KR20050069728A - Epoxy resin composition for sealing semiconductor element - Google Patents

Abstract

The present invention relates to an epoxy resin composition for encapsulating an environmentally friendly semiconductor device, and more particularly, to an epoxy resin composition comprising an epoxy resin, a curing agent, an inorganic filler, and other additives, which is represented by the following formula (1) Epoxy resin for encapsulating a semiconductor device comprising 5 to 15% by weight of an epoxy resin comprising a resin, 3 to 15% by weight of a curing agent, 75 to 90% by weight of an inorganic filler including 0 to 15% by weight of a metal-based inorganic flame retardant, and other additives It relates to a composition.

When the epoxy resin composition according to the present invention is used for encapsulating a semiconductor device, not only flame retardancy is improved, but also hygroscopicity and elastic modulus are lowered, thereby providing excellent crack resistance of the semiconductor package.

Formula 1

Here, n is an integer of 0-10.

Description

Epoxy resin composition for sealing semiconductor element

The present invention relates to an epoxy resin composition for encapsulating a semiconductor device, and more specifically, by using a xylock type epoxy resin represented by the following Chemical Formula 1, imparting flame retardancy, lowering hygroscopicity and elastic modulus, and having excellent crack resistance. It relates to a resin composition.

Here, n is an integer of 0-10.

The semiconductor is mounted on a board through a soldering process using lead. The semiconductor absorbs moisture in the air and has a constant moisture. The moisture absorbed is rapidly vaporized when the semiconductor is exposed to the soldering process to be mounted on the board, causing volume expansion, causing stress and causing package cracks. To the end.

The stress generated in the soldering process of the semiconductor increases in proportion to the moisture absorption of the semiconductor and increases in proportion to the soldering temperature.

Recently, according to the regulatory trend of environmentally harmful substances mainly in Europe, semiconductor companies are developing Pb-free soldering process which does not use environmentally harmful lead, and lead-free soldering process temperature is about 20 260 ° C is expected to be as high as 260 ° C. According to the lead-free soldering trend, high reliability is required for semiconductor encapsulants. To this end, it is important to secure a low modulus of elasticity to solve the low hygroscopicity and thermal stress of the encapsulant.

In addition, semiconductor encapsulants are subject to flame retardancy, like electronic components. To this end, Br and Sb compounds have been used as flame retardants in the past, but the use of these compounds is currently limited according to the environmental regulations.

Therefore, the necessity of the flame retardant resin is increasing in order to secure the flame retardancy of the semiconductor encapsulant while being environmentally friendly without using the existing flame retardant.

When using only conventional curing agent for epoxy encapsulant and epoxy resin, for example, biphenyl type epoxy resin, OCN (ortho cresol novolac) type epoxy resin, xylox type curing agent, phenol novolak type curing agent, There is a limit.

Therefore, in the present invention, as a result of the research to solve the above problems, by using an epoxy resin having a specific structure alone or mixed, excellent flame retardancy, low hygroscopicity and low modulus and for cracking semiconductor device encapsulation An epoxy resin composition was obtained, and the present invention was completed based on this.

Accordingly, an object of the present invention is to provide an epoxy resin composition for sealing a semiconductor device having excellent flame retardancy, low hygroscopicity and low elastic modulus, and excellent crack resistance.

The epoxy resin composition for encapsulating a semiconductor device for achieving the object of the present invention is an epoxy resin composition comprising an epoxy resin, a curing agent, an inorganic filler, and other additives, epoxy comprising a xylock type epoxy resin represented by the following formula (1) 75 to 90% by weight of the inorganic filler including 5 to 15% by weight of the resin, 3 to 15% by weight of the curing agent, 0 to 15% by weight of the metal-based inorganic flame retardant, and the others include other additives.

Formula 1

Here, n is an integer of 0-10.

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

As described above, the epoxy resin composition for encapsulating a semiconductor device of the present invention includes an epoxy resin, a curing agent, an inorganic filler, and other additives.

As the epoxy resin component, a xylol compound represented by the following Chemical Formula 1 may be used alone or mixed with a biphenyl epoxy resin represented by the following Chemical Formula 2 or an OCN (ortho cresol novolac) epoxy resin represented by the following Chemical Formula 3 Use it.

The use amount of the epoxy resin in the present invention is 5 to 15% by weight, of which the xylol-type epoxy resin is preferably used at 50% or more based on the equivalent ratio. If the amount of the epoxy resin used is less than 5% by weight, moldability cannot be achieved. If the amount of the epoxy resin is used, the synergistic effect is hardly expected. In addition, when the content of the xylol-type epoxy resin represented by the following formula (1) is used in less than 50% by weight ratio, it is difficult to expect a synergistic effect according to the addition amount.

Formula 1

Here, n is an integer of 0-10.

Here, n is an integer of 0-10.

The curing agent used in the present invention is preferably a xylock type curing agent represented by the following general formula (4) or a phenol novolac type curing agent represented by the following general formula (5), and the total amount of the curing agent used is preferably 3 to 15% by weight. If the total content of the curing agent is added less than 3% by weight, moldability cannot be achieved, and when the total content of the curing agent is more than 15% by weight, curing occurs so quickly that it is difficult to expect a synergistic effect depending on the amount added.

Here, n is an integer of 0-10.

Here, n is an integer of 0-10.

Inorganic fillers used in the present invention may use high-purity natural silica, synthetic silica, fused silica, alumina, and the like, but the molten silica is preferably made of 75% by weight or more of the total inorganic filler. When added below 75% by weight, the moldability desired in the present invention cannot be achieved. The total amount of the inorganic filler is preferably 70 to 90% by weight.

On the other hand, when using the epoxy resin represented by the formula (1) alone, when using the inorganic filler more than 85% by weight can be ensured flame retardant without using an auxiliary flame retardant, when using less than 85% by weight metal-based inorganic Flame retardant can be used within 10% by weight of flame retardant.

The flame retardant used in the present invention may use 0 to 15% by weight and may use a metal-based inorganic flame retardant including metal hydroxide, for example, MgOH, MgO and the like.

In addition, the composition of the present invention may further include a release agent, a colorant, a coupling agent, a modifier, a curing accelerator, and the like, which are generally applied, as optional components. At this time, the colorant may be included in the content of less than 1.0% by weight, the curing accelerator 0.1 to 1.0% by weight and other additives 1 to 5% by weight.

The epoxy resin composition for encapsulation of the semiconductor device of the present invention is mixed with each raw material as described above and then melt mixed at a temperature of 100 ℃ to 130 ℃ using a melt mixer (kneader) to cool to room temperature and pulverized into a powder state and blended It may be prepared by a general manufacturing method through the process.

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

Examples 1-4

As the epoxy resin, the resin of formula 1 (epoxy equivalent = 240 g / eq.) And the resin of formula 2 (epoxy equivalent = 193 g / eq.) Were used, and the curing agent was the resin of formula 4 (active group equivalent = 175 g / eq. .) Is weighed as shown in Table 1 below and mixed with the other ingredients, followed by melt mixing, cooling, grinding, and blending process and tableting to a certain size.

Using the epoxy resin composition prepared as described above to measure the flow (Spiral Flow) in a heat transfer molding machine (pressure = 70kg / ㎠, temperature = 175 ℃, curing time = 120 seconds), moisture absorption measurement specimens, adhesion Specimens and flame retardant test specimens were prepared and then post-cured at 175 ° C. for 6 hours to measure hygroscopicity, adhesion and flame retardancy, and were placed in an MQFP package (body size: 28 mm × 28 mm, 208 leads) with SiN chips. After molding, post-curing at 175 ° C for 6 hours, absorbing at constant temperature and humidity (85 ° C / 85% RH), and applying three times of IR-reflow (maximum temperature = 260 ° C), followed by ultrasonic flaw detector (SAT The number of cracks was observed using) and is shown in Table 1 below.

In addition, using the epoxy resin composition prepared as described above using a heat transfer molding machine (pressure = 70kg / ㎠, temperature = 175 ℃, curing time = 90 seconds) to prepare a specimen of length 48mm, width 12mm, thickness 3mm It was. After each four specimens were post-cured at 175 ℃ for 6 hours, the flexural strength and flexural modulus of each specimen were measured at 225 ℃ and the results are shown in Table 1 below.

Comparative Examples 1 to 4

As the epoxy resin, the resin of the formula (1) and the resin of the formula (2) were used, and as the curing agent, the resin of the formula (4) was measured in the same manner as in Examples 1 to 4 as shown in Table 1 below.

Examples 5-8

As the epoxy resin, the resin of formula 1 (epoxy equivalent = 240 g / eq.) And the resin of formula 3 (epoxy equivalent = 199 g / eq.) Were used, and the curing agent was the resin of formula 5 (active group equivalent = 107 g / eq. .) Was weighed as in Table 2 and carried out in the same manner as in Examples 1 to 4.

Comparative Examples 5-8

As the epoxy resin, the resin of Formula 1 and the resin of Formula 3 were used, and the curing agent was measured in the same manner as in Examples 1 to 4 by measuring the resin of Formula 5 as shown in Table 2 below.

division unit Example Comparative example One 2 3 4 One 2 3 4 Formula 1 weight% 7 4 9 11 3 0 3 4 Formula 2 0 3 0 0 4 7 6 7 Formula 4 5 5 7 8 5 5 7 8 Inorganic flame retardant ¹⁾ 5 8 5 8 Silica 85 85 75 67 85 85 70 67 Additive ²⁾ 2.7 2.7 3.6 5.4 2.7 2.7 3.6 5.4 Curing accelerator ³⁾ 0.3 0.3 0.4 0.6 0.3 0.3 0.4 0.6 Property evaluation result liquidity inch 26 27 33 39 28 29 32 38 Curing time second 25 24 25 25 24 23 25 25 Tg ℃ 110 112 109 111 115 119 109 110 Adhesive force (before absorption) Mpa 5.8 5.3 6.5 7.0 4.9 4.2 6.6 6.9 Adhesive force (after moisture absorption) 5.6 5.0 6.1 6.7 4.7 3.9 6.4 6.7 Flexural strength Kgf / mm2 0.897 0.884 0.785 0.698 0.895 0.890 0.788 0.689 Flexural modulus 84.1 91.2 75.4 68.2 100.3 109.8 75.9 68.8 Moisture absorption % 0.251 0.285 0.351 0.409 0.302 0.334 0.344 0.399 UL-94V - V-0 V-0 V-0 V-0 V-1 V-1 V-1 V-1 Crack resistance 12hr / s Number of cracks / unit 0/22 0/22 1/22 2/22 0/22 2/22 1/22 3/22 24hr / s 0/22 0/22 3/22 5/22 1/22 3/22 2/22 4/22 48hr / s 0/22 1/22 5/22 8/22 2/22 5/22 6/22 7/22

1) MgOH

2) Silicone Coupling Agent, Wax

3) Triphenylphosphate (TPP)

division unit Example Comparative example 5 6 7 8 5 6 7 8 Formula 1 weight% 7 4 9 11 3 0 3 4 Formula 3 0 3 0 0 4 7 6 7 Formula 5 5 5 7 8 5 5 7 8 Inorganic flame retardant ¹⁾ 5 8 5 8 Silica 85 85 75 67 85 85 75 67 Additive ²⁾ 2.7 2.7 3.6 5.4 2.7 2.7 3.6 5.4 Curing accelerator ³⁾ 0.3 0.3 0.4 0.6 0.3 0.3 0.4 0.6 Property evaluation result liquidity inch 19 20 25 31 21 22 25 31 Curing time second 20 19 20 20 19 18 20 20 Tg ℃ 126 133 124 125 141 150 123 125 Adhesive force (before absorption) Mpa 4.3 3.9 4.8 5.3 3.5 2.9 4.9 5.5 Adhesive force (after moisture absorption) 3.8 3.3 4.3 4.7 3.1 2.3 4.4 4.9 Flexural strength Kgf / mm2 1.124 1.122 1.048 0.945 1.131 1.129 1.052 0.921 Flexural modulus 104.5 121.5 96.8 87.5 119.5 132.5 97.0 88.9 Moisture absorption % 0.403 0.438 0.408 0.542 0.450 0.485 0.495 0.448 UL-94V - V-0 V-0 V-0 V-0 V-1 V-1 V-1 V-1 Crack resistance 12hr / s Number of cracks / unit 0/22 0/22 3/22 4/22 1/22 4/22 3/22 3/22 24hr / s 0/22 1/22 5/22 9/22 3/22 8/22 6/22 9/22 48hr / s 1/22 2/22 8/22 12/22 5/22 13/22 7/22 9/22

1) MgOH

2) silicone coupling agent, wax

3) Triphenylphosphate (TPP)

The measuring method for each property is as follows.

Spiral flow measurement

Using a flowable mold of the EMMI-I-66 standard, it is measured by a heat transfer molding machine (pressure = 70kg / cm 2, temperature = 175 ° C, curing time = 120 seconds).

Curing Time (G / T) Measurement

A stopwatch is started immediately after placing a sample of 1 to 3 g of powder powder having a particle size of 3 mm or less on a hot plate at 175 ° C using a spatula, and a thin film is formed on the surface. The stopwatch is quickly stopped and the time is measured by drawing the film with brass pins and ending the point where the sample starts to harden as the sample hardens.

Glass Transition Temperature (Tg) Measurement

After molding in a heat transfer molding machine (pressure = 70kg / cm2, temperature = 175 ° C, curing time = 120 seconds) using a specimen manufacturing mold (width = 35 mm, length = 5 mm, thickness = 3 mm) for measuring Tg. After 6 hours post-curing in an oven at 175 ° C., the specimens were cut (width = 5 mm, length = 5 mm, thickness = 3 mm) and measured by TMA (Thermo-Mechanical Analyzer).

Flexural Strength and Flexural Modulus Measurement

The specimen is placed as shown in FIG. 1, and the flexural strength value is calculated as in Equation 1, and the flexural modulus is calculated as in Equation 2.

Hygroscopicity measurement

Molded in a heat transfer molding machine (pressure = 70kg / cm 2, temperature = 175 ° C, curing time = 120 seconds) using a disc specimen manufacturing mold (diameter = 33 mm, thickness = 3.1 mm) for moisture absorption measurement, and then oven at 175 ° C. After 6 hours of post-curing at, the specimen was absorbed for 24 hours under 121 ° C, 2 atmospheres, and 100% RH PCT (Pressure Cooler Test) conditions, and the moisture absorption rate was measured by measuring the weight before and after absorption.

Adhesion Measurement

In order to produce a specimen of the form as shown in Figure 3 using a copper frame and a mold in a heat transfer molding machine (pressure = 70kg / ㎠, temperature = 175 ℃, curing time = 120 seconds) after molding for 6 hours in an oven at 175 ℃ After the post-curing for a period of time, and before the 48 hours at 85 ℃ / 85% RH conditions and the tensile force in the direction as shown in Figure 4 with a Universal Testing Machine (UTM) while applying a load at the point where the copper frame falls with the epoxy resin composition It measures and converts into adhesive force value (MPa).

Flame Retardant Measurement

In order to prepare the specimen, the test specimen was manufactured to a length of 125 mm, a width of 13 mm, and a thickness of 3 mm in a heat transfer molding machine (pressure = 70kg / ㎠, temperature = 175 ° C, curing time = 90 seconds) using a mold After curing after curing for 6 hours in an oven at 175 ° C, the prepared specimen was placed in a methane gas burner in the longitudinal direction of the specimen as shown in FIG. 2 and then burned continuously two times. After burning the flame in the burner for the first 10 seconds and then removing the flame in the burner, the flame remains on the specimen after T1 and after burning the flame in the burner for 10 seconds after T1, the flame remains on the specimen. Time is T2. The time to burn without flame after the second combustion is defined as T3. Five specimens were prepared per example to determine whether V-0 by repeating the above experiment five times.

When the semiconductor device is encapsulated using the epoxy resin composition prepared according to the present invention, excellent flame retardancy and low hygroscopicity and low elastic modulus can be ensured, thereby increasing crack resistance.

1 is a view schematically showing a device for testing the flexural strength and flexural elasticity of the composition according to the present invention.

2 is a schematic illustration of an apparatus for testing the adhesion of a composition according to the invention.

3 is a diagram schematically illustrating a method for experimenting flame retardancy of a composition according to the present invention.

※ Explanation of code about main part of drawing ※

1: epoxy resin composition 2: copper frame

←, →: direction in which tension is applied

Claims (3)

Epoxy resin composition comprising an epoxy resin, a curing agent, an inorganic filler and other additives, 5 to 15% by weight of the epoxy resin, including 3 to 15% by weight, 0 to 15 An epoxy resin composition for encapsulating a semiconductor device, comprising from 75 to 90% by weight of an inorganic filler including a metal-based inorganic flame retardant by weight and other additives; Formula 1 Here, n is an integer of 0-10. The resin composition for encapsulating semiconductor devices according to claim 1, wherein the xylock type epoxy resin represented by Chemical Formula 1 is contained in an equivalent ratio of 50% based on the total epoxy resin content. The resin of claim 1, wherein the epoxy resin further comprises at least one component selected from the group consisting of ortho cresol novolac type, biphenyl type, polyfunctional type, and dicyclopentadiene type. Composition.