KR20190053057A - Epoxy resin composition for encapsulating semiconductor device and semiconductor device encapsulated using the same - Google Patents

Abstract

The present invention relates to an epoxy resin composition for sealing a semiconductor device, capable of increasing reliability of a semiconductor device, and to a semiconductor device sealed by using the same. The epoxy resin composition for sealing a semiconductor device of the present invention comprises an epoxy resin, a curing agent, an inorganic filler, and a curing accelerator, wherein the epoxy resin includes a bisphenol epoxy resin modified with polyurethane.

Description

TECHNICAL FIELD [0001] The present invention relates to an epoxy resin composition for encapsulating semiconductor devices, and a semiconductor device encapsulated with the epoxy resin composition. [0002] EPOXY RESIN COMPOSITION FOR ENCAPSULATING SEMICONDUCTOR DEVICE AND SEMICONDUCTOR DEVICE ENCAPSULATED USING THE SAME [

The present invention relates to an epoxy resin composition for sealing a semiconductor device and a semiconductor device sealed with the epoxy resin composition. More specifically, the present invention lowers the modulus at high temperatures The reliability of the semiconductor device can be enhanced, To an epoxy resin composition for sealing a semiconductor device which can increase an adhesive strength and is excellent in fluidity, and a semiconductor device which is sealed using the composition.

BACKGROUND ART [0002] Transparent molding using an epoxy resin composition is widely used as a method of packaging semiconductor devices such as IC (integrated circuit) and LSI (large scale integration) and obtaining a semiconductor device because of its low cost and suitable for mass production. The epoxy resin composition for semiconductor encapsulation generally comprises an epoxy resin, a curing agent, an inorganic filler, and the like.

However, due to the miniaturization, light weight, and high performance of electronic products, semiconductor chips have become thinner, higher integration and / or surface mounting have increased, which can not be solved by conventional epoxy resin compositions. In particular, there is a demand for a semiconductor device having excellent reliability as the semiconductor device is thinned and left at a high temperature.

The object of the present invention is to lower the modulus at high temperatures And to provide an epoxy resin composition for semiconductor device encapsulation which can enhance the reliability of a semiconductor device.

Another object of the present invention is to provide an epoxy resin composition for sealing a semiconductor element which can increase the adhesive force with a chip or a substrate.

It is still another object of the present invention to provide an epoxy resin composition for sealing semiconductor devices having excellent flowability.

It is still another object of the present invention to provide a semiconductor device sealed with the epoxy resin composition as described above.

The epoxy resin composition for semiconductor device encapsulation of the present invention comprises an epoxy resin, a curing agent, an inorganic filler and a curing accelerator, and the epoxy resin may include a bisphenol epoxy resin modified with a polyurethane.

The present invention provides a semiconductor device sealed with an epoxy resin composition for semiconductor device encapsulation according to the present invention.

The present invention Lowering the modulus at high temperatures There is provided an epoxy resin composition for sealing a semiconductor element which can increase the reliability of a semiconductor element.

The present invention provides an epoxy resin composition for sealing a semiconductor device capable of enhancing adhesion to a chip or a substrate.

The present invention provides an epoxy resin composition for sealing semiconductor devices having excellent flowability.

The present invention provides a semiconductor device sealed with an epoxy resin composition of the present invention.

As used herein, "high temperature" may mean 260 ° C ± 5 ° C, preferably 260 ° C.

The present inventors have conducted extensive studies to develop an epoxy resin for sealing a semiconductor element which can increase the reliability of a semiconductor element by lowering the modulus at a high temperature and can increase the adhesive force with a chip or a substrate and has excellent fluidity. As a result, The present invention has been accomplished on the basis of the finding that the above object can be achieved by including the epoxy resin described above.

The epoxy resin composition according to the present invention comprises an epoxy resin, a curing agent, an inorganic filler and a curing accelerator, and the epoxy resin may include a bisphenol epoxy resin modified with a polyurethane. Preferably, the polyurethane-modified bisphenol epoxy resin may include an epoxy resin represented by the following formula (1). The epoxy resin of the following formula (1) lowers the modulus at high temperature, thereby enhancing the reliability of the semiconductor device. In addition, the epoxy resin of the following formula (1) contains a polar functional group, so that the adhesive strength to the chip or the metal substrate can be increased and the fluidity can be improved.

Epoxy resin

The epoxy resin may comprise a bisphenol epoxy resin modified with a polyurethane. Preferably, the polyurethane-modified bisphenol epoxy resin may comprise an epoxy resin of the formula (1): < EMI ID =

≪ Formula 1 >

(Wherein, A is a residue of a polyurethane polymer,

R is a single bond or C (R ¹ R ² ), R ¹ and R ² are each independently hydrogen, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ¹ and R ² are Substituted or unsubstituted alicyclic rings having 6 to 20 carbon atoms,

n and m are each independently an integer of 1 to 100).

The "substituted" in the "substituted or unsubstituted" means that at least one hydrogen atom of the functional group is substituted with an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, a halogen atom, or a hydroxyl group.

Preferably, A may be a residue of a polyurethane polymer having a polar functional group. The polar functional group is bonded to the chip or metal substrate The adhesive strength can be increased. The "polar functional group" may be a hydroxyl group, a monovalent functional group having a hydroxyl group, or a divalent functional group having a hydroxyl group.

Preferably, R is a single bond or C (R ¹ R ² ) (wherein R ¹ and R ² are each independently hydrogen, an alkyl group having 1 to 10 carbon atoms).

Preferably, n may be an integer from 1 to 10. Within the above range, the modulus at a high temperature is lowered and the viscosity is low, so that the fluidity of the epoxy resin composition can be increased.

Preferably, m may be an integer from 1 to 10. Within the above range, the modulus at a high temperature is lowered and the viscosity is low, so that the fluidity of the epoxy resin composition can be increased.

The epoxy resin of Formula 1 may include an epoxy resin obtained by modifying a polyurethane with a bisphenol epoxy resin. The epoxy resin of Formula 1 may be prepared by a conventional method known to those skilled in the art or may be a commercially available product (e.g., EPU-73B, ADEKA).

The epoxy resin of Formula 1 may have a weight average molecular weight of 490 g / mol to 3,000 g / mol, for example, 490 g / mol to 1,000 g / mol. Within this range, the viscosity of the epoxy resin composition is not high, which is advantageous for sealing semiconductor devices.

The epoxy resin of Formula 1 may have an epoxy equivalent of 200 g / eq to 1,000 g / eq, for example, 200 g / eq to 350 g / eq. Within this range, it may be advantageous for sealing semiconductor devices.

The epoxy resin of Formula 1 may be contained in the composition for sealing a semiconductor device in an amount of 0.1 to 5 wt%, for example, 0.2 to 2 wt%. Within the above range, it is possible to lower the modulus at high temperature, increase the adhesive strength, and increase the fluidity.

The epoxy resin of Formula 1 may be contained in an amount of 1 wt% to 30 wt%, for example, 3 wt% to 15 wt% of the entire epoxy resin. Within the above range, it is possible to lower the modulus at high temperature, increase the adhesive strength, and increase the fluidity.

The epoxy resin may further include an epoxy resin generally used for sealing a semiconductor device in addition to the epoxy resin of the above formula (1). The epoxy resin of Formula 1 is not particularly limited, but may be a liquid having a high viscosity. By further including an epoxy resin other than the epoxy resin of Formula 1, processing of the epoxy resin composition can be facilitated.

Specifically, the epoxy resin is an epoxy compound containing two or more epoxy groups in the molecule, and may include a non-urethane-based epoxy resin not containing a polyurethane. For example, the epoxy resin is an epoxy resin obtained by epoxidating a condensate of phenol or alkyl phenol and hydroxybenzaldehyde, a phenol aralkyl type epoxy resin, a phenol novolak type epoxy resin, a cresol novolak type epoxy resin, a multifunctional epoxy Resin, naphthol novolak type epoxy resin, novolak type epoxy resin of bisphenol A / bisphenol F / bisphenol AD, glycidyl ether of bisphenol A / bisphenol F / bisphenol AD, bishydroxybiphenyl type epoxy resin, dicyclopenta Diene-based epoxy resins and the like. More specifically, the epoxy resin may include at least one of a cresol novolak-type epoxy resin, a multifunctional epoxy resin, a phenol aralkyl-type epoxy resin, and a biphenyl-type epoxy resin.

For example, the epoxy resin may be at least one of a biphenyl type epoxy resin of the following formula (2) and a phenol aralkyl type epoxy resin of the following formula (3)

(2)

(Wherein R represents an alkyl group having 1 to 4 carbon atoms, and n has an average value of 0 to 7).

(3)

(In the above formula (3), the average value of n is 1 to 7).

The epoxy resin may be used singly or in combination, and may be added in the form of an additive compound prepared by subjecting an epoxy resin to a linear reaction such as a curing agent, a curing accelerator, a releasing agent, a coupling agent, a stress relieving agent and a melt master batch. It can also be used.

The epoxy resin may be contained in an amount of 0.5 to 20% by weight, specifically 3 to 15% by weight in the epoxy resin composition for sealing a semiconductor device. Within this range, the curability of the composition may not be deteriorated.

Hardener

The curing agent is selected from the group consisting of phenol aralkyl type phenol resin, phenol novolac type phenol resin, xylock type phenol resin, cresol novolak type phenol resin, naphthol type phenol resin, terpene type phenol resin, Novolak phenol resins synthesized from bisphenol A and resole, tricyclic (hydroxyphenyl) methane, polyhydric phenol compounds including dihydroxybiphenyl, acid anhydrides including maleic anhydride and phthalic anhydride, meta-phenylenediamine, Aromatic amines such as diaminodiphenylmethane and diaminodiphenylsulfone, and the like. The curing agent may be a phenol resin having at least one hydroxyl group.

In one embodiment, the curing agent can be at least one of a xylyl-type phenolic resin of formula (4), a phenol aralkyl phenolic resin of formula (5)

≪ Formula 4 >

(The average value of n in the above formula (4) is 0 to 7).

≪ Formula 5 >

(The average value of n in Formula 5 is 1 to 7).

The curing agent may be present in an amount of from 0.1% to 15%, such as from 0.5% to 13%, such as from 1% to 10%, such as from 2% to 8% . Within this range, the curability of the composition may not be deteriorated.

The blending ratio of the epoxy resin and the curing agent can be adjusted according to the requirements of mechanical properties and moisture resistance reliability in the package. For example, the chemical equivalent ratio of the epoxy resin to the curing agent may be from 0.95 to 3, and may be specifically from 1 to 2, more specifically from 1 to 1.75. When the compounding ratio of the epoxy resin and the curing agent is in the above range, excellent strength can be realized after curing the epoxy resin composition.

Inorganic filler

The inorganic filler is intended to improve the mechanical properties and low stress of the epoxy resin composition. As the inorganic filler, general inorganic fillers used in semiconductor encapsulants can be used without limitation, and are not particularly limited. Examples of the inorganic filler include fused silica, crystalline silica, calcium carbonate, magnesium carbonate, alumina, magnesia, clay, talc, calcium silicate, titanium oxide, antimony oxide, . These may be used alone or in combination.

Preferably, fused silica having a low linear expansion coefficient is used for low stress. The fused silica refers to amorphous silica having a true specific gravity of 2.3 or less and includes amorphous silica obtained by melting crystalline silica or synthesized from various raw materials. Although the shape and the particle diameter of the fused silica are not particularly limited, the spherical fused silica having an average particle diameter of 5 to 30 탆 is contained in an amount of 50 to 99% by weight, the spherical fused silica having an average particle diameter of 0.001 to 1 탆 is contained in an amount of 1 to 50% To 40% by weight to 100% by weight with respect to the total filler. Further, the maximum particle diameter can be adjusted to any one of 45 탆, 55 탆 and 75 탆 according to the application. Since the spherical fused silica may contain conductive carbon as a foreign substance on the surface of the silica, it is also important to select a substance having a small amount of polar foreign substances.

The amount of the inorganic filler to be used varies depending on required properties such as moldability, low stress, and high temperature strength. In embodiments, the inorganic filler may comprise from 70% to 95%, such as 70% to 94% or 70% to 93% by weight of the epoxy resin composition. Within this range, there can be obtained an effect of securing the fluidity and reliability of the composition.

Hardening accelerator

The curing accelerator is a substance that promotes the reaction between the epoxy resin and the curing agent. As the curing accelerator, for example, tertiary amines, organometallic compounds, organic phosphorus compounds, imidazole compounds, and boron compounds can be used. Tertiary amines include benzyldimethylamine, triethanolamine, triethylenediamine, diethylaminoethanol, tri (dimethylaminomethyl) phenol, 2-2- (dimethylaminomethyl) phenol, 2,4,6-tris ) Phenol and tri-2-ethylhexyl acid salt. Specific examples of the organometallic compound include chromium acetylacetonate, zinc acetylacetonate, nickel acetylacetonate, and the like. Organic phosphorus compounds include tris-4-methoxyphosphine, tetrabutylphosphonium bromide, tetraphenylphosphonium bromide, phenylphosphine, diphenylphosphine, triphenylphosphine, triphenylphosphine triphenylborane, triphenylphosphine Pin-1,4-benzoquinone adducts and the like. Imidazole compounds include, but are not limited to, 2-phenyl-4 methylimidazole, 2-methylimidazole, 2-phenylimidazole, 2-aminoimidazole, -Methylimidazole, 2-heptadecylimidazole, and the like, but the present invention is not limited thereto. Specific examples of the boron compound include tetraphenylphosphonium-tetraphenylborate, triphenylphosphine tetraphenylborate, tetraphenylboron salt, trifluoroborane-n-hexylamine, trifluoroborane monoethylamine, tetrafluoroborane Triethylamine, tetrafluoroborane amine, and the like. In addition, 1,5-diazabicyclo [4.3.0] non-5-ene (1,5-diazabicyclo [4.3.0] non-5-ene: DBN), 1,8-diazabicyclo [5.4. Diazabicyclo [5.4.0] undec-7-ene: DBU) and phenol novolac resin salt. However, the present invention is not limited thereto.

The curing accelerator may be contained in the epoxy resin composition in an amount of 0.01 wt% to 5 wt%, preferably 0.05 wt% to 3 wt%, more preferably 0.1 wt% to 2 wt%. The strength of the cured product of the epoxy resin composition in the above range can be improved.

In addition to the above components, the epoxy resin composition according to the present invention may further include at least one of a coupling agent, a release agent, and a colorant.

Coupling agent

The coupling agent is for improving the interface strength by reacting between the epoxy resin and the inorganic filler, and may be, for example, a silane coupling agent. The silane coupling agent is not particularly limited as long as it reacts between the epoxy resin and the inorganic filler to improve the interface strength between the epoxy resin and the inorganic filler. Specific examples of the silane coupling agent include epoxy silane, aminosilane, ureido silane, mercaptosilane, and the like. The coupling agent may be used alone or in combination.

The coupling agent may be contained in an amount of 0.01 wt% to 5 wt%, preferably 0.05 wt% to 3 wt%, and more preferably 0.1 wt% to 2 wt% based on the total weight of the epoxy resin composition. The strength of the cured product of the epoxy resin composition in the above range can be improved.

Release agent

As the releasing agent, at least one selected from the group consisting of paraffin wax, ester wax, higher fatty acid, higher fatty acid metal salt, natural fatty acid and natural fatty acid metal salt can be used. The release agent may be contained in an amount of 0.1 wt% to 1 wt% of the epoxy resin composition.

coloring agent

The coloring agent is for laser marking of the semiconductor element sealing material, and coloring agents well known in the art can be used and are not particularly limited. For example, the colorant may include one or more of carbon black, titanium black, titanium nitride, dicopper hydroxide phosphate, iron oxide, mica. The colorant may be contained in an amount of 0.01 wt% to 5 wt%, preferably 0.05 wt% to 3 wt%, more preferably 0.1 wt% to 2 wt% based on the total weight of the epoxy resin composition.

In addition, the epoxy resin composition of the present invention may contain a stress-relieving agent such as a modified silicone oil, a silicone powder, and a silicone resin to the extent that the object of the present invention is not impaired; Antioxidants such as Tetrakis [methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane; A flame retardant such as aluminum hydroxide, and the like may be further added as needed.

The epoxy resin composition is prepared by uniformly mixing the above components uniformly at a predetermined mixing ratio using a Hensel mixer or Lodige mixer, and then kneading the mixture with a roll-mill or a kneader Melting and kneading, and then cooling and pulverizing to obtain a final powder product.

The epoxy resin composition of the present invention as described above can be applied to semiconductor devices, particularly semiconductor devices requiring high shrinkage and high elasticity properties. As a method of sealing a semiconductor element using the epoxy resin composition obtained in the present invention, a low pressure transfer molding method can be generally used. However, it is also possible to perform molding by an injection molding method or a casting method.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense. The contents not described here are sufficiently technically inferior to those skilled in the art, and a description thereof will be omitted.

Specific specifications of the components used in the following examples and comparative examples are as follows.

(A) an epoxy resin

(A1) Epoxy resin (EPU-73B, ADEKA, epoxy resin of formula 1, n = 2, epoxy equivalence: 200 g / eq)

(A2) biphenyl type epoxy resin (YX-4000H, Nippon Kayaku)

(B) Hardener: Xyloclock type phenol resin (HE100C-10, Air Water)

(C) Inorganic filler: 9: 1 (by weight) mixture of spherical fused silica having an average particle diameter of 18 탆 and spherical fused silica having an average particle diameter of 0.5 탆

(D) Curing accelerator: imidazole compound (2P4MHZ, Nippon-Gosei)

(E) Coupling agent: (E1) A mixture of epoxy-containing trimethoxysilane KBM-303 (Shinetsu) and (E2) methyltrimethoxysilane SZ-6070 (Dow Corning Chemicals)

(F) Colorant: Carbon black MA-600B (manufactured by Mitsubishi Chemical Corporation)

(G) Release agent: Carnauba wax

(H) Polyurethane

Example  And Comparative Example

Each of the components was weighed according to the composition (unit: parts by weight) shown in the following Table 1, and then uniformly mixed using a Henschel mixer to prepare a powdery primary composition. Thereafter, the mixture was melt-kneaded at 90 to 110 ° C using a continuous kneader, followed by cooling and pulverization, thereby preparing an epoxy resin composition for sealing semiconductor devices.

Example Comparative Example One 2 3 4 One 2 (A) (A1) 0.535 1.073 0.321 1.614 0 0 (A2) 10.169 9.659 10.372 9.147 10.676 8.556 (B) 3.978 3.949 3.99 3.919 4.007 3.212 (C) 84 84 84 84 84 84 (D) 0.428 0.429 0.427 0.43 0.427 0.342 (E) (E1) 0.2 0.2 0.2 0.2 0.2 0.2 (E2) 0.2 0.2 0.2 0.2 0.2 0.2 (F) 0.2 0.2 0.2 0.2 0.2 0.2 (G) 0.29 0.29 0.29 0.29 0.29 0.29 (H) 0 0 0 0 0 3 total 100 100 100 100 100 100

The physical properties of the epoxy resin compositions of the examples and comparative examples thus prepared were measured according to the following properties evaluation methods. The measurement results are shown in Table 2.

Property evaluation method

(1) Flowability (inch): An epoxy resin composition was injected into a mold for spiral flow measurement according to EMMI-1-66 at a molding temperature of 175 캜 and a molding pressure of 70 kgf / cm ² using a low pressure transfer molding machine, (Length of idle motion) (unit: inch) was measured. The higher the measured value, the better the fluidity.

(2) High temperature modulus: The epoxy resin composition was cured at a mold temperature of 175 ° C ± 5 ° C, an injection pressure of 1000 psi ± 200psi and a curing time of 120 seconds using a transfer molding machine to prepare a specimen (length x width x thickness x 20 mm x 13 mm x 1.6 mm). The specimens were post-cured for 2 hours in a hot air drier at 175 ° C ± 5 ° C and then measured with a dynamic mechanical analyzer (DMA) using Q8000 (TA). In the measurement of the modulus, the temperature raising rate was increased from -10 ° C to 300 ° C at a rate of 5 ° C / minute, and a value at 260 ° C was obtained as a storage modulus.

(3) Reliability: A dummy chip was molded in an epoxy resin composition at 175 ° C on a PCB to obtain a specimen. The obtained specimens were post-cured (PMC) at 175 ° C for 4 hours. Thereafter, IR reflow was performed according to the following individual conditions after standing for 6 hours at 121 ° C, 100% RH and 2 atm under PCT (pressure cooker test) conditions. Ultrasonic analysis of the specimens completed until the IR reflow process for each of the five conditions shown in the following Table 3 was performed using a scanning acoustic tomography (SAT) facility. The reliability was evaluated by the lowest temperature at which peeling occurred (IR reflow Max temperature for each condition).

Condition 0: 270 to 275 ° C, Max 278 ° C Condition 1: 275 to 280 ° C, Max 283 ° C Condition 2: 280 to 285 DEG C, Max 287 DEG C Condition 3: 285 to 290 ° C, Max 293 ° C Condition 4: 290 to 295 DEG C, Max 298 DEG C

Evaluation items Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Flowability (inch) 39 38 45 35 41 32 High temperature modulus (MPa) 380 342 600 330 800 700 responsibility 293 ° C 298 ° C 283 DEG C 298 ° C 278 ° C 283 DEG C

As shown in Table 2, the epoxy resin composition of the present invention can improve the reliability of semiconductor devices and has excellent flowability. On the other hand, Comparative Example 1 had poor reliability and Comparative Example 2 had low fluidity.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (8)

An epoxy resin, a curing agent, an inorganic filler, and a curing accelerator,
Wherein the epoxy resin comprises a bisphenol epoxy resin modified with a polyurethane.
The epoxy resin composition for sealing a semiconductor device according to claim 1, wherein the polyurethane-modified bisphenol epoxy resin comprises an epoxy resin represented by the following formula (1)
≪ Formula 1 >

(Wherein, A is a residue of a polyurethane polymer,
R is a single bond or C (R ¹ R ² ), R ¹ and R ² are each independently hydrogen, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms, and R ¹ and R ² are Substituted or unsubstituted alicyclic rings having 6 to 20 carbon atoms,
n and m are each independently an integer of 1 to 100).
The epoxy resin composition for sealing a semiconductor element according to claim 1, wherein the bisphenol epoxy resin modified with polyurethane has a polar functional group.
The epoxy resin composition for sealing a semiconductor device according to claim 1, wherein the epoxy resin of Formula 1 is contained in an amount of 0.1 to 5 wt% of the composition for sealing a semiconductor device.
The epoxy resin composition for sealing a semiconductor element according to claim 1, wherein the epoxy resin further comprises a non-urethane-based epoxy resin.
The composition of claim 1, wherein the composition comprises
0.5 to 20% by weight of the epoxy resin,
0.1 to 15% by weight of the curing agent,
From 70% to 95% by weight of the inorganic filler,
And 0.01 to 5% by weight of the curing accelerator.
The epoxy resin composition for sealing a semiconductor element according to claim 1, wherein the epoxy resin composition further comprises at least one of a coupling agent, a releasing agent and a colorant.
A semiconductor device sealed by using the epoxy resin composition for sealing a semiconductor element according to any one of claims 1 to 7.