KR101190765B1 - Epoxy resin composition for semiconductor - Google Patents

Abstract

The present invention relates to an epoxy resin composition for encapsulating a semiconductor device comprising an epoxy resin, a curing agent, an inorganic filler, a flame retardant, and other additives, wherein the transition metal oxide represented by the following Chemical Formulas 1 and 2 is used as a flame retardant in the total epoxy resin composition. By using the wt%, there is provided an environmentally friendly epoxy resin composition for encapsulating semiconductor devices that can improve workability while having good flame retardancy without using conventional harmful halides and antimony flame retardants.

Formula 1

_{2M 1x O · 3M 2y O 3} · 3.5H 2 O

In the above formula, M ₁ is an element selected from Group IIB on the periodic table, M ₂ is an element selected from Group IIIA on the periodic table, and x and y are integers between 1 and 10, respectively.

(2)

M _a (OH) _b

In the above formula, M is an element selected from group IIA on the periodic table, and a and b are each an integer between 1 and 10.

Description

Epoxy resin composition for semiconductor device encapsulation

1 is a graph showing the results of measuring the releasability of Examples and Comparative Examples.

The present invention relates to an epoxy resin composition for encapsulating a semiconductor device, and more particularly, to maintain all mechanical and electrical properties of an epoxy resin composition for encapsulating a package by a transfer molding method to protect chips during the manufacturing process of various semiconductor devices. The present invention relates to an epoxy resin composition for encapsulating an environmentally friendly semiconductor device, which has excellent flame retardant effect and excellent workability without using conventional halides and antimony that are harmful to the environment by using transition metal oxide as an inorganic flame retardant.

One of the most important characteristics in the epoxy resin composition for semiconductor encapsulation is flame retardancy, and conventionally, halogenated resins such as brominated epoxy resins and antimony oxide have been used in epoxy resin compositions for semiconductor chip encapsulation to have such flame retardant properties. Halogenated resins exhibit high flame retardant effects, but they emit toxic substances such as hydrogen halides upon combustion and adversely affect the global environment such as the generation of dioxins. In particular, the recent movement of regulations on the use of environmentally hazardous substances is becoming active all over the world, and the demand for this is gradually increasing in the field of semiconductor materials.

Accordingly, the development of raw materials to replace the flame retardant harmful to the environment is required, and various alternatives such as red phosphorus, organophosphorus compound, and metal hydroxide have been proposed. However, when red phosphorus or organophosphorus compound is used, the reliability required for epoxy resin composition for semiconductor encapsulation is accompanied, and metal hydroxide is inferior to resin composition such as mold release defect and appearance contamination during continuous operation.

Therefore, there has been a strong demand for the development of a technology that satisfies the requirements of the conventional resin composition for semiconductor encapsulation, particularly workability, even when a flame retardant which is harmless to the environment is used.

Accordingly, the present inventors studied two kinds of transition metal oxides of bromine and antimony, which are environmentally harmful among flame retardant components included in the epoxy resin composition for sealing a semiconductor device, in order to replace them. As an alternative to Oxide and controlling the weight ratio thereof, it was found that an epoxy resin for encapsulating semiconductor devices having excellent flame retardancy and workability could be manufactured, thereby completing the present invention.

Accordingly, an object of the present invention is to provide an environmentally friendly epoxy resin composition for encapsulating semiconductor elements while maintaining flame retardancy.

The epoxy resin composition for semiconductor element encapsulation of the present invention for achieving the above object is an epoxy resin composition for semiconductor element encapsulation comprising an epoxy resin, a curing agent, a curing accelerator, an inorganic filler, a flame retardant and other additives, It is characterized in that it comprises 1 to 10% by weight of the transition metal oxide represented by the formula (1) and 2 of the total epoxy resin composition.

_{2M 1x O · 3M 2y O 3} · 3.5H 2 O

In the above formula, M ₁ is an element selected from Group IIB on the periodic table, M ₂ is an element selected from Group IIIA on the periodic table, and x and y are integers between 1 and 10, respectively.

M _a (OH) _b

In the above formula, M is an element selected from group IIA on the periodic table, and a and b are each an integer between 1 and 10.

Hereinafter, the present invention will be described in more detail.

The epoxy resin composition for semiconductor element encapsulation according to the present invention uses two transition metal oxides as a flame retardant in a conventional composition including an epoxy resin, a curing agent, a curing catalyst, an inorganic filler, a flame retardant, and other additives.

Although the epoxy resin which can be used by this invention is not specifically limited, For example, a bisphenol-A epoxy resin, an alicyclic epoxy resin, a linear aliphatic epoxy resin, a cresol novolak-type epoxy resin, a biphenyl type epoxy resin, and a heterocyclic ring As at least one epoxy resin selected from the group consisting of an epoxy resin, an epoxy resin containing two or more epoxy groups in one molecule is preferable. At this time, the epoxy resin compounding amount is 2 to 20% by weight of the total epoxy resin composition. When the content of the epoxy resin is less than 2% by weight of the total resin composition, the physical properties of the epoxy resin such as adhesiveness and electrical insulation are lowered, and 20% by weight. If the percentage is exceeded, the moisture absorption increases, resulting in poor reliability of the semiconductor.

The curing agent is a group consisting of a variety of novolak resins and dihydrobiphenyl synthesized from xylol-type phenol resin represented by the following formula (3) alone or phenol novolak resin, cresol novolak resin, phenol alkyl resin, bisphenol A As the polyhydric phenol compound selected from the group consisting of at least one selected from the group, those containing two or more phenolic hydroxyl groups reacted with the epoxy resin component and cured in a molecular structure are used in combination.

Wherein n is an integer from 0 to 10.

In addition, a compound having an acid anhydride group or an amino group may be used as a curing agent of an epoxy resin. However, as a semiconductor encapsulating curing agent, a phenol-based curing agent having excellent physical properties such as moisture resistance, heat resistance, and storage property is preferably used.

The compounding quantity of the said hardening | curing agent in the epoxy resin composition of this invention is 2-20 weight%. If the blending amount of the curing agent is less than 2% by weight of the total epoxy resin composition may have a problem in the curability, if more than 20% by weight may cause a problem in the reliability due to the increase in the moisture absorption.

In addition, in view of moisture resistance, heat resistance, adhesion and mechanical properties, the compounding ratio of the epoxy resin and the curing agent preferably has a chemical equivalent ratio of epoxy resin to the curing agent in the range of 0.6 to 1.3, especially 0.8 to 1.2.

In addition, the filler used in the present invention may be used, such as silica, alumina, aluminum nitride or boron nitride, and can be used by mixing in a certain ratio having a shape of each phase and spherical. The content of the filler is preferably 70 to 95% by weight in the total epoxy resin composition. If the content of the filler is less than 70% by weight of the total epoxy resin composition may cause a problem in reliability due to the increase in moisture absorption, and in the case of more than 95% by weight may cause a problem in formability due to the increase in viscosity.

In addition to the composition as described above, the epoxy resin composition of the present invention may include a curing catalyst to promote the curing reaction of the epoxy resin and the phenol-based curing agent, wherein the curing catalyst is not limited as long as it can promote the curing reaction For example, imidazole compounds such as 2-methylimidazole, 2-ethyl4methylimidazole and 2-phenylimidazole, triethylamine, benzyldimethylamine, 2- (dimethylaminomethyl) phenol, Tertiary amine compounds such as 2,4,6-tris (dimethylaminomethyl) phenol, 1,8-diazabicyclo (5,4,0) undec-7-ene, triphenylphosphine, tributylphosphine, Organic phosphine compounds, such as tri (p-methylphenyl) phosphine, can be used, The compounding quantity of the range of 0.1-10 weight% is preferable in all the epoxy resin compositions. If the curing catalyst is used in less than 0.1% by weight of the total epoxy resin composition may cause a problem in the curability, when applied in excess of 10% by weight may cause a problem in reliability.

In the present invention, a flame retardant that is not particularly problematic in the environment is used. Specifically, the compound is represented by the following Chemical Formulas 1 and 2.

Formula 1

_{2M 1x O · 3M 2y O 3} · 3.5H 2 O

In the above formula, M ₁ is an element selected from Group IIB on the periodic table, M ₂ is an element selected from Group IIIA on the periodic table, and x and y are integers between 1 and 10, respectively.

The M ₁ includes, for example, zinc, and specific elements of M ₂ include boron, aluminum, and gallium, but are not limited thereto.

(2)

M _a (OH) _b

In the above formula, M is an element selected from Group IIA on the periodic table, and a and b are integers between 1 and 10. Specific elements of the M include magnesium, calcium, strontium and the like, but is not limited thereto.

In addition, the average particle size of the transition metal oxide represented by Formula 1 or 2 is preferably 0.1 to 10㎛, when using an average particle size of less than 0.1㎛ may cause a problem of contamination of the mold, and also 10㎛ The use of excess transition metal oxide can cause moldability problems.

In addition, in the present invention, in order to exhibit excellent flame retardancy, it is preferable to use the transition metal oxide represented by Formula 1 and the transition metal oxide represented by Formula 2 in a range satisfying the weight ratio of 1/15 to 1/5. Do. If used in a weight ratio outside this range, problems with mold release property may occur.

In addition to the above composition, the present epoxy resin composition includes a silane coupling agent for imparting a bonding force between the resin and the filler, a colorant such as carbon black and iron oxide, an ion trapping agent based on hydrotalcite, a long chain fatty acid, a metal salt of a long chain fatty acid, a paraffin wax, Of course, additives such as mold release agents such as canava wax and low stress agents such as modified silicone resins and modified polybutadiene may be optionally added as necessary, but are not limited thereto.

As the method for producing the epoxy resin composition of the present invention as described above, a melt kneading method is preferable and can be produced using, for example, a known kneading method such as a short-variety mixer, kneader, roll, single screw or twin screw extruder.

Hereinafter, the present invention will be described in more detail with reference to the following Examples, but the present invention is not limited thereto.

Examples 1-2 and Comparative Examples Comparative Examples 1-2

Next, the epoxy resin composition for encapsulating a semiconductor device was manufactured using the ingredients and contents shown in Table 1 below. The prepared resin composition was kneaded with a twin screw kneader in order to maintain even dispersion between the resin and the silica powder and melt mixed at a temperature of 100 to 130 ° C.

(Table 1)

Content (g) Example Comparative example One 2 One 2 Epoxy resin Biphenyl Epoxy Resin ⁽¹⁾ 55 55 55 55 Ortho Cresol Novolac Epoxy Resin ⁽²⁾ 35 35 35 35 Hardener Phenolic resin represented by the formula ⁽³⁾ 51 51 51 51 Filler Silica Powder 1 ⁽⁴⁾ 435 435 435 435 Silica Powder 2 ⁽⁵⁾ 425 415 425 415  Flame retardant Transition metal oxide represented by the formula (1 ^{) (6)} 4 5 20 25 Transition metal oxide represented by the formula (2 ⁾ 36 45 20 25 Colorant (carbon black) 2 2 2 2 Ion trapping agent (hydrotalcite type) 5 5 5 5 Curing accelerator (triphenylphosphine) One One One One Modifiers (Silicone Powder) 5 5 5 5 Release Agent (Canava Wax) 1.5 1.5 1.5 1.5 (week)
(1) 193 g / eq equivalent, 103 ° C melting point, (2) 197 g / eq equivalent, 55 ° C softening point
(3) Hydroxyl equivalent 175g / eq, Softening point: It is 66 degreeC.
(4) Specific surface area 3.5 m <2> / g, Average particle diameter 17.5 micrometers, (5) Specific surface area 4.6 m <2> / g, Average particle diameter 14.9 micrometer.
(6) Specific gravity 2.77, average particle diameter of 7㎛, M ₁ in the formula ( ₁₎ is Zn, M ₂ is B, x is 1, y is 2.
(7) Specific gravity 2.4, the average particle diameter of 0.8 ㎛, M in the formula (2) is Mg, a is 1, b is 2.

 Using the epoxy resin composition prepared as described above using a flame retardant measuring specimen mold in a heat transfer molding machine (pressure = 70kg / ㎠, temperature = 175 ℃, curing time = 120 seconds), and then using the experimental hood (Laboratory) FUME HOOD), the physical properties of each were measured as follows, and the results are shown in Tables 2 to 5 below.

(1) Evaluation of flame retardancy (UL94V): A specimen of 125 mm in length and 13 mm in width was prepared and measured by UL94 vertical flame retardancy test. The distance between the end of the specimen and the bottom is 30 cm, and the distance between the burner and the specimen is at least 150 mm.

(2) Evaluation of mold release property: After the mold release force test mold was cleaned in three moldings at 175 degrees for 300 seconds using melamine resin, the epoxy resin composition was molded at 175 degrees for 120 seconds, and then the mold and epoxy resin were measured using a stress gauge. The release force with the composition was measured.

(3) Mold cycle evaluation: The state of the mold surface was measured in the 32TSOP PKG continuous workability evaluation of the semiconductor mold molding machine (Fico Molding System).

Table 2
Example 1 Example 2 Sample One 2 3 4 5 One 2 3 4 5 T1 One One 0 One 0 One One One One One T2 3 8 5 6 5 6 5 4 5 5 T3 0 0 0 0 0 0 0 0 0 0 UP CLAMP NO NO NO NO NO NO NO NO NO NO GLOW COTTON NO NO NO NO NO NO NO NO NO NO Σ (T1 + T2) 30 30 T2 + T3 3 8 5 6 5 6 5 4 5 5 UL94 V- V-0 V-0

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(Table 3)

Comparative Example 1 Comparative Example 2 Sample One 2 3 4 5 One 2 3 4 5 T1 One One One One One Burn 34 7 One 15 T2 4 Burn One 12 11 - 0 One One One T3 0 - 0 0 0 - 0 0 0 0 UP CLAMP NO YES NO NO NO YES YES NO NO NO GLOW COTTON NO NO NO NO NO NO NO NO NO NO Σ (T1 + T2) FAIL FAIL T2 + T3 4 - One 12 11 - - - - - UL94 V- FAIL FAIL

As can be seen in the flame retardancy results of Tables 2 and 3, Examples 1 and 2 of the present invention showed significantly superior flame retardancy compared to Comparative Examples 1 and 2.

(Table 4)

Number of times Example 1 Example 2 Comparative Example 1 Comparative Example 2 One 87.05 87.05 110.55 110.55 2 68.9 70 62.75 80 3 52.45 52.44 102.5 78 4 49.3 48 88 92 5 23.75 23.55 75 78 6 26.7 26.7 70 65 7 32 33 65 60 8 16.7 15 64 65 9 21.6 20 73.3 62

 Table 4 shows the results of measurement of releasability of Examples and Comparative Examples. Examples 1 and 2 according to the present invention showed remarkably superior releasability than Comparative Example 1 and Comparative Example 2. After the graph of the results of Table 4, it can be seen through Example 1 and 2 of the present invention shows excellent release properties compared to the comparative example.

As described in detail above, the epoxy resin composition using the flame retardant according to the present invention instead of the flame retardant containing bromine or antimony, which is harmful to the human body as in the present invention, is controlled by V- in UL94V flame retardancy experiments by controlling the weight ratio of transition metal oxides. The present invention provides an environmentally friendly epoxy resin composition having excellent flame retardancy and zero workability in actual semiconductor assembly lines.

Claims (3)

In the epoxy resin composition for semiconductor element encapsulation comprising an epoxy resin, a curing agent, a curing accelerator, an inorganic filler, a flame retardant and other additives, The flame retardant comprises a transition metal oxide represented by the formula (1) and 2 to 1 to 10% by weight of the total epoxy resin composition The weight ratio of the transition metal oxide represented by Formula 1 to the transition metal oxide represented by Formula 2 is 1:15 to 1: 5 to satisfy the epoxy resin composition for sealing semiconductor elements. Formula 1 _{2M 1x O · 3M 2y O 3} · 3.5H 2 O In the above formula, M ₁ is an element selected from Group IIB on the periodic table, M ₂ is an element selected from Group IIIA on the periodic table, and x and y are integers between 1 and 10, respectively. (2) M _a (OH) _b In the above formula, M is an element selected from group IIA on the periodic table, and a and b are each an integer between 1 and 10. The epoxy resin composition for semiconductor element encapsulation according to claim 1, wherein the average particle size of the transition metal oxide is 0.1 to 10 µm. delete

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