JPH04366159A - Epoxy resin composition and semiconductor device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is an epoxy resin composition suitable for use as a molding material, a powder coating material, a semiconductor encapsulation material, etc., and particularly useful for semiconductor encapsulation, and a cured product thereof. The present invention relates to a semiconductor device that has been stopped.

0002

[Prior Art and Problems to be Solved by the Invention] Epoxy resin compositions containing an epoxy resin, a curing agent, and an inorganic filler, etc., generally have better moldability and adhesion than other thermosetting resin compositions. Because of its excellent properties such as physical properties, electrical properties, mechanical properties, and moisture resistance, it is widely used as various molding materials, powder coating materials, and electrical insulation materials.In recent years, it has also been used as semiconductor encapsulating materials, potting materials, and coatings. It is attracting attention as a material.

On the other hand, in the electronics industry, recently,
The external dimensions of packages are becoming smaller and thinner due to the demand for smaller and lighter electronic devices. Furthermore, in the method of attaching semiconductor components to a circuit board, surface mounting of semiconductor devices has become popular due to the higher density of components on the board and the thinner board. However, when surface mounting a semiconductor device on a circuit board, the general method is to immerse the entire semiconductor device in a solder bath or pass it through a high temperature zone where the solder is melting, but the thermal shock caused by this process causes sealing. Problems include cracks occurring in the sealing resin layer and peeling occurring at the interface between the lead frame or chip and the sealing resin. Furthermore, such cracks and peeling become more noticeable if the encapsulating resin layer of the semiconductor device absorbs moisture before receiving the thermal shock during surface mounting, but in the actual work process, the encapsulating resin layer becomes more noticeable. Moisture absorption in the sealing resin layer is unavoidable, and this poses a problem in that the reliability of semiconductor devices sealed with epoxy resin after mounting is greatly impaired.

[0004]Therefore, it is desired to develop an epoxy resin composition that has excellent crack resistance and peeling resistance and is useful for semiconductor encapsulation.

[0005] The present invention has been made in view of the above circumstances.
An object of the present invention is to provide an epoxy resin composition that has good general properties such as mechanical strength and excellent crack resistance and peeling resistance, and a semiconductor device sealed with a cured product of this epoxy resin composition.

[0006]

[Means and Effects for Solving the Problems] As a result of intensive studies to achieve the above object, the present inventor has developed an epoxy resin composition containing a curable epoxy resin and a curing agent as follows Components of ~(C), (A) a compound represented by the following formula (1), R1 aSi(
OR2) 4-a...(1) (wherein, R1
is an unsubstituted or substituted monovalent hydrocarbon group, and R2 has 1 to 1 carbon atoms.
4 represents an unsubstituted or substituted monovalent hydrocarbon group, a is 1,
2 or 3. ) (B) Amine compound (C) A partially hydrolyzed organosilicon compound obtained by mixing with water, preferably 100 parts (parts by weight,
(the same applies hereinafter)), when a semiconductor device sealed with an epoxy resin composition containing this organosilicon compound is surface mounted on a circuit board, the semiconductor device will be exposed to thermal shock. We found that the sealing resin layer is less prone to cracking or peeling even if exposed to the amine compound. If the composition has good adhesion to the lead frame, etc., and if the sealing resin has good adhesion to the lead frame, etc., even if it is subjected to thermal shock after moisture absorption, cracking or peeling will occur due to the thermal shock. This is what I learned is that it is difficult.

[0007] Note that a silane coupling agent such as γ-glycidoxypropyltrimethoxysilane or a compound of the above formula (1) may be added to the epoxy resin composition containing an inorganic filler to improve adhesion. is publicly known. However, even if the silane coupling agent is simply blended as is, it is difficult to provide adhesive strength that can withstand cracking and peeling due to thermal shock after moisture absorption. However, it has been discovered that by blending the above partially hydrolyzed organosilicon compound into an epoxy resin composition, the adhesion is significantly improved, and as mentioned above, it exhibits excellent crack resistance and peeling resistance. It is something that

Therefore, the present invention provides an epoxy resin composition containing a curable epoxy resin and a curing agent with the following (A) to
(C) An epoxy resin composition characterized by blending a partially hydrolyzed organosilicon compound obtained by mixing the components, (A) a compound R1 aSi(OR2) represented by the following formula (1); )4-a...(1
) (wherein R1 is an unsubstituted or substituted monovalent hydrocarbon group, R
2 represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 4 carbon atoms, and a is 1, 2 or 3. ) (B) An amine compound (C) A semiconductor device sealed with water and a cured product of this epoxy resin composition is provided.

[0009] To explain the present invention in more detail below, the curable epoxy resin constituting the composition of the present invention is
An epoxy resin having two or more epoxy groups in its molecule, this epoxy resin is not particularly limited in molecular structure, molecular weight, etc., as long as it can be cured with various curing agents as described below, and is a conventionally known epoxy resin. You can use the various ones listed below. For example, epoxy resins synthesized from epichlorohydrin and various novolac resins such as bisphenol, alicyclic epoxy resins, epoxy resins into which halogen atoms such as chlorine or bromine atoms are introduced, etc. can be used.

Among these, substituted and unsubstituted novolac type epoxy resins and bisphenol A type epoxy resins are preferably used. The above epoxy resins may be used alone or in combination of two or more.

[0011] When using the above epoxy resin,
There is no problem in using a monoepoxy compound in combination as appropriate. Examples of monoepoxy compounds include styrene oxide, cyclohexene oxide, propylene oxide, methyl glycidyl ether, ethyl glycidyl ether, phenyl glycidyl ether, allyl glycidyl ether, octylene oxide, and dodecene oxide.

[0012] As the curing agent, amine curing agents typified by diaminodiphenylmethane, diaminodiphenylsulfone, metaphenylene diamine, etc., acid anhydride curing agents such as phthalic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, etc. Examples include curing agents and phenol novolak curing agents having two or more hydroxyl groups in one molecule, such as phenol novolak and cresol novolak.

Furthermore, in the present invention, various curing accelerators such as imidazole or its derivatives, tertiary amine derivatives, phosphine derivatives, cycloamidine derivatives, etc. are used to accelerate the reaction between the above-mentioned curing agent and the epoxy resin. There is no problem in using them together.

[0014] The amount of the curing agent used is the amount normally used, and the amount of the curing accelerator can also be within the usual range.

[0015] In the present invention, an inorganic filler can be blended, but the type of inorganic filler used is not limited and is appropriately selected depending on the intended use of the epoxy resin composition. One or more types selected from natural silica such as crystalline silica and amorphous silica, synthetic high-purity silica, synthetic spherical silica, talc, mica, silicon nitride, boron nitride, alumina, etc. can be used.

The amount of the inorganic filler added is preferably 100 to 1000 parts, more preferably 250 to 750 parts, based on 100 parts of the total amount of the epoxy resin and curing agent. If the amount is less than 100 parts, the resulting epoxy resin composition may not provide satisfactory results in terms of physical properties such as crack resistance, while if it exceeds 1,000 parts, the fluidity will be poor and the dispersion of the inorganic filler will be poor. may be difficult.

The composition of the present invention includes the above epoxy resin,
A partially hydrolyzed organosilicon compound is blended with a curing agent. Component (A) for obtaining this organosilicon compound is represented by the following formula (1).

R1 aSi(OR2)4-a...(1
)

Here, R1 is an unsubstituted or substituted monovalent hydrocarbon group, preferably having 1 to 8 carbon atoms. Specifically, alkyl groups such as methyl group, ethyl group, propyl group, butyl group, cycloalkyl groups such as cyclohexyl group, alkenyl groups such as vinyl group and allyl group, aryl groups such as phenyl group, and aralkyl groups such as benzyl group. groups and some or all of these hydrogen atoms can be replaced with halogen atoms, cyano groups,
Examples include groups substituted with epoxy groups, glycidyloxy groups, and the like. R2 is unsubstituted or substituted 1 having 1 to 4 carbon atoms
It is a valent hydrocarbon group, specifically a methyl group, an ethyl group,
Alkyl groups such as propyl group and butyl group, alkoxy-substituted alkyl groups such as methoxymethyl group, ethoxymethyl group, methoxyethyl group, and ethoxyethyl group, alkenyl groups such as vinyl group, allyl group, isopropenyl group, isobutenyl group, etc. Can be mentioned. a is 1, 2 or 3.

Specifically, the component (A) is represented by the following formula (2
), β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane represented by the following formula (3), diethyldimethoxysilane, methyltrimethoxysilane, phenyltrimethoxysilane, Examples include methoxysilane. These can be used alone or in combination of two or more, but 50% or more of component (A) is γ-glycidoxypropyltrimethoxysilane or β-(3,4-epoxycyclohexyl). Ethyltrimethoxysilane is preferred, and γ-glycidoxypropyltrimethoxysilane is particularly preferred.

[0021]

[Chemical formula 1]

Component (B) is an amine compound, and the primary amine compound is γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and the secondary amine compound is N-β(aminoethyl)γ. -aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, benzylmethylamine, tertiary amine compounds include, for example, triethylamine, tributylamine, N',N-dimethylaniline, 1,8 -Diazabicyclo(5.4.0) undecene-7 (DBU), diazabicyclo(4.3.0) nonene-5 (DBN), etc., especially DBU, DB
N is preferred.

The amount of component (B) used is 0.001 to 0.1 part, particularly 0.005 to 0.1 part, per 100 parts of component (A).
It is preferable to set it as 02 parts. The amount of water used as component (C) is preferably 15 to 50 parts, particularly 20 to 40 parts, per 100 parts of component (A).

The partially hydrolyzed organosilicon compound used in the present invention usually contains the above components (A) to (C) in an amount of 0 to 50%.
It can be obtained by mixing and stirring at a temperature of 10 minutes to 20 hours, but it is also possible to use one that has been stirred for a longer period of time or one that has been left to stand for several days to several months instead of stirring.

The amount of the organosilicon compound thus obtained is 0.1 parts per 100 parts of the epoxy resin composition.
~1 part, particularly preferably 0.15 to 0.7 part. If the amount is less than 0.1 part, the effect may not be sufficiently exhibited, and if the amount exceeds 1 part, the stability during storage may be reduced.

[0026] The composition of the present invention can contain conventionally known stress-lowering agents, but silicone-modified phenolic resins can be used as stress-lowering agents in order to improve reliability such as moisture resistance and crack resistance. , silicone-modified epoxy resins are preferably used.

Furthermore, various additives may be added to the composition of the present invention depending on the intended use and the like, if necessary. For example, waxes, fatty acids such as stearic acid, mold release agents such as metal salts thereof, pigments such as carbon black, dyes, antioxidants, flame retardants, and other additives should not be blended in normal amounts. No problem.

[0028] The composition of the present invention can be prepared by uniformly stirring and mixing predetermined amounts of the above-mentioned components, kneading with a kneader, roll, extruder, etc. that has been heated to 70 to 95°C, cooling, and pulverizing. It can be obtained in this way. In addition,
There is no particular restriction on the order of blending the components.

In the case of sealing the semiconductor device, conventional molding methods such as transfer molding, injection molding, and casting can be used. In this case, the molding temperature of the epoxy resin is 1
It is preferable to carry out post-curing at 50 to 180°C for 2 to 16 hours at 150 to 180°C.

[0030]

[Examples] The present invention will be specifically explained below with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. Before explaining the Examples, the method for producing the organosilicon compound and silicone-modified epoxy resin used in the present invention will be explained.

[Production method of organosilicon compound] γ-glycidoxypropyltrimethoxysilane, phenyltrimethoxysilane, DBU, and water were mixed in the amounts shown in Table 1, and the mixture was stirred at 25° C. for 2 hours to partially form the organic silicon compound. Hydrolyzed organosilicon compounds (a) and (b) were obtained.

[0032]

[Table 1]

[Method for producing silicone-modified epoxy resin] Epoxidized phenol novolak resin (with a softening point of 80°C) (
A mixture of 32 g of 2-allylphenol and 1 g of tributylamine was added dropwise with stirring at a temperature of 110°C over a dropping time of 10 minutes, and stirring was continued at a temperature of 110°C for 2 hours. Unreacted 2-allylphenol and tributylamine were distilled off from the obtained contents under reduced pressure, and allyl group-containing epoxy resin (
Allyl equivalent: 1490, epoxy equivalent: 235).

Next, in a four-necked flask similar to the above, 120 g of the allyl group-containing epoxy resin obtained by the above method, 100 g of methyl isobutyl ketone, 200 g of toluene, and 2-ethylhexanol-modified chloroplatinic acid with a platinum concentration of 2% were added. Add 0.04 g of each solution, perform azeotropic dehydration for 1 hour, and prepare organopolysiloxane 8 of the following formula (4) at reflux temperature.
0 g was added dropwise over 30 minutes, and the mixture was further stirred at the same temperature for 4 hours to react.The resulting contents were washed with water and the solvent was distilled off under reduced pressure to obtain a silicone-modified epoxy resin.

[0035]

[Chemical 2]

[Examples 1, 2, 3, Comparative Examples 1, 2] An epoxidized cresol novolak resin (curable epoxy resin) with an epoxy equivalent of 200 and a phenol novolak resin with a phenol equivalent of 110, an organic resin produced by the above method. A silicon compound or untreated γ-glycidoxypropyltrimethoxysilane and a silicone-modified epoxy resin produced by the above method were used in the amounts shown in Table 2, and 10 parts of brominated epoxy novolak resin and 1 part of triphenylphosphine were used. .0 parts, 260 parts of quartz powder, 1.5 parts of wax E,
The mixture obtained by adding 1.0 part of carbon black was uniformly stirred and mixed, kneaded and cooled using a kneader roll that had been heated to 75 to 95° C. to obtain an epoxy resin composition.

The following tests (a) to (e) were conducted on these epoxy resin compositions. The results are also listed in Table 2. (a) Mechanical strength (bending strength, bending modulus) JIS
According to K-6011, a bending rod of 10 mm x 4 mm x 100 mm was molded under the conditions of 175° C., 70 kg/cm 2 , and 2 minutes of molding time, and was post-cured at 180° C. for 4 hours and then measured. (b) Glass transition temperature The value was measured using a 5 mm x 5 mm x 15 mm test piece when the temperature was raised at a rate of 5° C./min using a dilatometer. (c) A test specimen was prepared by adhering a 15 mm x 5 mm x 5 mm molded product to a 42 alloy plate with a tensile adhesive strength of 20 mm x 20 mm x 0.15 mm (the adhesive surface was 15 mm x 5 mm), Tensile adhesion was measured. Incidentally, the curing conditions were the same as in the above test (a). (d) Crack resistance during moisture absorption (when PKG cracks occur)
After gluing a silicon chip with a size of 10.0 mm x 8.0 mm x 0.3 mm to a 64PIN-QFP frame (42 alloy) and molding an epoxy resin composition on this,
The samples were left in a constant temperature and humidity bath at 85° C. and 85% RH for 12 hours, and then immersed in a solder bath at 215° C. for 30 seconds to examine the resin crack occurrence rate (number of samples n=20). Incidentally, the curing conditions were the same as in the above test (a). (e) Moisture resistance of LSI (LSI failure rate) 50 pieces of 256 kbit DRAM memory LSI were molded at 85°C.
, VPS (Vapor Phase So
lder (vapor phase solder bath)) for 60 seconds, and then left in saturated steam at 121°C and 2 atm for 200 hours.
The failure rate of the electrical operation of the LSI was measured. Incidentally, the curing conditions were the same as in the above test (a).

[0038]

[Table 2]

[0039] As shown in Table 2, the epoxy resin composition containing the partially hydrolyzed organosilicon compound obtained according to the present invention can be used in combination with a conventionally used organosilicon compound (γ-glycidoxypropyl tritributylene). methoxysilane)
Compared to the case where it is blended as is, it is recognized that it has superior properties in terms of adhesive strength, without deterioration in mechanical strength and glass transition temperature.

[0040]

[Effects of the Invention] As explained above, the epoxy resin composition of the present invention provides a cured product with excellent crack resistance and peeling resistance against thermal shock, and is suitable as a semiconductor encapsulating material. Semiconductor devices that can be used and encapsulated with the compositions of the present invention are of high quality.

Claims (2)

[Claims] Claim 1: A partially hydrolyzed organosilicon compound obtained by mixing the following components (A) to (C) into an epoxy resin composition containing a curable epoxy resin and a curing agent. An epoxy resin composition characterized by: (A) Compound R1 aSi(OR2)4-a...(1) represented by the following formula (1)
) (wherein R1 is an unsubstituted or substituted monovalent hydrocarbon group, R
2 represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 4 carbon atoms, and a is 1, 2 or 3. ) (B) Amine compound (C) Water 2. A semiconductor device sealed with a cured product of the epoxy resin composition according to claim 1.