JP2022542694A - epoxy resin composition - Google Patents

Abstract

TECHNICAL FIELD The present invention relates to an epoxy resin composition applicable to high temperature drive power semiconductor encapsulants.

Description

TECHNICAL FIELD The present invention relates to an epoxy resin composition applicable to high temperature drive power semiconductor encapsulants.

As the performance of power semiconductors increases, the operating temperature rises, so high heat resistance is required for the materials that make up the devices. Among them, the material of the encapsulant for encapsulating the semiconductor device is particularly required to have high heat resistance. Recently, the demand for a semiconductor encapsulant having a high glass transition temperature (Tg) is increasing.

Conventionally, an epoxy resin composition for semiconductor encapsulation, in which an ortho cresol novolac type epoxy resin and a phenolic curing agent are used in combination, has been applied. However, there is a limit to the increase in the glass transition temperature.

In order to achieve a higher glass transition temperature, Korean Patent No. 10-0861324 applied an epoxy resin having a condensed cyclic polycyclic structure such as a naphthalene or anthracene structure. However, since the condensed cyclic epoxy resin has a high melt viscosity or a high softening point, the filler content cannot be set high, so it is vulnerable to heat deformation and moisture penetration, and is vulnerable to cracks after curing. . In addition, it has the disadvantage of insufficient electrical properties at the required high operating temperature. As another example, Korean Patent Publication No. 2014-0123065 discloses a technique of applying a biphenyl type resin to ensure high heat resistance by optimizing the skeleton density of the resin. However, such biphenyl-type resins generally have a disadvantage of poor dielectric properties.

In addition, a method of realizing a high glass transition temperature and excellent electrical properties by using an acid anhydride-based resin as a curing agent has also been proposed. However, acid anhydride-based resins having a high glass transition temperature have a high melting point, making it difficult to apply to a general epoxy resin encapsulant manufacturing process, and the high melt viscosity prevents a high filler content. Therefore, it is vulnerable to thermal deformation and moisture penetration at high operating temperatures and to cracks after curing.

As described above, the development of a semiconductor encapsulant having a high glass transition temperature continues, but such an encapsulant has a problem of being vulnerable to cracks due to its high elastic modulus. In particular, high-performance power semiconductors that operate at high temperatures are subject to high internal thermal stress due to expansion and contraction due to rapid temperature changes. delamination or cracks. In order to solve such problems, semiconductor sealing materials are required to have a low coefficient of thermal expansion and a low modulus of elasticity. In particular, devices based on silicon carbide (SiC) and gallium nitride (GaN), which are new materials that have advantages such as higher withstand voltage, higher current, and high temperature operation than devices based on silicon (Si), which are currently mainstream, are prone to cracking. It is more vulnerable to thermal expansion, so a low coefficient of thermal expansion and a low elastic modulus are further required.

Therefore, there is a demand for the development of an epoxy resin composition that has high heat resistance, a high filler content, a low coefficient of thermal expansion and a low elastic modulus, and excellent electrical properties at high temperatures. ing.

The present invention provides an epoxy resin composition having high heat resistance, low coefficient of thermal expansion, low high-temperature elastic modulus and excellent high-temperature electrical properties, which can be used as an encapsulant material for high-temperature drive power semiconductors.

The present invention provides an epoxy resin composition comprising a fluorene-containing epoxy resin, a curing agent, a filler and a curing accelerator.

The present invention also provides a semiconductor device encapsulated using the epoxy resin composition described above.

The epoxy resin composition according to the present invention has high heat resistance, low coefficient of thermal expansion and low high-temperature elastic modulus, can contain high filler content, and exhibits excellent electrical properties at high temperatures. The epoxy resin composition of the present invention can contain a filler in a high content of 80% or more, and may have a glass transition temperature of 200° C. or more, which is 180° C., which is the temperature at which a general semiconductor encapsulant is used. Excellent continuous workability below. Accordingly, the epoxy resin composition of the present invention is suitable for application as an encapsulant for high temperature drive power semiconductors.

The present invention will be described in detail below. However, it is not limited only by the following contents, and each component may be variously modified or selectively mixed as needed. Therefore, it should be understood to include all modifications, equivalents or alternatives falling within the spirit and scope of the invention.

<Epoxy resin composition>
The epoxy resin composition according to the present invention is an epoxy resin composition for semiconductor encapsulant (EMC: Epoxy Molding Compound), and includes a fluorene-containing epoxy resin, a curing agent, a curing accelerator and a filler. In addition, if necessary, one or more additives commonly used in the art, such as coupling agents, colorants, release agents, modifiers, flame retardants, and stress reducing agents, may be further included.

The composition of the epoxy resin composition will be specifically described below.

Epoxy Resin Fluorene-Containing Epoxy Resin The epoxy resin composition according to the present invention comprises a fluorene-containing epoxy resin. The method for producing the fluorene-containing epoxy resin is not particularly limited, and for example, it can be produced by reacting an epoxy resin or epichlorohydrin with a fluorene-containing compound. Said reaction may be carried out in the presence of a catalyst or in a suitable solvent.

The epoxy resin is not particularly limited as long as it is a common epoxy resin known in the art. Non-limiting examples of epoxy resins that can be used include bisphenol A type epoxy resins, cresol novolac type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, naphthalene type epoxy resins, anthracene epoxy resins, biphenyl type epoxies. resins, tetramethylbiphenyl type epoxy resins, phenol novolac type epoxy resins, bisphenol A novolac type epoxy resins, bisphenol S novolac type epoxy resins, biphenyl novolac type epoxy resins, naphthol novolac type epoxy resins, naphthol phenol cocondensation novolac type epoxy resins, Naphthol cresol cocondensed novolac type epoxy resin, aromatic hydrocarbon formaldehyde resin Modified phenol resin type epoxy resin, triphenylmethane type epoxy resin, tetraphenylethane type epoxy resin, dicyclopentadiene type epoxy resin, dicyclopentadiene phenol addition reaction type One or more of epoxy resins, phenol aralkyl type epoxy resins, polyfunctional phenolic epoxy resins, and naphthol aralkyl type epoxy resins may be used, but are not necessarily limited to these.

Although the type of the fluorene-containing compound is not particularly limited, for example, it may be a compound having the structure of Chemical Formula 1 below.

In the above formula,
each R1 is independently a cyano group, a halogen atom or an alkyl group having 1 to 6 carbon atoms,
each R2 is independently an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms or a cycloalkyl group having 6 to 10 carbon atoms;
each R3 is independently an alkylene group having 1 to 4 carbon atoms,
each l is independently an integer of 0 to 4;
m is each independently an integer of 0 to 4,
n is each independently an integer of 0 to 5,
o are each independently an integer of 1 to 3,
n+o is an integer of 5 or less.

The fluorene-containing compound is, for example, 9,9-bis[4-(2-hydroxypropoxy)-3-methylphenyl)fluorene, 9,9-bis[4-(2-hydroxypropoxy)-3-ethylphenyl)fluorene , 9,9-bis[4-(2-hydroxypropoxy)-3-propylphenyl)fluorene, 9,9-bis[4-(2-hydroxypropoxy)-3-butylphenyl)fluorene, 9,9-bis (2-hydroxypropoxy-3-phenylphenyl)fluorene, 9,9-bis(2-hydroxypropoxy-benzylphenyl)fluorene, 9,9-bis(2-hydroxypropoxy-tolylphenyl)fluorene, 9,9-bis (2-hydroxypropoxy-silylphenyl)fluorene, 9,9-bis[4-{2-(2-hydroxypropoxy)propoxy}-3-methylphenyl]fluorene, 9,9-bis[4-{2-( 2-hydroxypropoxy)propoxy}-3-ethylphenyl]fluorene, 9,9-bis[4-{2-(2-hydroxypropoxy)propoxy}-3-propylphenyl]fluorene, 9,9-bis[4- {2-(2-hydroxypropoxy)propoxy}-3-butylphenyl]fluorene, 9,9-bis[2-(2-hydroxypropoxy)propoxy-3-phenylphenyl]fluorene, 9,9-bis[2- (2-hydroxypropoxy)propoxy-3-benzylphenyl]fluorene, 9,9-bis[2-(2-hydroxypropoxy)propoxy-3-tolylphenyl]fluorene, 9,9-bis[2-(2-hydroxy propoxy)propoxy-3-silylphenyl]fluorene, 9,9-bis-(3′,4′-dihydroxyphenyl)-fluorene, 9,9-bis-(2′,4′-dihydroxyphenyl)-fluorene, 9 ,9-bis-(3′,5′-dihydroxyphenyl)-fluorene, 9,9-bis-(2′,3′-dihydroxyphenyl)-fluorene, 9,9-bis-(2′,6′- dihydroxyphenyl)-fluorene, 9,9-bis-(2′,5′-dihydroxyphenyl)-fluorene, 4-4′-(9-fluorenylidene)diphenol at least one selected from the group consisting of good too.

The type of solvent used for the reaction of the epoxy resin and the fluorene-containing compound is not particularly limited, and examples include ether solvents such as dimethyl ether, diethyl ether, and tetrahydrofuran; halogen solvents such as methylene chloride, chloroform, and carbon tetrachloride; At least one of aromatic hydrocarbon solvents such as benzene, toluene and xylene; and lower alcohols such as methanol and ethanol can be used.

The catalyst used for the reaction of the epoxy resin and the fluorene-containing compound may be one selected from, for example, metal hydroxides, metal carbonates, amines, metal carboxylates, or a mixture thereof.

As an example, the fluorene-containing epoxy resin of the present invention includes an epoxy resin represented by Formula 2 below.

In the above formula,
R1 and R2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms,
n is an integer from 2 to 10;

The alkyl group having 1 to 6 carbon atoms means a linear or branched hydrocarbon having 1 to 6 carbon atoms. Examples include, but are not limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, n-hexyl and the like.

The alkoxy group having 1 to 6 carbon atoms means a linear or branched alkoxy group having 1 to 6 carbon atoms. Examples include, but are not limited to, methoxy, ethoxy, n-propaneoxy, and the like.

R1 and R2 may be the same or different, and each independently represents hydrogen, an alkyl group such as a methyl group, an ethyl group, a propyl group, a methoxy group, an ethoxy group, a propoxy group, or the like. may be an alkoxy group.

In the present invention, the fluorene-containing epoxy resin may further include an epoxy resin represented by Formula 3 below, in addition to the epoxy resin represented by Formula 2 above. When an epoxy resin represented by Formula 3 below is mixed, the thermal expansion coefficient and high-temperature elastic modulus of the epoxy resin composition can be further reduced.

In the above formula,
R1 and R2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms.

The alkyl group having 1 to 6 carbon atoms means a linear or branched hydrocarbon having 1 to 6 carbon atoms. Examples include, but are not limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, n-hexyl and the like.

The alkoxy group having 1 to 6 carbon atoms means a linear or branched alkoxy group having 1 to 6 carbon atoms. Examples include, but are not limited to, methoxy, ethoxy, n-propaneoxy, and the like.

R1 and R2 may be the same or different, and each independently represents hydrogen, an alkyl group such as a methyl group, an ethyl group, a propyl group, a methoxy group, an ethoxy group, a propoxy group, or the like. may be an alkoxy group.

The epoxy resin represented by Formula 3 may be represented by Formula 3a below.

The fluorene-containing epoxy resin may have a melt viscosity at 150° C. of 3 poise or less, such as 1 to 3 poise, measured using an ICI viscometer (Research Equip., TW 5NX). The softening point of the fluorene-containing epoxy resin may be 100°C or less, for example 50-100°C. Since the fluorene-containing epoxy resin has a low melt viscosity and a softening point within the above range, the filler content is high, for example, 80% by weight or more, such as 85 to 90% by weight, based on the total weight of the epoxy resin composition. It can have excellent kneadability even though it contains .

The epoxy equivalent weight (EEW) of the fluorene-containing epoxy resin is not particularly limited. The epoxy equivalent weight of the fluorene-containing epoxy resin may be, for example, 150-400 g/eq, and as another example, 200-300 g/eq.

The fluorene-containing epoxy resin may be included in an amount of 30-100% by weight based on the total weight of the epoxy resin. If the fluorene-containing epoxy resin is contained in an amount of less than 30% by weight, a sufficiently high glass transition temperature cannot be ensured, or a low coefficient of thermal expansion and a low modulus of elasticity at high temperatures cannot be ensured. In addition, when mixed with other epoxy resins having a high glass transition temperature such as naphthalene type or anthracene type, it is difficult to set a high filler content, and it is difficult to achieve a dielectric constant of 5.5 or less at 200° C. after curing.

When the epoxy resin of the present invention contains the epoxy resin represented by Formula 3, the mixing ratio of the epoxy resin represented by Formula 2 and the epoxy resin represented by Formula 3 is 1:0.1-1. 5 weight ratios, such as 1:0.8 to 1.2 weight ratios. When the epoxy resin represented by Chemical Formula 3 is mixed in the above ratio, the thermal expansion coefficient and high-temperature elastic modulus of the epoxy resin composition can be further reduced.

Epoxy resin having a non-condensed cyclic polycyclic structure and at least three functional groups The epoxy resin composition of the present invention is an epoxy resin having a non-condensed cyclic polycyclic structure and at least three functional groups in addition to the fluorene-containing epoxy resin. may further include

When the non-condensed cyclic polycyclic structure and the epoxy resin having at least three functional groups are used in combination, the melt viscosity of the epoxy resin composition can be reduced and the glass transition temperature can be further increased. The epoxy resin having a non-condensed cyclic polycyclic structure and at least three functional groups may be represented by Formula 4 below.

In the above formula,
R1 to R3 are each independently an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms,
R4 to R19 are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms.

The epoxy resin represented by Formula 4 may be represented by Formula 4a below.

In the above formula,
R1 to R3 are each independently an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms.

The alkyl group having 1 to 6 carbon atoms means a linear or branched hydrocarbon having 1 to 6 carbon atoms. Examples include, but are not limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, n-hexyl and the like.

The alkoxy group having 1 to 6 carbon atoms means a linear or branched alkoxy group having 1 to 6 carbon atoms. Examples include, but are not limited to, methoxy, ethoxy, n-propaneoxy, and the like.

R1 to R3 may be the same or different and each independently represents an alkyl group such as a methyl group, an ethyl group or a propyl group, or an alkoxy group such as a methoxy group, an ethoxy group or a propoxy group. may

When the epoxy resin of the present invention contains the epoxy resin represented by Formula 4, the mixing ratio of the epoxy resin represented by Formula 2 and the epoxy resin represented by Formula 4 is 1:0.1-1. .5 weight ratio, such as 1:0.8 to 1.2 weight ratio. When the epoxy resin represented by Chemical Formula 4 is mixed in the above ratio, the melt viscosity of the epoxy resin composition can be reduced and the glass transition temperature can be further increased.

As still another example, when the epoxy resin of the present invention includes the epoxy resin represented by the chemical formula 4, the epoxy resin represented by the chemical formula 2, the epoxy resin represented by the chemical formula 3, and the epoxy resin represented by the chemical formula 4 The mixing ratio of the epoxy resin is 1:0.1-1.5:0.1-1.5 weight ratio, for example, 1:0.8-1.2:0.8-1.2 weight ratio. good too. When the three types of epoxy resins are mixed in the above ratio, the melt viscosity of the epoxy resin composition can be reduced, the glass transition temperature can be increased, and the thermal expansion coefficient and high-temperature elastic modulus can be further reduced.

The epoxy resin composition of the present invention may further contain epoxy resins commonly used in the field in addition to the epoxy resins described above. For example, polymers or oligomers containing at least two epoxy groups in one molecule and polymers or oligomers produced by ring-opening reaction of the epoxy groups can be used. Examples include bisphenol A-type, cycloaliphatic, linear aliphatic, (ortho)cresol novolac-type, naphthol novolac-type, biphenyl-type, polyfunctional, naphthalene-type, anthracene-type and dicyclopentadiene-type epoxy resins alone or It can be used as a mixture of two or more types, and in order to achieve particularly high heat resistance, it may contain at least one of (ortho)cresol novolac type epoxy resin and naphthalene type epoxy resin, but it must be limited to these. is not. The epoxy resin may have an epoxy equivalent weight of 120-280 g/eq and a softening point of 50-120°C.

The epoxy resin may be included in an amount of 2-15% by weight, such as 5-10% by weight, based on the total weight of the epoxy resin composition. If the content of the epoxy resin is less than 2% by weight, adhesiveness, electrical insulation, fluidity and moldability may be deteriorated. However, increased moisture absorption can lead to poor semiconductor reliability, and reduced relative filler content can lead to reduced strength.

Curing Agent In the present invention, the curing agent is a component that reacts with the epoxy resin, which is the main resin, to promote curing of the composition, and includes a benzoxazine-based compound. The benzoxazine-based compound may be represented by Chemical Formula 5 below.

In the above formula,
X is an alkylene group having 1 to 10 carbon atoms,
R20 to R27 are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms.

The softening point of the benzoxazine-based resin represented by Chemical Formula 5 may be 100°C or less, for example, 50 to 100°C.

The benzoxazine-based resin represented by Formula 5 may be represented by Formula 5a below.

The benzoxazine compound represented by Formula 5 may be included in an amount of 15-100% by weight based on the total weight of the curing agent. If the benzoxazine compound of Formula 5 is included in less than 15% by weight, a sufficiently high glass transition temperature may not be ensured.

When the benzoxazine compound represented by Formula 5 is used alone as a curing agent, the compounding ratio with the epoxy resin is such that the active group in the benzoxazine capable of reacting with one equivalent of the epoxy group in the entire epoxy resin is The ratio may range from 0.5 to 1.1 equivalents, such as from 0.7 to 0.9 equivalents. If the active group of benzoxazine is less than 0.5 equivalent with respect to 1 equivalent of epoxy group, the curability is low, the continuous workability is low, and the strength of the cured product is low. On the other hand, if it exceeds 1.1 equivalents, the adhesive properties of the cured product will be low, the water resistance will be low, and the high temperature and high humidity reliability of the package (PKG) will be low.

In the present invention, the curing agent may further contain, in addition to the benzoxazine compound represented by Formula 5, a curing agent commonly used in semiconductor encapsulants. The curing agent to be further included is not particularly limited as long as it is a curing agent capable of reacting with the epoxy resin. Available.

As the phenol resin-based curing agent, those containing two or more phenolic hydroxy groups that react with the epoxy resin component in the molecular structure to promote curing can be used. Examples include phenol novolac resin, Zyloc resin, cresol novolac At least one or more polyhydric phenol compounds selected from the group consisting of resins, phenol alkyl resins, various novolac resins synthesized from bisphenol A, and dihydrobiphenyls can be used.

When both the benzoxazine compound and the phenolic resin curing agent are used as the curing agent, the compounding ratio with the epoxy resin is such that there are 0 active groups in the curing agent that can react with one equivalent of epoxy groups in the entire epoxy resin. The ratio may range from 0.7 to 1.2 equivalents, such as from 0.8 to 1.1 equivalents. If the active group of the curing agent is less than 0.7 equivalents per equivalent of epoxy groups, the curing speed of the epoxy resin composition will be delayed, and if it exceeds 1.2 equivalents, the strength of the cured product after final curing will decrease. do. Further, if the equivalent weight is out of the above range, high-temperature thermal decomposition may occur due to unreacted epoxy groups or curing agents.

The curing agent may be included in an amount of 1-15% by weight, such as 2-10% by weight, based on the total weight of the epoxy resin composition. If the content of the curing agent is less than 1% by weight, problems may occur in curability and moldability. The strength of the cured product becomes low.

Filler In the present invention, the filler is a component for improving the strength of the encapsulating material and reducing the amount of moisture absorption, and fillers applicable in the relevant field can be used without limitation. For example, fillers such as silica, silica nitride, alumina, aluminum nitride, and boron nitride can be used alone or in combination of two or more, but are not necessarily limited to these. Also, the shape of the filler is not particularly limited, and both angular and spherical fillers can be used.

The average particle size of the filler is not particularly limited, but may be, for example, 5 to 30 μm. When considering in-mold filling properties, the maximum particle size of the filler may be 180 μm or less, for example 150 μm or less.

The filler may be included in an amount of 80% by weight or more, such as 80-90% by weight, based on the total weight of the epoxy resin composition. For example, based on the flowability of 30 inches or more, the filler may be contained in an amount of 80% by weight or more, for example, 80 to 88% by weight. , up to 90% by weight, for example 88-90% by weight. If the content of the filler is less than 80% by weight, the strength may decrease due to an increase in moisture absorption, and adhesion may be poor after the reflow soldering process. , increased viscosity and decreased flowability can lead to poor moldability.

Curing Accelerator The curing accelerator of the present invention can be used without any particular limitation as long as it is commonly used in the field concerned. For example, imidazole compounds such as 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, amine compounds such as triethylamine, tributylamine, benzyldimethylamine, 2-(dimethylaminomethyl)phenol, 2,4 ,6-tris(dimethylaminomethyl)phenol, 1,8-diazabicyclo(5,4,0)undec-7-ene and other tertiary amine compounds and phenylphosphine, diphenylphosphine, triphenylphosphine, tributylphosphine, tri( Organic phosphine compounds such as p-methylphenyl)phosphine can be used alone or in combination of two or more, but are not necessarily limited to these.

The content of the curing accelerator may be 0.05 to 1.0 wt%, for example 0.05 to 0.5 wt%, based on the total weight of the epoxy resin composition. If the content of the curing accelerator is less than 0.05% by weight, curability may be deteriorated.

Additives The epoxy resin composition according to the present invention may further contain additives generally used in epoxy resin compositions for semiconductor encapsulation within the scope of the purpose of the present invention. Non-limiting examples of additives that can be used include coupling agents, colorants, mold release agents, modifiers, flame retardants, stress reducing agents, or mixtures of two or more thereof.

Since the epoxy resin composition of the present invention has a high filler content, it can exhibit excellent flame retardancy by itself, and may further contain a flame retardant to further improve flame retardancy. . As flame retardants, metal hydroxides; phosphorus- and nitrogen-containing organic compounds (e.g., resorcinol diphosphate, phosphate, phenoxyphosphazene, melamine cyanurate and phenol melamine resin), etc. can be used singly or in combination of two or more. , but not necessarily limited to these.

In addition, the epoxy resin composition of the present invention may further contain a coupling agent such as an epoxysilane-based, aminosilane-based, mercaptosilane-based, acrylsilane-based, or vinylsilane-based coupling agent for stable dispersion of organic matter and inorganic matter.

In addition, the epoxy resin composition of the present invention may contain coloring agents such as carbon black and red iron oxide, hydrotalcite-based ion scavengers, long-chain fatty acids, metal salts of long-chain fatty acids, paraffin wax, carnauba wax, polyethylene wax, and the like. It may further contain one or more additives selected from release agents, modifiers, and stress reducing agents such as modified silicone resins and modified polybutadiene.

The additive can be added appropriately within the range of content known in the art, and for example, it may be contained in an amount of 0.05 to 5% by weight based on the total weight of the epoxy resin composition. , but not limited to.

The epoxy resin composition according to the present invention can be produced by a conventional method known in the art, such as a melt-kneading method using a Banbury mixer, kneader, rolls, single-screw or twin-screw extruder and co-kneader. For example, after uniformly mixing each component as described above, the mixture is melt-kneaded at a temperature of 80 to 130° C. using a heat kneader, cooled to room temperature, pulverized into a powder state, An epoxy resin composition can be obtained by blending.

The epoxy resin composition according to the present invention has high heat resistance, low coefficient of thermal expansion and low high-temperature elastic modulus, and may contain a high content of fillers (eg, 80% by weight or more). The epoxy resin composition of the present invention may have a glass transition temperature of 200° C. or higher, and has excellent fluidity (175° C., 70 kgf/cm ² ) of 25 inches or higher, for example, 30 to 50 inches, and is suitable for general semiconductors. Excellent continuous workability can be exhibited at 180° C. or less, which is the working temperature of the encapsulant. The epoxy resin composition may also exhibit excellent electrical properties at high temperatures, for example, a dielectric constant at 200° C. of 5.5 or less, eg, 4.0 to 5.5 after curing. Further, the epoxy resin composition of the present invention may have an elastic modulus (260° C.) of 1.5 Gpa or less, for example 1.2 Gpa or less.

Accordingly, the epoxy resin composition of the present invention is suitable for application as an encapsulant for high temperature drive power semiconductors.

<Semiconductor element>
The present invention provides a semiconductor device encapsulated using the epoxy resin composition described above.

The semiconductor devices may be transistors, diodes, microprocessors, semiconductor memories, power semiconductors, and the like.

A method for encapsulating a semiconductor element using the epoxy resin composition of the present invention can be carried out by a molding method such as transfer molding, compression molding, injection molding, or the like, which is common in the field concerned.

EXAMPLES The present invention will now be described more specifically based on examples. However, the following examples are merely for helping understanding of the present invention, and the scope of the present invention is not limited to the examples in any way.

[Example 1-15]
Each component was blended according to the composition shown in Table 1 below, melt-kneaded at a temperature of 100 to 130° C. using a kneader, cooled to room temperature, pulverized into a powder state, and blended. Epoxy resin compositions of Examples 1 to 15 were obtained through the steps (unit: % by weight).

[Comparative Example 1-4]
Epoxy resin compositions of Comparative Examples 1 to 4 were obtained in the same manner as in Examples, except for the compositions shown in Table 2 below (unit: % by weight).

A-1: Epoxy resin of chemical formula 2 (R1 = R2 = hydrogen group, n = 4) (softening point: 95 ° C., epoxy equivalent: 260 g / eq, melt viscosity (150 ° C.): 3 poise)
A-2: Epoxy resin of chemical formula 2 (R1 = R2 = methyl group, n = 7) (softening point: 92 ° C., epoxy equivalent: 266 g / eq, melt viscosity (150 ° C.): 2.8 poise)
A-3: Epoxy resin of chemical formula 4 (R1 = R2 = R3 = methyl group) (softening point: 65 ° C., epoxy equivalent: 230 g / eq, melt viscosity (150 ° C.): 2 poise)
A-4: Epoxy resin of chemical formula 3 (softening point: 65 ° C., epoxy equivalent: 250 g / eq, melt viscosity (150 ° C.): 2.5 poise)
A-5: Naphthalene type epoxy resin (softening point: 75 ° C., epoxy equivalent: 203 g / eq, melt viscosity (150 ° C.): 4 poise)
B-1: benzoxazine of chemical formula 5a (softening point: 78 ° C.)
B-2: Polyfunctional phenol resin (softening point: 83 ° C.)
B-3: Phenol novolac resin (softening point: 84 ° C.)
C: Silica (SiO2) (average particle size: 19.9 μm)
D: imidazole type (2MZ, Shikoku Chemical)
E-1: Carbon black E-2: Carnauba wax (CAR-WAX, KAHL GMBH & CO. KG)
E-3: Epoxysilane (S-510, CHISSO Corporation)
E-4: aluminum hydroxide

[Experimental example: physical property evaluation]
The physical properties of the epoxy resin compositions prepared in Examples 1-15 and Comparative Examples 1-4 were measured as follows, and the results are shown in Tables 3 and 4 below. Test pieces for physical property evaluation were molded by transfer molding the epoxy resin composition powders produced in Examples and Comparative Examples at 175° C. for 120 seconds, and post-cured at 190° C. for 6 hours. manufactured by

spiral flow
The flowability of the epoxy resin compositions prepared according to each example and comparative example was measured using a transfer molding press at 175° C. and 70 kgf/cm ² using an evaluation mold according to EMMI-1-66.

Glass transition temperature (Tg)/coefficient of thermal expansion (CTE)
Test pieces of the same size were molded and measured using a TMA (Thermo-mechanical Analyzer). The temperature was measured from room temperature to 300° C. at a heating rate of 10° C./min using 'TMA Q400' manufactured by TA, and the glass transition temperature was obtained using the onset point technique. Also, the thermal expansion coefficient was measured on the basis of the 80 to 120°C interval.

Dielectric constant (Dk)
Dielectric constants were measured from 30° C. to 240° C. after post-curing using circular specimens with a diameter of 30 mm and a thickness of 2 mm. The measurement conditions were 1 Hz and AC 1.5V.

Elastic modulus Test pieces of the same size were molded and measured using a DMA (Dynamic-mechanical Analyzer). Storage modulus measured from room temperature to 300° C. at a heating rate of 10° C./min using Perkin Elmer's 'DMA8000' was used.

As can be seen from the results in Tables 3 and 4, the epoxy resin compositions according to the examples exhibited generally superior physical properties compared to the epoxy resin compositions of the comparative examples. Specifically, the epoxy resin composition of the example according to the present invention has a high glass transition temperature after curing, and at the same time exhibits excellent heat resistance, a low coefficient of thermal expansion and a high-temperature elastic modulus, and exhibits excellent electrical properties at high temperatures. can be confirmed.

The epoxy resin composition according to the present invention has high heat resistance, low coefficient of thermal expansion and low high-temperature elastic modulus, can contain high filler content, and exhibits excellent electrical properties at high temperatures. The epoxy resin composition of the present invention can contain a filler in a high content of 80% or more, and may have a glass transition temperature of 200° C. or more, which is 180° C., which is the temperature at which a general semiconductor encapsulant is used. Excellent continuous workability below. Accordingly, the epoxy resin composition of the present invention is suitable for application as an encapsulant for high temperature drive power semiconductors.

Claims (9)

An epoxy resin composition comprising an epoxy resin, a curing agent, a filler and a curing accelerator,
The epoxy resin comprises a fluorene-containing epoxy resin,
The fluorene-containing epoxy resin is produced by reacting an epoxy resin or epichlorohydrin with a fluorene-containing compound,
The fluorene compound is an epoxy resin composition represented by the following chemical formula 1:

In the above formula,
each R1 is independently a cyano group, a halogen atom or an alkyl group having 1 to 6 carbon atoms,
each R2 is independently an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms or a cycloalkyl group having 6 to 10 carbon atoms;
each R3 is independently an alkylene group having 1 to 4 carbon atoms,
each l is independently an integer of 0 to 4;
m is each independently an integer of 0 to 4,
n is each independently an integer of 0 to 5,
o are each independently an integer of 1 to 3,
n+o is an integer of 5 or less. The epoxy resin composition according to claim 1, wherein the fluorene-containing epoxy resin comprises an epoxy resin represented by the following chemical formula 2:

In the above formula,
R1 and R2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms,
n is an integer from 2 to 10; The epoxy resin composition according to claim 2, wherein the fluorene-containing epoxy resin further comprises an epoxy resin represented by Formula 3 below:

In the above formula,
R1 and R2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms. 2. The fluorene-containing epoxy resin according to claim 1, wherein the melt viscosity at 150° C. is 3 poise or less, the softening point is 50-100° C., and the epoxy equivalent is 150-400 g/eq. Epoxy resin composition. The epoxy resin composition according to claim 1, comprising 30 to 100% by weight of the fluorene-containing epoxy resin based on the total weight of the epoxy resin. The epoxy resin composition according to claim 1, wherein the epoxy resin further comprises an epoxy resin represented by Formula 4 below:

In the above formula,
R1 to R3 are each independently an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms,
R4 to R19 are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms. The epoxy resin further includes an epoxy resin represented by the following chemical formula 4,
The mixing ratio of the epoxy resin represented by the chemical formula 2, the epoxy resin represented by the chemical formula 3 and the epoxy resin represented by the following chemical formula 4 is 1:0.1-1.5:0.1-1. Epoxy resin composition according to claim 3, in a 5 weight ratio:

In the above formula,
R1 to R3 are each independently an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms,
R4 to R19 are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms. It has a glass transition temperature of 200°C or higher, a dielectric constant at 200°C after curing of 5.5 or lower, a fluidity (175°C, 70 kgf/cm ² ) of 25 inches or higher, and an elastic modulus (260°C) of The epoxy resin composition according to claim 1, which is 1.5 Gpa or less. A semiconductor device encapsulated with the epoxy resin composition according to claim 1 .