JP2016017122A - Thermosetting resin composition for semiconductor bonding and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting resin composition for semiconductor bonding which has excellent bleeding resistance and high adhesion, and a semiconductor device having excellent solder crack resistance.SOLUTION: The thermosetting resin composition for semiconductor bonding contains (A) an epoxy resin, (B) a sulfur-containing hemiacetal ester derivative (a carboxylic acid derivative in which a carboxyl group is made thermally latent by a vinyl ether compound), (C) an amine-based curing agent, (D) an imidazole-based curing accelerator, (E) a filler, and (F) a reactive diluent and/or an organic solvent. The semiconductor device is obtained using the resin composition.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a thermosetting resin composition for semiconductor bonding and a semiconductor device using the same.

  In a semiconductor device, a process of fixing a semiconductor element (hereinafter also referred to as a semiconductor chip) such as an LED, IC, LSI or the like to a predetermined portion on a thin metal plate (lead frame) is an important process that affects the reliability of the semiconductor device. one of. Conventionally, as this connection method, a method of using a paste-like resin composition in which a filler is dispersed in an organic material as an adhesive is known.

  The resin composition used in this bonding technique is required to have excellent adhesion between the semiconductor element and the lead frame, and to have a low elastic modulus to alleviate the difference in linear expansion coefficient between the semiconductor element and the lead frame. In order to improve adhesion, various additives typified by silane coupling agents are used (see, for example, Patent Document 1).

JP 2009-209246 A

  However, additives typified by silane coupling agents have limitations in formulation, such as bleeding in coating and curing because of poor solubility in many organic solvents and compatibility with various resins.

  On the other hand, sulfur-containing carboxylic acids having a sulfur atom and further having a carboxyl group or the like that reacts with an epoxy group are considered as excellent adhesion imparting agents, particularly in adhesion to a noble metal interface. Is a solid at room temperature and has a problem in versatility because of its low solubility in many organic solvents and low compatibility with various resins.

  Furthermore, since a carboxyl group and a reactive group such as a reactive diluent are likely to react, a composition containing a sulfur-containing carboxylic acid and a compound containing the reactive group may gel during storage. There were problems with its stability, such as shortening the pot life from blending to use.

  Accordingly, the present invention provides a resin composition having improved adhesion characteristics to various precious metal plating surfaces and a highly reliable solder reflow resistance by using the resin composition as a die attach paste for semiconductors. An object is to provide a semiconductor device.

  The present inventors have been made to meet the above-mentioned problems, and in a thermosetting resin composition based on an epoxy resin, a sulfur-containing hemiacetal ester derivative (a carboxylic acid having a carboxyl group thermally latentized by a vinyl ether compound). By using the derivative), it was found that the adhesion characteristics to various noble metal plating surfaces could be improved, and the present invention was completed.

  That is, the thermosetting resin composition for semiconductor bonding of the present invention comprises (A) an epoxy resin, (B) a sulfur-containing hemiacetal ester derivative, (C) an amine curing agent, and (D) an imidazole curing acceleration. And (E) a filler, and (F) a reactive diluent and / or an organic solvent.

  The semiconductor device of the present invention is characterized in that a semiconductor element is bonded onto a semiconductor element support member by the above thermosetting resin composition for bonding semiconductors.

  According to the thermosetting resin composition for semiconductor bonding of the present invention, the occurrence of bleeding in bonding can be suppressed, and the resin composition has high adhesion properties with respect to various noble metal platings. Since a semiconductor device in which a semiconductor element is bonded to a substrate using an excellent solder reflow resistance, a highly reliable semiconductor device can be obtained.

It is sectional drawing which shows the semiconductor device which is one Embodiment of this invention.

Hereinafter, the present invention will be described in detail.
As the epoxy resin of component (A) used in the present invention, any known epoxy resin having two or more epoxy groups can be used. Among these, a liquid resin is preferable, and a resin that is liquid at room temperature (25 ° C.) is more preferable.

  Examples of the epoxy resin include bisphenol type epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, and bisphenol S type epoxy resin; novolak type epoxy resins such as phenol novolak type epoxy resin and alkylphenol novolak type epoxy resin; Biphenol type epoxy resin; Naphthalene type epoxy resin; Dicyclopentadiene type epoxy resin; Epoxidized product derived from condensate of phenols and aromatic aldehyde having phenolic hydroxyl group, or bromine atom-containing epoxy resin or phosphorus atom content Examples of the epoxy resin include hetero ring-containing epoxy resins such as triglycidyl isocyanurate; and known and commonly used epoxy resins such as alicyclic epoxy resins. These may be used singly or in combination of two or more.

  The component (B) sulfur-containing hemiacetal ester derivative used in the present invention is a hemiacetal ester derivative having an organic group containing a sulfur atom. This hemiacetal ester derivative is a compound obtained by reacting a carboxylic acid with a vinyl ether compound, and is a carboxylic acid derivative having a carboxyl group thermally latentized by the vinyl ether compound. This sulfur-containing hemiacetal ester derivative preferably has a sulfur atom in the form of a disulfide bond. Moreover, it is preferable that this (B) component is also liquid at room temperature similarly to (A) component.

  This sulfur-containing hemiacetal ester derivative of component (B) contains a sulfur atom, which improves the adhesion by forming a noble metal-sulfur bond. In addition, since this derivative has a hemiacetal ester structure, it is reactive with the epoxy resin (A) and can be incorporated into the resin skeleton to effectively exhibit the above characteristics and effectively prevent bleeding. it can.

（式中、Ｒ^１は水素原子、若しくは硫黄原子及び炭素原子を含有する１価の有機基、Ｒ^２は硫黄原子及び炭素原子を含有する１価の有機基又はＲ^１とＲ^２は一体となって硫黄原子及び炭素原子を含有する複素環基を表し、Ｒ^３は炭素数１〜１８の１価の炭化水素基を表し、Ａｒは炭素数６〜３０の２価の芳香族炭化水素基を表し、ｎは１〜２０の正の整数を表す。）が好ましいものとして挙げられる。これらは１種を単独で又は２種以上を混合して使用してもよい。 The sulfur-containing hemiacetal ester derivative is, for example, a compound represented by the following general formula (1a), (1b) or (1c)

(In the formula, R ¹ is a hydrogen atom or a monovalent organic group containing a sulfur atom and a carbon atom, R ² is a monovalent organic group containing a sulfur atom and a carbon atom, or R ¹ and R ² are united. And represents a heterocyclic group containing a sulfur atom and a carbon atom, R ³ represents a monovalent hydrocarbon group having 1 to 18 carbon atoms, and Ar represents a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms. And n represents a positive integer of 1 to 20). You may use these individually by 1 type or in mixture of 2 or more types.

Here, when R ¹ and R ² are a monovalent organic group, an organic group having a chain length of 2 to 19 containing a sulfur atom and a carbon atom is preferable. It may be in the shape. The sulfur atom may be directly bonded to the carbon atom to which the organic group is bonded, may be present in the chain of the organic group, or may be present at the end of the organic group. Further, R ¹ and R ² are preferably a group represented by —S—R ⁵ (where R ⁵ represents a hydrocarbon group having 1 to 18 carbon atoms). Further, when R ¹ and R ² together form a heterocyclic group, it is preferably a heterocyclic group containing a 5- or 6-membered sulfur atom and a carbon atom. At this time, it is more preferable that the monovalent organic group and the integrally formed heterocyclic group contain a sulfur atom in the form of a disulfide bond.

  Ar includes, for example, a divalent aromatic hydrocarbon group such as a phenylene group, a naphthylene group, or a biphenylene group, and the aromatic ring may have a substituent. Preferred examples of this substituent include a nitro group, a methoxy group, an ethoxy group, and a t-butyl group.

（式中、Ｒ^１〜Ｒ^３及びｎは、それぞれ上記と同一の基、数値を表す。） The sulfur-containing hemiacetal ester derivative of the component (B) includes, for example, a sulfur-containing carboxylic acid having an organic group containing a sulfur atom represented by the following general formula (2a), as shown in the following reaction formula: It can be produced by addition reaction (blocking) with a vinyl ether compound represented by the following general formula (3). That is, the sulfur-containing hemiacetal ester derivative represented by the general formula (1a) is obtained by reacting the carboxyl group of the sulfur-containing carboxylic acid with the carbon-carbon double bond of the vinyl ether compound. This reaction proceeds relatively easily, and a sulfur-containing hemiacetal ester derivative is obtained in good yield.

(In the formula, R ^{1 to} R ³ and n each represent the same group and numerical value as described above.)

  The sulfur-containing hemiacetal ester derivatives represented by the above general formulas (1b) and (1c) also use a sulfur-containing carboxylic acid having a structure corresponding to the target compound instead of the general formula (2a) as a raw material compound. Can be produced by the same reaction.

  Since this reaction is an equilibrium reaction, the use of a slightly larger amount of vinyl ether compound relative to the sulfur-containing carboxylic acid can accelerate the reaction and improve the yield of the target compound. Specifically, the molar equivalent ratio of the carbon-carbon double bond of the vinyl ether compound to the carboxyl group of the sulfur-containing carboxylic acid [molar equivalent ratio of (carbon-carbon double bond / carboxyl group)] is 1/1 to 2. / 1 is desirable. When this molar equivalent ratio exceeds 2/1, the reaction temperature cannot be increased, the reaction may not proceed further, and the production cost also increases. In addition, it can also be made to react partially according to a use, In that case, molar equivalent ratio can also be set to 0.5 / 1-1/1.

  Examples of the sulfur-containing carboxylic acid include 3,3′-thiodipropionic acid, dithiodipropionic acid, thioctic acid, dithiosalicylic acid, dithiodiglycolic acid, 4,4′-dithiobutyric acid, 5,5′- There are dithiobis (2-nitrobenzoic acid), 3- (methylthio) propionic acid, 3- (dodecylthio) propionic acid and 2- (methylthio) benzoic acid.

（式中、Ｒ^３は炭素数１〜１８の炭化水素基である。）で表されるものを意味する。 The vinyl ether compound used in the present invention has the following general formula (3):

(Wherein R ³ is a hydrocarbon group having 1 to 18 carbon atoms).

  Specific examples of the compound represented by the above formula (3) include, for example, methyl vinyl ether, ethyl vinyl ether, isopropyl vinyl ether, n-propyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, 2-ethylhexyl vinyl ether, Examples include aliphatic monovinyl ether compounds such as cyclohexyl vinyl ether. Further, as the vinyl ether compound, 2,3-dihydrofuran, 3,4-dihydrofuran, 2,3-dihydro-2H-pyran, 3,4-dihydro-2H-pyran, 3,4-dihydro- 2-methoxy-2H-pyran, 3,4-dihydro-4,4-dimethyl-2H-pyran-2-one, 3,4-dihydro-2-ethoxy-2H-pyran, 3,4-dihydro-2H- And cyclic monovinyl ether compounds such as sodium pyran-2-carboxylate.

（式中のＲ^４は、炭素数３〜１０のアルキル基、シクロアルキル基又はアリール基を表し、ｍは１又は２である。） The sulfur-containing hemiacetal ester derivative of the present invention can be obtained by reacting the above-mentioned sulfur-containing carboxylic acid and vinyl ether compound at a temperature in the range of room temperature to 150 ° C. At this time, an acid catalyst may be used for the purpose of promoting the reaction. Examples of such an acid catalyst include acidic phosphate compounds represented by the following general formula (4).

(In the formula, R ⁴ represents an alkyl group having 3 to 10 carbon atoms, a cycloalkyl group, or an aryl group, and m is 1 or 2.)

  Specific examples of the acidic phosphate compound represented by the general formula (4) include primary alcohols such as n-propanol, n-butanol, n-hexanol, n-octanol, and 2-ethylhexanol, and isopropanol. Examples thereof include phosphoric acid monoesters or diesters of secondary alcohols such as 2-butanol, 2-hexanol, 2-octanol, and cyclohexanol.

  In the synthesis of the sulfur-containing hemiacetal ester, an organic solvent may be used for the purpose of making the reaction system uniform and facilitating the reaction. Examples of such organic solvents include benzene, toluene, xylene, ethylbenzene, aromatic petroleum naphtha, tetralin, turpentine oil, Solvesso # 100 (trade name of Exxon Chemical Co., Ltd.), Solvesso # 150 (Exxon Chemical Co., Ltd.) Aromatic hydrocarbons such as dioxane, tetrahydrofuran, etc., methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, amyl acetate, acetic acid Esters and ether esters such as methoxybutyl and methoxypropyl acetate (PMAc), acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl amyl ketone, cyclohexanone, isophorone, mesityl oxide, methyl isoamyl ketone, ethyl n-butyl keto , Ethyl amyl ketone, diisobutyl ketone, diethyl ketone, methyl propyl ketone, diisobutyl ketone and other ketones, trimethyl phosphate, triethyl phosphate, tributyl phosphate and other phosphate esters, N, N-dimethylformamide, N, N-dimethylacetamide , N-methyl-2-pyrrolidone, N-methylmorpholine, nitrogen-containing compounds such as acetonitrile, and dimethyl sulfoxide.

  The content ratio of the component (A) and the component (B) is required to be 0.1 to 100 parts by mass of the component (B) with respect to 100 parts by mass of the component (A). Preferably it is 0.1-30 mass parts of (B) component with respect to 100 mass parts of (A) component. Less than 0.1 parts by mass is not preferable because the strength during heating is low, and more than 100 parts by mass is not preferable because the adhesive strength is lowered. If not within the above range, good adhesiveness during heating (150 to 260 ° C.) It is not possible to obtain an adhesive composition that expresses.

  Moreover, in the range which does not impair the effect of this invention, one or more other resin chosen from urethane resin other than the epoxy resin of (A) component, a polyester resin, a phenoxy resin, an acrylic resin, etc. as needed ( You may use together with A) component. The content of these other resins is preferably 50% by mass or less, more preferably 25% by mass or less, in the resin component to be used (component (A) + component (B) + other resin). is there.

  As the (A) component amine curing agent used in the present invention, known amine curing agents used as epoxy resin curing agents can be used, for example, aliphatic amines, aromatic amines, dicyandiamide, dihydrazide compounds. And more specifically, dicyandiamide, ethylenediamine, diaminopropane, diaminobutane, diethylenetriamine, and the like. These may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  The compounding amount of the component (C) is preferably 0.05 to 20 parts by mass with respect to a total of 100 parts by mass of the component (A) and the component (B) from the viewpoint of obtaining appropriate curability. Preferably it is 1-15 mass parts.

  As the (D) component imidazole curing accelerator used in the present invention, known imidazole curing accelerators used as epoxy resin curing accelerators can be used, for example, 2-methylimidazole, 2-undecyl. Provision of imidazole, 1-decyl-2-phenylimidazole, 1-cyanomethyl-2-undecylimidazole, 2,4-diamino-6- (2′-methylimidazolyl- (1 ′))-ethyl-s-triazine isocyanuric acid Products, 2-methylimidazole isocyanuric acid contributor, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo (1,2-a) benzimidazole and the like. These may be used individually by 1 type, and may be used in combination of 2 or more types.

  The blending amount of the component (D) is usually preferably 0.05 to 20 parts by mass with respect to a total of 100 parts by mass of the component (A) and the component (B) from the viewpoint of obtaining an appropriate curing acceleration effect. More preferably, it is 0.1-10 mass parts.

  The filler of the component (E) used in the present invention may be either inorganic or organic, and known fillers conventionally used for epoxy resin compositions can be used.

  Here, examples of the inorganic filler include metal powder such as silver powder, gold powder, copper powder, aluminum powder, and nickel powder, carbon powder, fused silica, crystalline silica, silicon nitride, alumina, aluminum nitride, calcium carbonate, and the like. Can be mentioned. Among these inorganic fillers, metal powder is mainly used for imparting conductivity and thermal conductivity. Silver powder is particularly preferable because it is easily available, has many types of shapes and particle sizes, has good conductivity, and does not change conductivity even when heated. For insulating applications, silica is particularly preferable from the viewpoint of availability and variety.

  Examples of the organic filler include a silicone resin, a fluororesin such as polytetrafluoroethylene, an acrylic resin such as polymethyl methacrylate, a cross-linked product of benzoguanamine, melamine, and formaldehyde.

  Furthermore, a composite material of silica and an acrylic resin, a filler obtained by combining an organic compound and an inorganic compound, such as a metal coating on the surface of an organic filler, or the like can be used.

  These fillers preferably have a content of ionic impurities such as halogen ions and alkali metal ions of 10 ppm or less. Further, the shape of the filler is not particularly limited, and for example, a flake shape, a scale shape, a dendritic shape, a spherical shape, or the like is used.

The particle size of the filler (E) is not particularly limited, but typically, those having an average particle size of 1 to 50 μm are preferably used, and those having 1 to 20 μm are more preferably used. Furthermore, in addition to the micron-order filler, nano-scale one having an average particle size of about 1 to 100 nm can be used as the filler (E). Here, the average particle diameter is a volume-based 50% integrated value (D ₅₀ ) obtained by a laser diffraction particle size distribution analyzer.

  These fillers may be surface-treated with a silane coupling agent such as alkoxysilane, acyloxysilane, silazane, organoaminosilane or the like in order to improve dispersibility and the like. These fillers may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  As for the compounding quantity of this (E) component, 1-300 mass parts is preferable with respect to a total of 100 mass parts of (A) component and (B) component.

  The reactive diluent and / or organic solvent of the component (F) used in the present invention is used for adjusting the viscosity of the resin composition, and is particularly limited as long as it is a known one used for epoxy resins. Can be used without being.

  Here, the reactive diluent in the component (F) is a reactive diluent for the epoxy resin (A), has reactivity with the ring-opening polymerization of the epoxy resin, and does not deteriorate the properties of the epoxy resin. The viscosity of the composition can be adjusted. As this reactive diluent, a known reactive diluent can be used, for example, n-butyl glycidyl ether, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, styrene oxide, phenyl glycidyl ether, cresyl glycidyl ether, p- sec-butylphenyl glycidyl ether, glycidyl methacrylate, t-butylphenyl glycidyl ether, diglycidyl ether, (poly) ethylene glycol glycidyl ether, butanediol glycidyl ether, trimethylolpropane triglycidyl ether, 1,6-hexanediol diglycidyl ether Etc. These may be used singly or in combination of two or more. Of these, butyl glycidyl ether is preferred in the present invention.

  The amount of the reactive diluent used is usually such that the viscosity at 25 ° C. of the thermosetting resin composition for semiconductor bonding of the present invention (measured using an E-type viscometer under the condition of 3 ° cone) is 20%. ˜300 Pa · s, preferably 50 to 150 Pa · s is used.

  Moreover, the organic solvent in (F) component can use a well-known organic solvent if it is used in order to adjust the viscosity of the resin mixture containing (A) component and (B) component. Examples of the organic solvent include cellosolve acetate, ethyl cellosolve, butyl cellosolve, butyl cellosolve acetate, butyl carbitol acetate, diethylene glycol dimethyl ether, diacetone alcohol, N-methyl-2-pyrrolidone (NMP), dimethylformamide, N, N-dimethyl. Examples include acetamide (DMAc), γ-butyrolactone, 1,3-dimethyl-2-imidazolidinone, 3,5-dimethyl-1-adamantanamine (DMA), and the like. These may be used singly or in combination of two or more.

  Among these, N-methyl-2-pyrrolidone (NMP), N, N-dimethylacetamide (DMAc) and 3,5-dimethyl-1-adamantanamine (DMA) are preferable in the present invention.

  As for the usage-amount of this organic solvent, 20 mass parts or less are preferable normally with respect to a total of 100 mass parts of (A) component and (B) component, More preferably, it is 10 mass parts or less. By making the usage-amount of this organic solvent 20 mass parts or less, generation | occurrence | production of the void at the time of hardening the thermosetting resin composition for semiconductor adhesion of this invention is suppressed.

  Here, either the reactive diluent of the component (F) and the organic solvent may be used, or both may be used together, and both can be used for adjusting the viscosity of the resin composition. However, if the amount of the organic solvent is increased as described above, voids may occur when it is cured, and attention should be paid to the amount of the organic solvent.

  In the thermosetting resin composition for semiconductor adhesion of the present invention, in addition to the above components, a curing accelerator, rubber or silicone generally blended in this type of composition as long as the effects of the present invention are not impaired. If necessary, blend low stress agents such as coupling agents, antifoaming agents, surfactants, colorants (pigments, dyes), various polymerization inhibitors, antioxidants, and other various additives. Can do. Each of these additives may be used alone or in combination of two or more.

  Such additives include silane coupling agents such as epoxy silane, mercapto silane, amino silane, alkyl silane, clade silane, vinyl silane, sulfide silane, titanate coupling agent, aluminum coupling agent, aluminum / zirconium coupling agent. Coupling agents such as carbon black, colorants such as carbon black, solid stress reducing components such as silicone oil and silicone rubber, and inorganic ion exchangers such as hydrotalcite.

  First, the thermosetting resin composition of the present invention is sufficiently mixed with the above-described components (A) to (F) and additives such as coupling agents blended as necessary according to a conventional method. Furthermore, it can prepare by performing a kneading | mixing process by a disperse, a kneader, a 3 roll mill, etc., and then defoaming.

  The thermosetting resin composition for semiconductor bonding of the present invention is excellent in adhesiveness, and by using this, it is possible to obtain a semiconductor device having particularly improved solder crack resistance compared to the conventional one.

  The thermosetting resin composition for semiconductor bonding of the present invention thus produced can be cured by heating at about 80 to 250 ° C. for about 0.1 to 3 hours.

Next, the semiconductor device of the present invention will be described.
The semiconductor device of the present invention is a thermosetting type for bonding semiconductors by mounting a semiconductor element (chip) on a semiconductor support substrate such as a lead frame or an organic substrate via the thermosetting resin composition for bonding semiconductors of the present invention. After heat-curing the resin composition, the lead part of the lead frame and the electrode on the semiconductor element are connected by wire bonding, and then this can be manufactured by sealing with a sealing resin. .

  The semiconductor to be bonded is not particularly limited as long as it is a known semiconductor, and examples thereof include an IC (integrated circuit), an LSI (large scale integrated circuit), a transistor, a thyristor, and a diode.

  Examples of the bonding wire include a wire made of copper, gold, aluminum, gold alloy, aluminum-silicon, or the like. Moreover, the temperature at the time of hardening the thermosetting resin composition for semiconductor adhesion is 150-250 degreeC normally, and it is preferable to heat about 0.5 to 2 hours.

  FIG. 1 shows an example of the semiconductor device of the present invention obtained as described above. Between the lead frame 1 such as a copper frame and the semiconductor element 2, the thermosetting resin for semiconductor bonding of the present invention is shown. An adhesive layer 3 that is a cured product of the composition is interposed. Further, the electrode 4 on the semiconductor element 2 and the lead portion 5 of the lead frame 1 are connected by a bonding wire 6, and these are further sealed by a sealing resin 7. In addition, as thickness of the adhesive bond layer 3, about 10-30 micrometers is preferable.

  In the semiconductor device of the present invention, a semiconductor element is bonded and fixed by a thermosetting resin composition for semiconductor bonding, which has excellent adhesive strength when heated, can suppress bleeding, and has excellent adhesion, and has excellent solder crack resistance. Therefore, it has high reliability.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples. In the following examples and comparative examples, “parts” means “parts by mass”.

(Reference Example 1; Synthesis of sulfur-containing hemiacetal ester derivative 1)
In a four-necked flask equipped with a reflux condenser, a stirrer, and a thermometer, 39.6 parts by mass of thioctic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), 18.2 parts by mass of n-propyl vinyl ether (for thioctic acid, 1.1 molar equivalents), 1-buton part of 2-butanone, AP-8 (trade name; phosphoric acid catalyst, manufactured by Daihachi Chemical Industry Co., Ltd.) 0.05 part by weight. This was stirred at 85 ° C. for 3 hours.

  From the stirred reaction solution, unreacted n-propyl vinyl ether and 2-butanone were removed under reduced pressure using an evaporator (20 mmHg, 50 ° C.), and the acid value of the reaction mixture after concentration under reduced pressure was measured. It was 35 mgKOH / g, and the calculated reaction rate was 99.3%. The acid value was calculated by titration with a 0.1 mol / L potassium hydroxide / ethanol solution by potentiometric titration. From the above, sulfur-containing hemiacetal ester derivative 1 represented by the following chemical formula (5) obtained by modifying thioctic acid with n-propyl vinyl ether was obtained.

Reference Example 2: Synthesis of sulfur-containing hemiacetal ester derivative 2
In Reference Example 1, the reaction mixture was changed in the same manner except that 18.2 parts by mass of n-propyl vinyl ether was changed to 33.0 parts by mass of 2-ethylhexyl vinyl ether (1.1 molar equivalents with respect to thioctic acid). Obtained. The acid value after concentration under reduced pressure of the obtained reaction mixture was measured (the acid value was 1.40 mgKOH / g), and the calculated reaction rate was 99.1%. From the above, sulfur-containing hemiacetal ester derivative 2 represented by the following chemical formula (6) obtained by modifying thioctic acid with 2-ethylhexyl vinyl ether was obtained.

Reference Example 3 Synthesis of sulfur-containing hemiacetal ester derivative 3
In a four-necked flask equipped with a reflux condenser, a stirrer, and a thermometer, 37.3 parts by mass of dithiodipropionic acid, 34.7 parts by mass of n-propyl vinyl ether (based on the molar equivalent of the carboxyl group of dithiodipropionic acid) , 1.1 molar equivalent), 2-butanone 14.7 parts by mass, AP-8 (manufactured by Daihachi Chemical Industry Co., Ltd., trade name: phosphoric acid catalyst) 0.05 part by mass was charged. This was stirred at 85 ° C. for 3 hours. The acid value after concentration under reduced pressure of the obtained reaction mixture was measured (the acid value was 1.73 mgKOH / g), and the calculated reaction rate was 99.3%.

  Unreacted n-propyl vinyl ether and 2-butanone were removed under reduced pressure using an evaporator (20 mmHg, 50 ° C.), and the oxidation of the reaction mixture after concentration under reduced pressure was measured to be 10.42 mg KOH / g. From the above, sulfur-containing hemiacetal ester derivative 3 represented by the following chemical formula (7) obtained by modifying dithiodipropionic acid with n-propyl vinyl ether was obtained.

Example 1
Each component was blended so as to have a blending ratio shown in Table 1, mixed, and then kneaded with a roll to produce adhesive compositions of Examples and Comparative Examples. In addition, the detail of the material used for manufacture of an adhesive composition is shown below.

[Epoxy resin of component (A)]
-Bisphenol F type glycidyl ether (manufactured by Japan Epoxy Resin, trade name: YL983U; epoxy equivalent 170)
Modified bisphenol A type glycidyl ether (Asahi Denka Kogyo Co., Ltd., trade name: EP-4005; epoxy equivalent 510)
[(B) component sulfur-containing hemiacetal ester derivative]
-Sulfur-containing hemiacetal ester derivatives 1 to 3 synthesized in Reference Examples 1 to 3
[Curing agent for component (C)]
Phenol novolac resin (manufactured by DIC, trade name: TD-2131; hydroxyl group equivalent 104)
・ Dicyandiamide (Nippon Carbide)

[Filler for component (D)]
Silver powder (average particle size 3 μm, particle size 0.1-30 μm, flake shape)
・ Silica powder (average particle size 3μm, maximum particle size 20μm, spherical)
[Curing agent for component (E)]
・ 2-Phenyl-4-methyl-5-hydroxymethylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name: 2P4MHZ)
[Reactive diluent of component (F)]
・ Reactive diluent (Nippon Kayaku Co., Ltd .; t-butylphenylglycidyl ether)
[Others]
・ Thioctic acid (manufactured by Tokyo Chemical Industry Co., Ltd.)
・ Alkoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KBM-403)
・ Polysulfide silane coupling agent (Daiso Co., Ltd., trade name: Cabras 4)

(Example 2)
A thermosetting resin composition for semiconductor adhesion was prepared in the same manner as in Example 1 except that the sulfur-containing hemiacetal ester derivative 1 was changed to the sulfur-containing hemiacetal ester derivative 2.

(Example 3)
A thermosetting resin composition for semiconductor adhesion was prepared in the same manner as in Example 1 except that the sulfur-containing hemiacetal ester derivative 1 was changed to the sulfur-containing hemiacetal ester derivative 3.

Example 4
A thermosetting resin composition for semiconductor bonding was prepared in the same manner as in Example 1 except that 180 parts by mass of silica powder (average particle size 3 μm, maximum particle size 20 μm, spherical shape) was used instead of silver powder.

(Example 5)
A thermosetting resin composition for semiconductor adhesion was prepared in the same manner as in Example 1 except that the blending amount of the sulfur-containing hemiacetal ester derivative 1 was 10 parts by mass.

(Comparative Example 1)
A thermosetting resin composition for semiconductor adhesion was prepared in the same manner as in Example 1 except that the sulfur-containing hemiacetal ester derivative was not blended and 2.0 parts by mass of alkoxysilane “KBM-403” was blended instead. .

(Comparative Example 2)
The thermosetting resin composition for semiconductor adhesion was the same as in Example 2 except that the sulfur-containing hemiacetal ester derivative was not blended and 5.0 parts by mass of the polysulfide-based silane coupling agent “Cabras 4” was blended instead. Was prepared.

(Comparative Example 3)
A thermosetting resin composition for semiconductor bonding was prepared in the same manner as in Example 2 except that the sulfur-containing hemiacetal ester derivative was not blended and 2.0 parts by mass of thioctic acid was blended instead.

  About the thermosetting resin composition for semiconductor adhesion obtained by the said Example and comparative example, various characteristics were evaluated by the method shown below. The results are summarized in Table 1 including the blending amount.

<Characteristic evaluation method>
(1) Initial viscosity The viscosity of the thermosetting resin composition for semiconductor bonding immediately after the preparation is measured using an E-type viscometer (3 ° cone) manufactured by Toki Sangyo Co., Ltd. at 25 ° C. and 2.5 rpm. It was measured.

(2) Pot life The obtained thermosetting resin composition for semiconductor adhesion was left in a thermostatic bath at 25 ° C., and the number of days until the viscosity increased to 1.5 times or more of the initial viscosity was examined.

(3) Bonding strength during heating The obtained thermosetting resin composition for semiconductor bonding was applied to a copper frame to a thickness of 20 μm, and a 2 mm × 2 mm semiconductor chip (silicon chip) was mounted thereon, and the temperature was 200 ° C. And cured for 60 minutes to prepare a connection sample. The connection sample was measured at 260 ° C. using a bond tester SS-100KP manufactured by Seishin Shoji Co., Ltd.

(4) Bleed property The obtained thermosetting resin composition for semiconductor bonding is applied to a copper frame to a thickness of 20 μm, and a 2 mm × 2 mm semiconductor chip (silicon chip) is mounted thereon, and then heated at 200 ° C. at 60 ° C. A connection sample was prepared by heat-curing for minutes. Thereafter, the bleed length from the end portion was measured with a digital microscope. The case where the bleed length after curing (distance from the end of the liquid resin composition to the bleed tip) was less than 5 μm was determined to be acceptable (◯), and the case where the bleed length was 5 μm or more was determined to be unacceptable (x).

(5) Solder reflow resistance The obtained thermosetting resin composition for semiconductor bonding is applied to a steel frame to a thickness of 20 μm, and a 6 mm × 6 mm semiconductor chip (silicon chip, surface aluminum wiring only) is applied thereon. After mounting and heating and curing at 200 ° C. for 60 minutes, sealing is performed using an epoxy resin sealing material (trade name: KE-G1200) manufactured by Kyocera Chemical Co., Ltd., and a semiconductor package (80 pQFP, 14 mm × 20 mm × 2 mm). For sealing, first, transfer molding was performed under the conditions of 1 MPa at 175 ° C. for 2 minutes, and then post-curing at 175 ° C. for 8 hours.

  This package is subjected to moisture absorption treatment at 85 ° C. and 85% RH for 168 hours, followed by IR reflow treatment (260 ° C., 10 seconds) to microscopically check for the occurrence of external cracks in the package (package surface cracks). (Magnification: 15 times) was observed and the number of occurrences was examined. Further, the occurrence of internal cracks (chip cracks) in the package was observed with an ultrasonic microscope, and the number of occurrences was examined (n = 5).

  As is clear from Table 1, the thermosetting resin composition for semiconductor bonding of Examples can suppress the generation of bleed and has high adhesive strength during heat. Moreover, the semiconductor device manufactured using this resin composition was excellent in solder reflow resistance.

  DESCRIPTION OF SYMBOLS 1 ... Lead frame, 2 ... Semiconductor element, 3 ... Adhesive layer, 4 ... Electrode, 5 ... Lead part, 6 ... Bonding wire, 7 ... Sealing resin

Claims (7)

(A) an epoxy resin;
(B) a sulfur-containing hemiacetal ester derivative;
(C) an amine curing agent;
(D) an imidazole curing accelerator;
(E) a filler;
(F) a reactive diluent and / or an organic solvent;
A thermosetting resin composition for semiconductor bonding, comprising: The component (B) is a sulfur-containing hemiacetal ester derivative represented by the following general formula (1a), (1b) or (1c)

(In the formula, R ¹ is a hydrogen atom or a monovalent organic group containing a sulfur atom and a carbon atom, R ² is a monovalent organic group containing a sulfur atom and a carbon atom, or R ¹ and R ² are united. And represents a heterocyclic group containing a sulfur atom and a carbon atom, R ³ represents a monovalent hydrocarbon group having 1 to 18 carbon atoms, and Ar represents a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms. And n represents a positive integer of 1 to 20.) The thermosetting resin composition for semiconductor bonding according to claim 1, wherein   The thermosetting resin composition for semiconductor bonding according to claim 1 or 2, wherein the component (B) is liquid at room temperature and has a disulfide bond.   The content of the component (A) and the component (B) is 0.1 to 100 parts by mass of the component (B) with respect to 100 parts by mass of the component (A). Item 4. The thermosetting resin composition for semiconductor adhesion according to any one of Items 1 to 3.   5. The component (C) is contained in an amount of 0.05 to 20 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). Thermosetting resin composition for semiconductor bonding.   The semiconductor according to any one of claims 1 to 5, wherein the component (E) is contained in an amount of 1 to 300 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). Thermosetting resin composition for bonding.   A semiconductor device comprising a semiconductor element bonded to a semiconductor support substrate with the thermosetting resin composition for semiconductor bonding according to claim 1.

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