetting composition according to any one of claims 1 to 5, further comprising (D) fine powdery silica having a specific surface area (BET method) of 10 m ² / g or more. It further includes an organic compound having an SiH bond, an alkenyl group, and at least one group selected from an epoxy group, an alkoxysilyl group, an acrylic group, a methacryl group, an ester group, an anhydrous carboxyl group, an isocyanate group, an amino group, and an amide group. The thermosetting composition according to any one of claims 1 to 6.   The film formed by the thermosetting composition of any one of Claims 1-7 being applied to at least one side.   9. The film according to claim 8, wherein the applied thermosetting composition is in a state after the first curing reaction. A semiconductor device in which a semiconductor chip is fixed on a substrate through the thermosetting composition according to any one of claims 1 to 7, wherein the semiconductor chip is in a state after the first curing reaction or after the second curing reaction. .

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