JP6758051B2 - Liquid epoxy resin compositions, semiconductor encapsulants, and semiconductor devices - Google Patents

Description

The present invention relates to a liquid epoxy resin composition, a semiconductor encapsulant, and a semiconductor device, and more particularly to a liquid epoxy resin composition excellent in creeping suppression, a semiconductor encapsulant using this liquid epoxy resin composition, and a semiconductor device. ..

Currently, in semiconductor devices, lead-free solder is mainly used for joining the electrodes of semiconductor chips and the wiring of a substrate. Here, the semiconductor chip is sealed with a semiconductor encapsulant containing an epoxy resin as a main component in order to maintain reliability and the like.

Conventionally, phenolic compounds have been mainly used as curing agents for epoxy resin compositions. However, lead-free solders currently used for bonding semiconductor devices are characterized by having a high melting point, being hard, and having high toughness. In order to make the epoxy resin composition compatible with lead-free solder having these characteristics, it is necessary to increase the glass transition point (Tg), and it is difficult to make it compatible with a phenolic curing agent.

As a method for increasing the Tg of the epoxy resin composition, it is conceivable to use an amine-based curing agent. However, although the amine-based curing agent is excellent in moisture resistance and thermal cycle resistance, the curing speed is slow. Therefore, after applying the amine-based curing agent to the semiconductor chip as a semiconductor encapsulant, before the epoxy resin composition is cured, it is placed on the semiconductor chip. There is a problem that the phenomenon of creeping in which the epoxy resin creeps up is likely to occur.

FIG. 1 shows a schematic diagram for explaining the occurrence of creeping. In the left figure of FIG. 1, the substrate and the Si die, which is a semiconductor chip, are connected by bumps. In the left figure of FIG. 1, the substrate and the Si die are plasma-treated in order to improve the wettability of the semiconductor encapsulant. In the central view of FIG. 1, an underfill agent (CUF), which is a kind of semiconductor encapsulant, is dispensed around the Si die, and the underfill agent penetrates between the substrate and the Si die by surface tension or the like. After that, as shown in the right figure of FIG. 1, when the underfill agent is heat-cured, creeping occurs in which the underfill agent creeps up on the upper part of the Si die.

The present inventors have studied the addition of dimethylpolysiloxane to the epoxy resin composition in order to suppress creeping of the epoxy resin composition containing an amine-based curing agent. Here, as the addition of dimethylpolysiloxane to the epoxy resin, a blend obtained by preheating and melting 100 parts by weight or less of a predetermined silicone polymer with respect to 100 parts by weight of the phenol resin is added to 100 parts by weight of the epoxy resin. A method for producing an epoxy resin molding material, which comprises blending silicone polymers 4 to 30 and melt-kneading, has been reported (Patent Document 1).

Japanese Unexamined Patent Publication No. 05-194714

However, since the manufacturing method of the epoxy resin molding material uses a phenol resin, there is a problem that the Tg of the epoxy resin is low and it is difficult to use it in a semiconductor device using lead-free solder as described above. ..

An object of the present invention is to provide a liquid epoxy resin composition capable of increasing the Tg of an epoxy resin, using an amine-based curing agent having excellent moisture resistance and thermal cycle resistance, and suppressing creeping. To do.

The present invention relates to a liquid epoxy resin composition, a semiconductor encapsulant, and a semiconductor device that solve the above problems by having the following configurations.
[1] (A) epoxy resin, (B) amine-based curing agent, and (C) general formula (1):

Includes dimethylpolysiloxane represented by (in the formula, n is 1 to 200) or dimethylpolysiloxane represented by the general formula (1) modified with epoxy .
A liquid epoxy resin composition, wherein the component (C) is 0.01 to 0.30 parts by mass with respect to a total of 100 parts by mass of the components (A) and (B).

According to the present invention [1], it is possible to provide a liquid epoxy resin composition that can use an amine-based curing agent and suppress creeping.

According to the present invention [5], it is possible to obtain a semiconductor encapsulant using a liquid epoxy resin composition that can suppress creeping while using an amine-based curing agent. According to the present invention [6], a highly reliable semiconductor device can be obtained by using a liquid epoxy resin composition that uses an amine-based curing agent and can suppress creeping.

It is a schematic diagram for demonstrating the occurrence of creeping.

The liquid epoxy resin composition of the present invention (hereinafter referred to as a resin composition) comprises (A) an epoxy resin, (B) an amine-based curing agent, and (C) a general formula (1):

Contains dimethylpolysiloxane represented by (in the formula, n is 1 to 200).
The component (C) is 0.01 to 0.30 parts by mass with respect to a total of 100 parts by mass of the component (A) and the component (B).

The component (A) imparts adhesiveness and curability to the resin composition, and imparts durability and heat resistance to the cured resin composition. As the component (A), liquid bisphenol A type epoxy resin, liquid bisphenol F type epoxy resin, liquid naphthalene type epoxy resin, liquid aminophenol type epoxy resin, liquid hydrogenated bisphenol type epoxy resin, liquid alicyclic epoxy resin, liquid Examples thereof include alcohol ether type epoxy resin, liquid cyclic aliphatic type epoxy resin, liquid fluorene type epoxy resin, liquid siloxane type epoxy resin, liquid bisphenol A type epoxy resin, liquid bisphenol F type epoxy resin, liquid naphthalene type epoxy resin, and the like. A liquid aminophenol type epoxy resin is preferable from the viewpoint of adhesiveness, curability, durability and heat resistance. The epoxy equivalent is preferably 80 to 250 g / eq from the viewpoint of viscosity adjustment. Commercially available products include Nippon Steel Chemical's bisphenol F type epoxy resin (product name: YDF8170), DIC's bisphenol A type epoxy resin (product name: EXA-850CRP), and Nippon Steel Chemical's bisphenol F type epoxy resin (product name: YDF870GS). ), DIC naphthalene type epoxy resin (product name: HP4032D), Mitsubishi Chemical's aminophenol type epoxy resin (grade: JER630, JER630LSD), Momentive Performance's siloxane-based epoxy resin (product name: TSL9906), Nippon Steel Chemical Co., Ltd. Examples thereof include 1,4-cyclohexanedimethanol diglycidyl ether (trade name: ZX1658GS) manufactured by Japan, Ltd. The component (A) may be used alone or in combination of two or more.

The amine-based curing agent as the component (B) is not particularly limited as long as it has one or more active hydrogens in the molecule capable of addition reaction with the epoxy group. Examples of the amine compound include diethyltoluenediamine, dimethylthiotoludiamine, 4,4'-diamino-3,3'-dimethyldiphenylmethane, diethylenetriamine, triethylenetetramine, n-propylamine, 2-hydroxyethylaminopropylamine and cyclohexylamine. , 4,4'-Diamino-dicyclohexylmethane and other aliphatic amine compounds; 4,4'-diaminodiphenylmethane, 2-methylaniline and other aromatic amine compounds; imidazole, 2-methylimidazole, 2-ethylimidazole, 2- Imidazole compounds such as isopropyl imidazole; imidazoline compounds such as imidazoline, 2-methyl imidazoline, 2-ethyl imidazoline and the like can be mentioned. As the component (B), diethyltoluenediamine, dimethylthiotoluenediamine, and 4,4'-diamino-3,3'-dimethyldiphenylmethane are preferable from the viewpoint of reactivity and reliability.

Commercially available products of the component (B) include an amine-based curing agent manufactured by Sanyo Chemical Industries (trade name: T-12) and amine 4,4'-diamino-3,3'-dimethyldiphenylmethane manufactured by Nippon Kayaku (product name: Kayahard). AA) and the like can be mentioned. The component (B) may be used alone or in combination of two or more.

The component (C) is a general formula (1):

It is a dimethylpolysiloxane represented by (in the formula, n is 1 to 200) and suppresses creeping of the resin composition. The component (C) may be a dimethylpolysiloxane represented by the general formula (1) modified with an epoxy. Examples of commercially available products of the component (C) include dimethyl silicone oil manufactured by Shin-Etsu Silicone (product name: KF69). Examples of commercially available products obtained by modifying dimethylpolysiloxane with epoxy include epoxy-modified silicone oil (product name: SF8421) manufactured by Toray Dau Silicone.

From the viewpoint of good reactivity and reliability, the component (A) is preferably 60 to 90 parts by mass, preferably 65 to 80 parts by mass, based on 100 parts by mass of the total of the component (A) and the component (B). It is more preferably by mass.

From the viewpoint of good reactivity and reliability, the component (B) is preferably 10 to 40 parts by mass with respect to the total of the component (A) and the component (B): 100 parts by mass, and is preferably 20 to 35 parts by mass. It is more preferably by mass.

From the viewpoint of suppressing creeping, the component (C) is the total of the component (A) and the component (B): 100 parts by mass, and the component (C) is 0.01 to 0.30 parts by mass. , 0.02 to 0.10 parts by mass, more preferably.

Further, as for the component (C), the component (C) is 0.01 to 0.30 parts by mass with respect to a total of 100 parts by mass of the component (A) and the component (B), and 0.02 to 0. It is more preferably 10 parts by mass. Here, since the mass loss of the resin composition during curing is as small as about 1 to 2% by mass, the content of the preferable component (C) in the cured product is the same as the content in the resin composition. is there. Here, the quantitative analysis of the component (C) is performed by mass spectrometry.

The resin composition preferably further contains (D) rubber particles. The component (D) imparts elasticity to the resin composition. The rubber particles are not particularly limited, but silicone rubber, butadiene rubber, styrene-butadiene rubber, and methyl methacrylate-butadiene-styrene are preferable. Examples of commercially available products of the component (D) include a liquid masterbatch manufactured by Kaneka (product name: Kaneka MX-965, a bisphenol F type epoxy resin in which 25% by mass of core-shell rubber is single-dispersed) and the like.

The resin composition preferably further to include (E) charging Hamazai. The coefficient of linear expansion of the resin composition can be controlled by the component (E). Examples of the component (E) include silica fillers such as colloidal silica, hydrophobic silica, fine silica, and nanosilica, acrylic beads, glass beads, urethane beads, bentonite, acetylene black, and Ketjen black. The average particle size of the component (E) (or the average maximum diameter if it is not granular) is not particularly limited, but it is 0.05 to 50 μm so that the filler is uniformly dispersed in the resin composition. In addition, it is preferable because the resin composition is excellent in injectability when used as a semiconductor encapsulant. If it is less than 0.01 μm, the viscosity of the resin composition may increase and the injectability may deteriorate when used as a semiconductor encapsulant. If it exceeds 50 μm, it may be difficult to uniformly disperse the filler in the resin composition. The average particle size of the component (E) is more preferably 0.1 to 30 μm. As a commercially available product, Admatex high-purity synthetic spherical silica (product name: SO-E5, average particle size: 2 μm; product name: SO-E2, average particle size: 0.6 μm; SE2200-SEE, average particle size: 0. 6 μm), Denka silica (product name: FB7SDX, average particle size: 7 μm), Ryumori silica (product name: MSV-25G, average particle size: 29 μm) and the like. Here, the average particle size of the filler is measured by a dynamic light scattering type nanotrack particle size analyzer. The component (E) may be used alone or in combination of two or more.

It is preferable that the resin composition further contains a silane coupling agent which is the component (F) from the viewpoint of adhesion, and the component (F) includes 3-glycidoxypropyltrimethoxysilane and 3-aminopropyltri. Methoxysilane, vinyltrimethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, Examples thereof include bis (triethoxysilylpropyl) tetrasulfide and 3-isocyanuspropyltriethoxysilane, and 3-glycidoxypropyltrimethoxysilane and 3-aminopropyltrimethoxysilane are preferable from the viewpoint of adhesion. Examples of commercially available products include silane coupling agents manufactured by Shin-Etsu Chemical Co., Ltd. (product names: KBM403, KBE903, KBE9103) and the like. The component (F) may be used alone or in combination of two or more.

From the viewpoint of imparting appropriate elasticity to the resin composition, the component (D) is preferably 0.5 to 25 parts by mass with respect to the total of the components (A) and (B): 100 parts by mass. , 1 to 20 parts by mass, more preferably.

From the viewpoint of the coefficient of thermal expansion and injectability of the resin composition, the component (E) is preferably 40 to 450 parts by mass with respect to the total of the components (A) and (B): 100 parts by mass. It is more preferably 50 to 350.

Further, the component (E) is preferably 40 to 450 parts by mass, preferably 50 to 350 parts by mass, based on 100 parts by mass of the total of the components (A) and (B) after curing of the resin composition. And more preferable. Here, since the mass loss of the resin composition during curing is as small as about 1 to 2% by mass, the content of the preferable component (E) in the cured product is the same as the content in the resin composition. is there. Here, the quantitative analysis of the component (E) is performed by mass spectrometry.

The component (F) is preferably contained in an amount of 0.03 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the resin composition. When it is 0.03 part by mass or more, the adhesiveness is improved, and when it is 15 parts by mass or less, foaming of the resin composition is suppressed.

The resin composition of the present invention contains, if necessary, a coloring agent such as carbon black, a defoaming agent, a curing accelerator, a leveling agent, an ion trapping agent, a flame retardant, and the like, as long as the object of the present invention is not impaired. Additives and the like can be blended.

The resin composition of the present invention can be obtained, for example, by stirring, melting, mixing, and dispersing components (A) to (C) and other additives at the same time or separately, with heat treatment if necessary. Can be done. The device for mixing, stirring, dispersing, etc., is not particularly limited, but a Raikai machine equipped with a stirring and heating device, a three-roll mill, a ball mill, a planetary mixer, a bead mill, and the like can be used. .. Moreover, you may use these devices in combination as appropriate.

The resin composition of the present invention preferably has a viscosity at a temperature of 25 ° C. of 250 Pa · s or less from the viewpoint of injectability. Here, the viscosity is measured with an HB type viscometer manufactured by Brookfield.

The resin composition of the present invention is formed and applied to a desired position of an electronic component such as a substrate or an optical semiconductor by a dispenser, printing or the like. Here, when the resin composition is used as a semiconductor encapsulant, it is formed so as to fill the space between the semiconductor chip and the substrate.

The resin composition of the present invention is preferably cured at 80 to 200 ° C. for 0.2 to 6 hours.

In the resin composition of the present invention, the Tg of the epoxy resin can be increased, an amine-based curing agent having excellent moisture resistance and thermal cycle resistance can be used, and creeping can be suppressed. This resin composition is suitable as a semiconductor encapsulant. Further, a semiconductor device containing a cured product of a semiconductor encapsulant which uses an amine curing agent having a high Tg and excellent moisture resistance and thermal cycle resistance and a resin composition in which creeping is suppressed is highly reliable. Is.

The present invention will be described with reference to Examples, but the present invention is not limited thereto. In the following examples, parts and% indicate parts by mass and% by mass unless otherwise specified.

In the examples and comparative examples,
As the component (A), Nippon Steel Chemical's bisphenol F type epoxy resin (product name: YDF8170) is used.
As a component (B), Nippon Kayaku's amine 4,4'-diamino-3,3'-dimethyldiphenylmethane (product name: Kayahard AA) was used.
As the component (C), Shinetsu Silicone dimethyl silicone oil (product name: KF69) and Toray Dau Silicone epoxy-modified silicone oil (product name: SF8421) are used.
As a component (D), a liquid masterbatch made by Kaneka (product name: Kaneka MX-965, bisphenol F type epoxy resin in which 25% by mass of core-shell rubber is single-dispersed) is used.
As the component (E), a silica filler manufactured by Admatex (product name: Admafine SE2200-SEE, average particle size: 0.6 μm) is used.
used.

[Examples 2 and 4, Comparative Example 1 , Reference Examples 1 and 2 ]
After mixing the raw materials with the formulations shown in Table 1, they were dispersed at room temperature using a three-roll mill to prepare a liquid epoxy resin composition (hereinafter referred to as “resin composition”). The prepared resin compositions were all liquid.

[Evaluation of creeping]
A sample on which a Si chip having a width of 10 mm, a length of 10 mm, and a height of 0.6 mm was mounted on a printed circuit board (FR4 substrate) was prepared, and the Si chip was subjected to plasma treatment. The prepared resin composition was applied around the Si chip of the sample at room temperature using a dispenser, and then left to stand for 2 to 3 hours. The sample after standing was heated on a hot plate at 90 ° C. for 2 hours and then cured in a dryer at 150 ° C. for 2 hours. The cured sample was observed at a magnification of 5 using a metallurgical microscope, and the creeping distance was measured. When the creeping distance was less than 300 μm, it was evaluated as “◯”, and when it was 300 μm or more, it was evaluated as “x”. Table 1 shows the results.

[Evaluation of viscosity]
The viscosity of the resin composition within 24 hours after the preparation was measured using an HB type viscometer manufactured by Brookfield Co., Ltd. at a spindle: SC4-14, a rotation speed of 50 rpm, and a temperature of 25 ° C. The viscosity was “◯” when it was 250 Pa · s or less, and “x” when it exceeded 250 Pa · s. Is preferable. Table 1 shows the results.

As can be seen from Table 1, the results of creeping and viscosity were ◯ in all of Examples 2 and 4. On the other hand, in Comparative Example 1 containing no component (C), the creeping result was x.

As described above, the liquid epoxy resin composition of the present invention can increase the Tg of the epoxy resin, use an amine-based curing agent having excellent moisture resistance and thermal cycle resistance, and suppress creeping.

Claims (6)

(A) Epoxy resin, (B) Amine-based curing agent, and (C) General formula (1):
Includes epoxy-modified dimethylpolysiloxane represented by (in the formula, n is 1 to 200).
A liquid epoxy resin composition, wherein the component (C) is 0.01 to 0.30 parts by mass with respect to a total of 100 parts by mass of the components (A) and (B). (D) The liquid epoxy resin composition according to claim 1, which contains rubber particles. (E) The liquid epoxy resin composition according to claim 1 or 2, which comprises an inorganic filler. (F) The liquid epoxy resin composition according to any one of claims 1 to 3, which contains a silane coupling agent. A semiconductor encapsulant using the liquid epoxy resin composition according to any one of claims 1 to 4. A semiconductor device having a cured product of the semiconductor encapsulant according to claim 5.