JP2003342448A - Resin paste for semiconductor and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a resin paste for semiconductors which has such excellent reliability that a decrease in hot bonding strength does not occur, and the resin paste layer does not peel when subjected to a soldering crack resistance test after moisture absorption. <P>SOLUTION: The resin paste essentially consists of (A) an epoxy resin, (B) a curing agent, (C) a compound having a structure represented by formula (1) in the molecule, and (D) a filler, wherein the component C is present in an amount of 0.1-50 pts.wt. per 100 pts.wt. epoxy resin A. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin paste for adhering semiconductor elements such as IC and LSI to a metal frame, an organic substrate and the like.

[0002]

2. Description of the Related Art Conventionally, a resin paste for semiconductors has been generally used as a method for adhering a semiconductor element such as an IC to a lead frame. In response to the trend toward smaller and lighter electronic devices and higher functionality in recent years, semiconductor devices are becoming smaller, thinner, and narrower in pitch. There has been a strong demand for improvement in solder crack resistance after moisture absorption of a device. In order to improve resistance to solder cracking, it is important that the semiconductor element and the lead frame are in close contact with each other and that stress during soldering is relaxed. Among them, it was particularly important to improve the adhesion after the moisture absorption treatment, but in the conventional semiconductor resin paste, the adhesion between the lead frame or the semiconductor element and the semiconductor resin paste after the moisture absorption treatment is deteriorated, and the semiconductor There was a problem that the reliability of the device did not improve as expected.

[0003]

DISCLOSURE OF THE INVENTION The present invention is for a semiconductor having excellent reliability in which adhesion is not deteriorated by moisture absorption treatment and peeling of a resin paste layer for semiconductor does not occur in a solder crack resistance test after moisture absorption treatment. A resin paste and a semiconductor device using the same are provided.

[0004]

DISCLOSURE OF THE INVENTION The present invention comprises (A) an epoxy resin, (B) a curing agent, (C) a compound having a structure represented by the formula (1) in the molecule, and (D) a filler as essential components. And (C) the compound having the structure represented by the formula (1) in the molecule is 0.1 to 50 per 100 parts by weight of the epoxy resin.
This is a resin paste for semiconductors, which is part by weight.

[0005]

[Chemical 5]

In a further preferred embodiment, the compound (C) having the structure represented by the formula (1) in the molecule is a compound represented by the formula (2), (3) or (4). It is a paste.

[Chemical 6]

[Chemical 7]

[Chemical 8] Further, it is a semiconductor device manufactured by using the resin paste for a semiconductor described above.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The (A) epoxy resin used in the present invention is a monomer or oligomer having an epoxy group,
Refers to all polymers. For example, bisphenol A, bisphenol F, phenol novolac, polyglycidyl ether obtained by reaction of cresol novolacs with epichlorohydrin, crystalline epoxy resin such as biphenyl type epoxy resin, stilbene type epoxy resin, hydroquinone type epoxy resin, butanedioldiene Aliphatic epoxy resins such as glycidyl ether and neopentyl glycol diglycidyl ether, heterocyclic epoxy resins such as diglycidyl hydantoin, alicyclic compounds such as vinylcyclohexenedioxide, dicyclopentadienedioxide and alicyclic diepoxy adipate Epoxy resin, dicyclopentadiene modified phenol type epoxy resin, triphenol methane type epoxy resin, naphthol type epoxy resin, phenol Examples thereof include hydrogenated epoxy resins such as rutile type epoxy resin, biphenylaralkyl type epoxy resin, glycidyl amine, and 2,2-bis (4-hydroxycyclohexyl) propane diglycidyl ether. These may be used alone or in combination. Can be used. Although there are various types of epoxy resins depending on the molecular weight, those having a small molecular weight and being liquid at room temperature are preferable from the viewpoint of workability in compounding and viscosity after compounding.

When the epoxy resin is solid or semi-solid, or when it is liquid and has a high viscosity, it is preferable to use a reactive diluent having an epoxy group together. Examples of the reactive diluents include n-butyl glycidyl ether, versatic acid glycidyl ester, styrene oxide,
Examples thereof include ethylhexyl glycidyl ether, phenyl glycidyl ether, cresyl glycidyl ether, butyl phenyl glycidyl ether, and these may be used alone or in combination of two or more.

Examples of the curing agent (B) used in the present invention include dicarboxylic acid dihydrazide compounds, imidazole compounds, aliphatic amines, aromatic amines, dicyandiamide, and phenol resins. These may be used alone or in combination. It can be used together. Among these, dicarboxylic acid dihydrazide compounds, imidazole compounds, aliphatic amines, aromatic amines, and dicyandiamide have primary and secondary amines in the molecule, so the structure of formula (1) is opened during curing to improve the adhesive strength. It is preferable because

Examples of the dicarboxylic acid dihydrazide compound include carboxylic acid dihydrazides such as adipic acid dihydrazide, dodecanoic acid dihydrazide, isophthalic acid dihydrazide, p-oxybenzoic acid dihydrazide, and the like. These may be used alone or in combination. Can be used.

Examples of the imidazole compound include 2
-Methylimidazole, 2-ethylimidazole, 2-
Phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-dihydroxy methyl imidazole, 2-C ₁₁ H ₂₃ - General such as imidazole 2,4-diamino-which has been added storage stability by adding imidazole, triazine and isocyanuric acid
6- {2-methylimidazole- (1)}-ethyl-S
-Triazine, its isocyanate adduct, etc. are mentioned, and these can be used alone or in combination of two or more.

The phenol resin preferably has two or more active hydrogen groups per molecule which react with the epoxy groups and participate in crosslinking. Examples of such a phenol resin include bisphenol A, bisphenol F,
Bisphenol S, tetramethylbisphenol A, tetramethylbisphenol F, tetramethylbisphenol S, dihydroxydiphenyl ether, dihydroxybenzophenone, o-hydroxyphenol, m-hydroxyphenol, p-hydroxyphenol, biphenol, tetramethylbiphenol, ethylidene bisphenol, methylethylidene Phenol novolac resins and monohydric phenols obtained by reacting bis (methylphenol), cyclohexylidene bisphenol, monohydric phenols such as phenol, cresol and xylenol with formaldehyde in dilute aqueous solution under strong acidity Initial condensation products with polyfunctional aldehydes such as acrolein and glyoxal under acidic conditions, resorcin, catechol, hydroquino Initial condensate and the like of the acidic conditions of polyhydric phenols with formaldehyde etc., these can be used in combination of one or more. The compounding amount of the (B) curing agent is not particularly limited, but is preferably 0.1 to 200 parts by weight per 100 parts by weight of the epoxy resin. If it is less than 0.1 parts by weight, the adhesive strength may be lowered, and if it is more than 200 parts by weight, the viscosity may be increased and the workability may be lowered, which is not preferable.

Specific examples of the compound having the structure represented by the formula (1) in the molecule (C) used in the present invention are represented by the formulas (2), (3) and (4), but are not limited thereto. However, these may be used alone or in combination of two or more. Among them, at least one selected from the compounds represented by the formulas (2), (3) and (4) is particularly preferable.

By having the structure (dithiocarbonate group) represented by the formula (1) in the molecule, the ring is opened at the time of curing and the interaction such as hydrogen bond with the adherend becomes strong, so that the adhesive strength is increased. Further, the thiol is produced by the improvement and the ring opening, and the curing rate is improved because the thiol and the epoxy group react with each other. A reaction example of the structure represented by the formula (1) and an amine is shown in the formula (5).

[Chemical 9] The compounding amount of the compound having the structure represented by formula (1) in the molecule (C) is preferably 0.1 to 50 parts by weight, and more preferably 0.3 to 100 parts by weight of the epoxy resin.
~ 20 parts by weight. If it is less than the lower limit, the formula (1)
There is no effect of preventing a decrease in adhesive strength after moisture absorption by compounding a compound having a structure represented by
When the amount exceeds the upper limit, the adhesive strength after moisture absorption is not significantly reduced, but the viscosity is increased, which is not preferable.

Examples of the (D) filler used in the present invention include inorganic fillers and organic fillers. Examples of the inorganic filler include metal powder such as gold powder, silver powder, copper powder, and aluminum powder, fused silica, crystalline silica, silicon nitride, alumina, aluminum nitride, talc, and the like. Among these, the metal powder is mainly used for imparting electrical conductivity and thermal conductivity. As an organic filler,
Examples thereof include silicone resins, fluororesins such as polytetrafluoroethylene, acrylic resins such as polymethylmethacrylate, and crosslinked products of benzoguanamine or melamine with formaldehyde. These fillers preferably have a content of ionic impurities such as halogen ions and alkali metal ions of 10 ppm or less.

As the shape of the filler, for example, a flake shape, a scale shape, a resin shape, a spherical shape, or the like is used. Although the particle size of the filler used varies depending on the viscosity of the required resin paste for semiconductors, the average particle size is usually 0.3.
It is preferable that the maximum particle size is about 20 μm and the maximum particle size is about 50 μm. If the average particle size is less than 0.3 μm, the viscosity becomes high, and 2
If it exceeds 0 μm, bleeding may occur because the resin component flows out during coating or curing. Maximum particle size is 50
When it exceeds μm, when the resin paste for semiconductor is applied by the dispenser, the outlet of the needle is blocked, and continuous use for a long time cannot be performed. Further, a relatively coarse filler and a fine filler may be mixed and used, and various types and shapes may be appropriately mixed. Further, in order to impart required characteristics, a filler other than the above may be used. For example, a nanoscale filler having a particle size of about 1 to 100 nm, a composite material of silica and acrylic, a composite filler of an organic compound and an inorganic compound such as a material obtained by applying a metal coating to the surface of an organic filler, and the like can be mentioned. . The filler of the present invention may be one whose surface is previously treated with a silane coupling agent such as alkoxysilane, acyloxysilane, silazane or organoaminosilane. The compounding amount of the (D) filler is not particularly limited, but is 1.0 to 9 per 100 parts by weight of the resin paste.
5 parts by weight is preferred. If it is less than 1.0 part by weight, the viscosity may be too low to cause sagging of the paste, or the reinforcing strength due to the filler may not be obtained, resulting in a decrease in adhesive strength and solder resistance. When the viscosity is high, the workability is lowered, and the paste hardened product becomes brittle, so that the solder resistance may be lowered, which is not preferable.

The resin paste for semiconductors of the present invention is (A)-
The component (D) is an essential component, but in addition to these, a curing accelerator, a silane coupling agent, a titanate coupling agent, a pigment, a dye, a defoaming agent, a surfactant, an ion scavenger, a solvent, if necessary. Additives such as can be appropriately blended. The resin paste for a semiconductor of the present invention is (A) to (D).
It can be obtained by a manufacturing method in which components, other additives and the like are premixed, kneaded by using a roll or the like, and then defoamed under vacuum. A known method can be used to manufacture a semiconductor device using the resin paste for a semiconductor of the present invention.

[0018]

EXAMPLES The present invention will be specifically described with reference to Examples. The mixing ratio of each component is parts by weight. <Examples 1 to 15> Each component was kneaded with a roll according to the formulation in Table 1 and defoamed using a vacuum chamber to obtain a resin paste for semiconductors. The obtained resin paste for semiconductors was evaluated by the following methods. The results are shown in Table 1.

<Raw material components used> Epoxy resin: Bisphenol A type epoxy resin (viscosity 4000 mPas
・ S / 25 ° C, epoxy equivalent 170) (hereinafter BPAE
P) 2,2-bis (4-hydroxycyclohexyl) propane diglycidyl ether (viscosity 1700 mPa · s / 2
5 ° C., epoxy equivalent 190) (hereinafter referred to as HBPADGE) Curing agent: dicyandiamide 2-phenyl-4-methyl-imidazole (hereinafter 2P
4MZ) Compound having the structure of formula (1) in the molecule: compound represented by formula (2)

[Chemical 10]

A compound represented by the formula (3), wherein m is 4 as an average value and n is 12 as an average value.

[Chemical 11] It is shown by the formula (4), m is 3 as an average value, and n is 10 as an average value.
Compound of

[Chemical 12]

Inorganic filler: Silver powder: Particle size 0.1 to 50 μm, average particle size 3 μm, flake shape. Silica: average particle size 3 μm, maximum particle size 20 μm, spherical.

<Evaluation Method> Viscosity: Using an E-type viscometer (3 ° cone), 25 ° C,
The value at 2.5 rpm was measured. -Adhesive strength: A 5 mm x 5 mm silicon chip was mounted on a copper frame using a resin paste for semiconductors, and cured at 200 ° C for 60 minutes using an oven. After curing, the die shear strength during heating at 260 ° C. was measured. -Adhesive strength after moisture absorption treatment: A sample was prepared in the same manner as the adhesive strength, and the sample was allowed to stand for 72 hours in an environment of 85 ° C and relative humidity of 85% for moisture absorption treatment. 260 after moisture absorption
The die shear strength during heating at ℃ was measured. -Soldering resistance (peeling rate): Silicon chip (size 9.0)
(mm × 9.0 mm) was mounted on a lead frame (made of copper) using a resin paste for semiconductors, and cured at 200 ° C. for 60 minutes under an atmosphere of nitrogen in an oven. An 80-pin QFP (package size 14 × 20 mm, thickness 2.
0 mm), the mold temperature is 175 ° C., the injection pressure is 7.5 MPa,
Transfer molding with a curing time of 60 seconds, 175 ° C,
It was post-cured in 8 hours. The obtained package is 85 ℃,
Leave for 168 hours in an environment of 85% relative humidity, then 2
It was immersed in a solder bath at 60 ° C. for 10 seconds. The total value of the peeling area inside the package was measured using a transmission type ultrasonic flaw detector, and the peeling area between the chip and the epoxy resin encapsulant and the lead frame and epoxy were measured using a reflection type ultrasonic flaw detector. The total value of the peeled area from the resin sealing material was measured.
(Peeling area of die attach layer) = [(total value of peeling area in transmission)-(total value of peeling area in reflection)]
The peeling rate of the resin paste for a semiconductor is calculated as (peeling rate) = [(peeling area of die attach layer) / (chip area) × 100].
The average value of 5 packages was calculated and expressed as%.

<Comparative Examples 1 to 14> According to the formulations shown in Table 2, resin pastes for semiconductors were obtained in the same manner as in Examples and evaluated in the same manner as in Examples. The results are shown in Table 2.

[Table 1]

[0024]

[Table 2]

According to the present invention, there is no reduction in adhesive strength under heat, and a highly reliable resin paste for semiconductors in which peeling of the resin paste layer for semiconductors does not occur in the solder crack resistance test after moisture absorption treatment, and A semiconductor device using this is obtained.

Continued front page    F term (reference) 4J002 BD154 BG064 BG073 CC032                       CC042 CC062 CC184 CC194                       CD011 CD021 CD041 CD051                       CD061 CD071 CD131 CP034                       DA078 DA098 DE148 DF018                       DJ008 DJ018 DJ048 ED056                       EE036 EJ026 EJ036 EN016                       EN056 EQ026 ET006 EU116                       EV076 EV317 FD142 FD146                       GJ01 GQ05                 4J036 AB01 AB15 AC02 AC05 AD07                       AD08 AD10 AE05 AE07 AF05                       AF06 AF08 AH00 AJ09 DB05                       DC06 DC10 DC31 DC35 DC40                       DD01 FA02 FA03 FA04 FA05                       FA12 FB02 FB03 FB08 FB09                       FB16 JA06 JA15

Claims (4)

[Claims] 1. An epoxy resin (A), a curing agent (B),
(C) A compound having a structure represented by the formula (1) in the molecule, and (D) a filler as an essential component, and a compound having a structure represented by the formula (1) in the (C) molecule is 100% by weight of an epoxy resin. Resin paste for semiconductor, characterized in that it is 0.1 to 50 parts by weight per part. [Chemical 1] 2. The semiconductor according to claim 1, wherein the compound (C) having a structure represented by formula (1) in the molecule is a compound represented by formula (2), (3) or formula (4). Resin paste. [Chemical 2] [Chemical 3] [Chemical 4] 3. The semiconductor according to claim 1, wherein (B) the curing agent contains at least one of a dicarboxylic acid dihydrazide compound, an imidazole compound, an aliphatic amine, an aromatic amine and dicyandiamide. Resin paste 4. A semiconductor device manufactured by using the resin paste for semiconductor according to claim 1. Description: