JP2001002894A - Epoxy resin composition for semiconductor encapsulation and semiconductor device using the same - Google Patents

Abstract

(57) [Summary] [PROBLEMS] Even in a semiconductor device having excellent laser mark properties and electric characteristics, a leak or short circuit due to a conductive substance does not occur even in a semiconductor device having a short distance between pads and wires, and a moldability and reflow resistance. And a semiconductor device using the same. SOLUTION: (A) an epoxy resin, (B) a curing agent,
(C) a curing accelerator, (D) a phthalocyanine compound,
(E) An epoxy resin composition for semiconductor encapsulation containing an inorganic filler as an essential component, and a resin-encapsulated semiconductor device obtained by encapsulating a semiconductor element with the epoxy resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition for semiconductor encapsulation having excellent laser mark properties, electrical properties, moldability and reliability, and a semiconductor device using the same.

[0002]

2. Description of the Related Art All semiconductor devices (diodes, transistors, ICs, LSIs, etc.) sealed with resin are marked with characteristics, model numbers, and the like. Heretofore, this marking has been performed by printing using a thermosetting or ultraviolet curable ink. In recent years, a laser method that can rationalize productivity rather than the printing method is becoming mainstream.
The laser printing mechanism irradiates characters, symbols, and the like in a pattern onto the surface of the resin-encapsulated semiconductor device, and the irradiated portion is locally scorched or sublimated to roughen the surface, thereby rendering the characters or symbols. Is to be printed. The time required for marking by the laser method is several seconds or less, which is much shorter than the minute order of the printing method using ink. This laser method uses a carbon dioxide laser or YA
It is roughly divided into those using G laser. In order to obtain a clear contrast in marking with these lasers, in the epoxy resin composition for encapsulation, a combination of carbon black and an azo-based organic dye as a colorant (Japanese Patent Laid-Open No. 11-6 / 1999).
0904) and investigations involving the use of near-infrared absorbers (Section 63-1)
79921), but there are problems such as a decrease in moisture resistance, moldability, and color tone.

[0003] In addition, the surface mounting method, which enables high-density mounting in response to the miniaturization and thinning of electronic equipment, has rapidly spread in place of the pin insertion type. As a result, when the semiconductor device is mounted on the substrate, the semiconductor device itself is exposed to a high-temperature atmosphere such as a solder bath or a reflow bath at 200 ° C. or higher in a short time. At this time, the moisture contained in the sealing material is vaporized, and the generated vapor pressure acts as a peeling stress at an interface between the sealing material and an insert such as an element and a lead frame, and a gap between the sealing material and the insert is generated. In particular, in a thin semiconductor device, the semiconductor device may be blistered or cracked, which is a problem. This phenomenon is called a reflow crack, and is the most important problem of the surface mount type semiconductor device.

[0004] Further, as for semiconductor chips such as LSIs, as the degree of integration of the chips is improved, the chip size, the size and thickness of the semiconductor device, and the number of pins are increasing. Along with this, distances between pitches such as between inner leads, between pads, and between wires have become narrower. At this time, if a conductive substance such as carbon black contained in the sealing material is present as large coarse particles, conductive carbon black is sandwiched between inner leads and between pads and wires,
This is a problem that leads to poor electrical characteristics.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and has been made in view of the above. The present invention has an excellent laser mark property and electric characteristics, and has a leak caused by a conductive substance even in a semiconductor device having a short distance between pads and wires. Alternatively, it is an object of the present invention to provide a sealing material which does not cause short circuit failure and has excellent reliability such as moldability and reflow resistance, and a semiconductor device using the same.

[0006]

The present invention relates to the following. (1) An epoxy resin composition for semiconductor encapsulation comprising (A) an epoxy resin, (B) a curing agent, (C) a curing accelerator, (D) a phthalocyanine compound, and (E) an inorganic filler as essential components. object. (2) The epoxy resin composition for semiconductor encapsulation according to (1), wherein the phthalocyanine-based compound has V or VO as a central metal. (3) The epoxy resin composition for semiconductor encapsulation according to (1) or (2), wherein the epoxy resin has a melt viscosity at 150 ° C. of 0.5 Poise or less. (4) The epoxy resin for semiconductor encapsulation according to any one of (1) to (3), wherein the content of the phthalocyanine-based compound is 0.05 to 15% by weight based on the total amount of the epoxy resin and the curing agent. Composition. (5) The epoxy resin composition for semiconductor encapsulation according to any one of (1) to (4), which contains 75 to 97% by weight of an inorganic filler. (6) A resin-encapsulated semiconductor device obtained by encapsulating a semiconductor element using the epoxy resin composition for encapsulating a semiconductor according to any one of (1) to (5).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy resin (A) of the present invention comprises:
There is no particular limitation, and an epoxy resin generally used for an epoxy resin molding material for sealing can be used. For example, phenols such as phenol novolak type epoxy resin and orthocresol novolak type epoxy resin, phenols such as cresol, xylenol, resorcin, catechol, bisphenol A, bisphenol F and / or α-naphthol and β-naphthol Epoxidized novolak resin obtained by condensing or co-condensing naphthols such as dihydroxynaphthalene and aldehydes such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde and salicylaldehyde under an acidic catalyst, bisphenol A, bisphenol AD Of bisphenol F, bisphenol S, diglycidyl ethers such as alkyl-substituted or unsubstituted biphenols, and phenol-aralkyl resins Epoxidized adducts or polyadducts of phenols with dicyclopentadiene or terpenes; glycidyl ester type epoxy resins obtained by the reaction of epichlorohydrin with polybasic acids such as phthalic acid and dimer acid; diamino Diphenylmethane, glycidylamine type epoxy resin obtained by reaction of polyamine such as isocyanuric acid and epichlorohydrin, linear aliphatic epoxy resin obtained by oxidizing olefin bond with peracid such as peracetic acid, and alicyclic epoxy resin And any of these may be used in combination.

[0008] The purity of the epoxy resin (A),
In particular, the amount of hydrolyzable chlorine is preferably small because it is related to the corrosion of aluminum wiring on elements such as ICs.
It is preferably at most ppm. Here, the amount of hydrolyzable chlorine means that 1 g of a sample epoxy resin is 30 m in dioxane.
, 1 ml of 1N-KOH methanol solution, 5 minutes of reflux, and the value obtained by potentiometric titration was used as a scale.

Above all, as the epoxy resin (A) of the present invention, those which can be filled with a filler are preferable from the viewpoint of improving the heat resistance of solder, and the melt viscosity at 150 ° C. is 0.1.
Those having 5 poise or less can be suitably used. 150 ° C
Those having a melt viscosity of 0.1 poise or more are preferred. If you show something like this

Embedded image (Wherein, R 1, R 2, R 3 and R 4 are each independently hydrogen, an alkyl group (preferably having 1 to 5 carbon atoms), an alkoxyalkyl group (preferably having 2 to 5 carbon atoms) or Dialkylaminoalkyl group (C3
~ 6 are preferred))

Embedded image (Wherein, R1, R2, R3 and R4 are each independently hydrogen or an alkyl group (preferably having 1 to 5 carbon atoms);
An alkoxyalkyl group (preferably having 2 to 5 carbon atoms) or a dialkylaminoalkyl group (having 3 to 6 carbon atoms)
Is preferred))

Embedded image (Wherein, R 1, R 2, R 3 and R 4 are each independently hydrogen or an alkyl group (preferably having 1 to 5 carbon atoms);
An alkoxyalkyl group (preferably having 2 to 5 carbon atoms) or a dialkylaminoalkyl group (having 3 to 6 carbon atoms)
Are preferred)).

The curing agent is not particularly limited. For example, the curing agent is generally used in an epoxy resin molding material for encapsulating electronic parts, and includes phenols such as phenol, cresol, resorcin, catechol, bisphenol A, bisphenol F, and the like. α-naphthol, β-naphthol, novolak resins obtained by condensing or co-condensing naphthols such as dihydroxynaphthalene and aldehydes such as formaldehyde under an acidic catalyst, phenol aralkyl resins, naphthol aralkyl resins, and the like. They can be used alone or in combination. Among them, a phenol-aralkyl resin is preferable from the viewpoint of improving reflow resistance. The curing agent is a reactive group with an epoxy group for one equivalent of an epoxy group of the epoxy resin, for example,
The phenolic hydroxyl group of the novolak resin is 0.5 to
It is preferable to mix so as to be 1.5 equivalents, and it is particularly preferable to mix 0.7 to 1.2 equivalents.

The curing accelerator is not particularly restricted but includes, for example, 1,8-diaza-bicyclo (5,4,0) undecene-7, 1,5-diaza-bicyclo (4,3,0) nonene, Tertiary amines such as 5,6-dibutylamino-1,8-diaza-bicyclo (5,4,0) undecene-7, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol; These derivatives, 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-
Imidazoles such as methylimidazole and derivatives thereof, organic phosphines such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine and phenylphosphine, and phosphines such as maleic anhydride, benzoquinone and diazophenylmethane. Phosphorus compound having intramolecular polarization obtained by adding a compound having a bond, tetraphenylphosphonium tetraphenylborate, triphenylphosphine tetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, N-methylmotetraphenylphosphonium -Tetraphenylborate, triphenylphosphine, adduct of triphenylphosphine and benzoquinone, addition of triparatolylphosphine and benzoquinone , 1,8 Jiazabishikuro (5,4,0) - undecene -7,2- phenyl-4-methyl - imidazole, triphenyl phosphonium - there are triphenyl borane, may be used alone or in combination. The curing accelerator is preferably used in an amount of 0.1 to 8% by weight based on the total amount of the epoxy resin and the curing agent.

As the filler, it is necessary to use an inorganic filler from the viewpoint of reducing the hygroscopicity and improving the strength. As the inorganic filler, fused silica, crystalline silica, alumina, zircon, calcium silicate, calcium carbonate,
One or more powders of silicon carbide, boron nitride, beryllia, zirconia, or the like, or spherical beads, potassium titanate, silicon carbide, silicon nitride, single crystal fibers of alumina, etc., and one or more kinds of glass fibers may be blended. it can. Further, examples of the inorganic filler having a flame-retardant effect include aluminum hydroxide, zinc borate and the like, and these can be used alone or in combination. The amount of the inorganic filler is in the range of 75 to 97% by weight based on the entire epoxy resin composition for semiconductor encapsulation in the present invention, from the viewpoints of hygroscopicity, reduction of linear expansion coefficient, strength improvement and solder heat resistance. It is preferable that it is especially in the range of 80-95 weight%. Among the above-mentioned inorganic fillers, fused silica is preferred from the viewpoint of reducing the coefficient of linear expansion, and alumina is preferred from the viewpoint of high thermal conductivity. The filler shape is spherical in terms of fluidity during molding and mold abrasion. Is preferred.

The phthalocyanine compound as the essential component (D) is represented by the general formula (4) as a representative structure.

Embedded image Four aza groups at positions 1 and 3 of four molecules of isoindole (-
N =) to form a macrocycle. Examples of the central metal M include Fe, Ni, V, VO, Cu, and Co. Among them, V and VO are preferable from the viewpoint of laser markability. R1, R2, R3 and R4 each independently represent hydrogen, a conjugated π-electron-based substituent such as a thionyl chloride group, a phenyl group or a naphthylazo group, or an alkyl group (having 1 to 1 carbon atoms).
6 is preferable), an alkoxy group (having 1 to 6 carbon atoms)
Are preferred), an alkylthio group (having 1 to 6 carbon atoms)
Are preferred), and among them, from the viewpoint of laser markability, -SO2C
1, -CH3, -CH2CH2CH2CH3 and the like are preferred. Further, the phthalocyanine compound of (D) is 800
Compounds that can absorb wavelengths in the vicinity of nm to 1200 nm are particularly preferable from the viewpoint of laser markability as compounds that absorb wavelengths in the range of 1000 nm to 1100 nm. The content of the phthalocyanine-based compound is 0.05% by weight based on the total amount of the epoxy resin (A) and the curing agent (B).
If it is less than 15%, the printability is not sufficient, and if it exceeds 15% by weight, the moldability becomes insufficient. Therefore, 0.05 to 15% by weight is preferable. More preferably, it is in the range of 3.5 to 9% by weight.

A coupling agent can be added to the epoxy resin composition for semiconductor encapsulation according to the present invention.
There is no particular limitation on the coupling agent, and a conventionally known coupling agent may be used in addition to the silane coupling agent. For example, vinyltrichlorosilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyl Trimethoxysilane, vinyltriacetoxysilane, γ-
Mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ- [bis (β-hydroxyethyl)] aminopropyltriethoxysilane, N-
β- (aminoethyl) -γ-aminopropyltrimethoxysilane, γ- (β-aminoethyl) aminopropyldimethoxymethylsilane, N- (trimethoxysilylpropyl) ethylenediamine, N- (dimethoxymethylsilylisopropyl) ethylenediamine, methyl Trimethoxysilane, methyltriethoxysilane, N-β- (N
-Vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilane, γ-anilinopropyltrimethoxysilane, vinyltrimethoxysilane, γ-
Silane coupling agents such as mercaptopropylmethyldimethoxysilane, or isopropyl triisostearoyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, isopropyl tri (N-aminoethyl-aminoethyl) titanate, tetraoctylbis (ditridecyl phosphite) ) Titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctanoyl titanate, Isopropyl dimethacryl isostearyl titanate, isopropyl tridodecyl benzene sulfonyl titanate, iso Ropi Louis isostearoyl distearate acrylic titanate, isopropyl tri (dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, can be used in combination tetraisopropyl bis (dioctyl phosphite) one or more titanate coupling agents such as titanates. The coupling agent is preferably used in an amount of 3% by weight or less based on the entire epoxy resin composition for semiconductor encapsulation in the present invention, and is preferably used in an amount of 0.1% by weight or more in order to exert its effect. .

Further, a release agent can be added to the epoxy resin composition for semiconductor encapsulation according to the present invention. Although there is no particular limitation on the release agent, a higher fatty acid such as carnauba wax and a polyethylene wax can be used alone or in combination. The release agent is preferably used in an amount of 10% by weight or less based on the total amount of the epoxy resin and the curing agent.
0.5% by weight or more is preferable.

As other additives, colorants (such as carbon black), modifiers (such as silicone and silicone rubber), and ion trappers (such as hydrotalcite and antimony-bismuth hydrated oxides) can be used. When conductive particles such as carbon black are used in combination as a colorant, a particle size of 1 to achieve the object of the present invention.
It is preferable to use particles having a particle size of 0 μm or more of 1% by weight or less, and the addition amount thereof is preferably 3% by weight or less based on the total amount of the epoxy resin (A) and the curing agent (B).

As a general method for producing a molding material using the above-mentioned raw materials, a raw material mixture having a predetermined blending amount is sufficiently mixed by a mixer or the like, and then heated rolls are used.
By kneading with an extruder or the like, cooling and pulverizing, a molding material can be obtained. As a method of sealing an electronic component using the epoxy resin composition obtained in the present invention, a low-pressure transfer molding method is most common,
It is also possible by a method such as injection molding, compression molding and casting. The epoxy resin composition produced using the above-described means has excellent laser mark properties and electrical properties,
It has excellent moldability and reliability, and can be suitably used for sealing ICs, LSIs, and the like.

[0018]

EXAMPLES Examples of the present invention will be described below.
The present invention is not limited to this. Examples 1 to 5 Comparative Examples 1 to 4 First, after premixing (dry blending) various materials shown in Tables 1 and 2, a biaxial roll (roll surface temperature of about 8) was obtained.
(0 ° C.) for 10 minutes, followed by cooling and pulverization to produce the product.

[0019]

[Table 1]

[0020]

[Table 2]

The materials shown in Tables 1 and 2 are as follows. Biphenyl type epoxy resin: YX-4000H, Yuka Shell Epoxy Co., Ltd. Brominated epoxy resin: YDB-400, Toto Kasei Kogyo Co., Ltd. Aralkyl type phenolic resin: XL-225-3L, Mitsui Chemicals
Epoxy silane: A-187, trade name of Nippon Yunika Co., Ltd. Carbawax: Carnauba No. 1. Noda Chemical Co., Ltd.
Product name Polyethylene wax: PED-191, Clariant Japan Co., Ltd. Product name Phthalocyanine compound (absorbs a wavelength of 800 to 1200 nm,
In the general formula (4), R1, R2, R3 and R4 are all hydrogen and M is VO) Carbon beads: CB-3-500), trade name of Mitsui Mining Co., Ltd. Metal complex dye: Neo Super Black C-832R, Chuo Gosei Co., Ltd.
Product name Disazo dye: Chuo Sudan Black 141, Chuo Gosei Co., Ltd.
Trade name Azine dye: Spirit Black 920, trade name of Sumitomo Chemical Co., Ltd. Carbon black (particle size: 18 nm): manufactured by Mitsubishi Chemical Corporation Using this sealing material, using a transfer molding machine, mold temperature 180 Each test was performed under the conditions of a temperature of 70 ° C., a molding pressure of 70 kgf / cm ² and a curing time of 90 seconds. Spiral flow is EM
It was measured by M11-66. Hot hardness was measured with a shear hardness tester. Also, using this sealing material, a semiconductor element is molded by a transfer molding machine under the same conditions, and after post-curing (175 ° C./6 h), moisture resistance, solder heat resistance, laser markability, and electric characteristics (leakage current) Was evaluated. The volume resistivity was set to 100 mm in diameter and 3 mm in thickness by setting the disk mold in the transfer press and using the above sealing material.
After molding and hardening the disc, the measurement was performed with a volume resistance meter. The semiconductor device used for moisture resistance is SOP-28 pin, which absorbs moisture at 85 ° C./85 RH% for 72 hours + 215 ° C./90.
After pretreatment for 2 seconds (VPS), PCT (121 ° C / 2 atm)
To evaluate the presence or absence of disconnection of wiring on the chip. The semiconductor device used for solder heat resistance is a resin-encapsulated semiconductor device with QFP-80 pins (outer dimensions 20 × 14 × 2.0 mm)
The lead frame is made of 42 alloy material (no processing) and has a chip size of 8 × 10 mm. With respect to the resin-encapsulated semiconductor device thus obtained, the soldering heat resistance was set to 85 ° C / 85 after baking at 125 ° C / 24h.
After absorbing moisture for a predetermined time at RH%, 240 ° C / 10sec
The determination was made based on the crack occurrence rate of the resin-encapsulated semiconductor device when the above process was performed. The semiconductor device used for the laser mark property was QFP-54 pin, the package surface was printed with a YAG laser marking device, and the mark property was evaluated visually.

The conditions of the above YAG laser are shown below. YAG laser wavelength: 1064nm Laser power: 5J

The semiconductor device used for the electrical characteristics is LQFP
167 pins, and the presence or absence of leakage current was evaluated. Table 3 summarizes the above test results.

[0024]

[Table 3]

[0025]

According to the present invention, a phthalocyanine-based compound having V or VO as a central metal is incorporated as an essential component in an epoxy resin composition for encapsulating a semiconductor element containing an epoxy resin, a curing agent, a curing accelerator and an inorganic filler as main components. As a result, a sealing material excellent in laser markability, electrical characteristics, moldability, and reliability, and a semiconductor device using the same could be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5:56 3:00) (72) Inventor Masanobu Fujii 1772-1 Kajikubo, Yuki City, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Inside Shimodate Plant Co., Ltd. (72) Inventor Mitsuo Togawa 1772-1 Okakabo, Yuki-shi, Ibaraki Pref.Hitachi Kasei Kogyo Co., Ltd. Shimodate Plant F-term (reference) DE238 DJ008 DJ018 DK008 DL008 EN026 EU116 EW016 EW176 EY016 EZ007 FA048 FA088 FD018 FD142 FD156 GQ05 4M109 AA01 BA01 CA21 EA02 EA06 EB02 EB03 EB04 EB06 EB08 EB09 EB12 EB13 EB18 EB19 EC03 EC20

Claims (6)

[Claims] (1) an epoxy resin, (B) a curing agent,
An epoxy resin composition for semiconductor encapsulation comprising (C) a curing accelerator, (D) a phthalocyanine compound and (E) an inorganic filler as essential components. 2. A phthalocyanine compound having a central metal as V
The epoxy resin composition for semiconductor encapsulation according to claim 1, which has VO. 3. The epoxy resin composition for semiconductor encapsulation according to claim 1, wherein the epoxy resin has a melt viscosity at 150 ° C. of 0.5 Poise or less. 4. The epoxy resin for semiconductor encapsulation according to claim 1, wherein the content of the phthalocyanine compound is 0.05 to 15% by weight based on the total amount of the epoxy resin and the curing agent. Composition. 5. The epoxy resin composition for semiconductor encapsulation according to claim 1, wherein the composition contains 75 to 97% by weight of an inorganic filler. 6. A resin-sealed semiconductor device obtained by sealing a semiconductor element with the epoxy resin composition for semiconductor sealing according to claim 1.