KR20230164858A - Composition for Encapsulating Semiconductor Device and Semiconductor Device Encapsulated Using the Same - Google Patents

Abstract

The present invention provides a composition for sealing semiconductor devices containing a trifunctional or higher epoxy monomer and a curing agent, and a semiconductor device sealed using the same. The composition for encapsulating semiconductor devices according to the present invention can form a dense network by using a trifunctional or higher epoxy monomer, thereby not only increasing the glass transition temperature of the composition for encapsulating semiconductor devices, but also increasing thermal conductivity.

Description

Composition for encapsulating semiconductor devices and semiconductor devices sealed using the same {Composition for Encapsulating Semiconductor Device and Semiconductor Device Encapsulated Using the Same}

The present invention relates to a composition for sealing semiconductor devices and a semiconductor device sealed using the same. More specifically, the present invention relates to a composition for sealing semiconductor devices that can not only increase the glass transition temperature of the composition for sealing semiconductor devices, but also increase thermal conductivity. It relates to a composition and a semiconductor device sealed using the same.

Semiconductor packaging is a technology that mounts semiconductor chips so that they can operate as electrical and electronic components. It supplies the necessary power to semiconductor devices, connects signals between semiconductor devices, emits heat generated from semiconductor devices, and uses natural, chemical, and It serves to protect the device from changes in the thermal environment.

Recently, with miniaturization and high integration, there is concern about heat generation inside semiconductor packages. Since heat generation may cause performance deterioration of electric components or electronic components having a semiconductor package, high thermal conductivity is required for members used in the semiconductor package.

Republic of Korea Patent Publication No. 10-2020-0103682 contains an epoxy resin, a curing agent, and an inorganic filler, the particle size distribution of the inorganic filler has at least three peaks, and the inorganic filler includes alumina with a particle diameter of 1 μm or less. A sealing composition having excellent fluidity and high thermal conductivity is disclosed.

However, unlike inorganic fillers that have relatively fixed thermal conductivity in compositions for encapsulating semiconductor devices, the thermal conductivity of epoxy resin has a significant impact on the thermal conductivity of the encapsulant.

Thermosetting epoxy resins used to seal semiconductor devices have lower thermal conductivity and lower thermal stability at high temperatures than inorganic fillers.

Accordingly, there is a need for the development of a method that can prevent a decrease in thermal conductivity due to epoxy resin and further improve thermal conductivity in compositions for sealing semiconductor devices.

In addition, there is a need to develop a composition for sealing semiconductor devices that can increase the glass transition temperature in order to sufficiently secure heat resistance and warping inhibition properties.

Republic of Korea Patent Publication No. 10-2020-0103682

One object of the present invention is to provide a composition for encapsulating semiconductor devices that can not only increase the glass transition temperature of the composition for encapsulating semiconductor devices, but also increase thermal conductivity.

Another object of the present invention is to provide a semiconductor device sealed using the epoxy resin composition.

On the other hand, the present invention provides a composition for sealing semiconductor devices including a trifunctional or higher epoxy monomer and a curing agent.

In one embodiment of the present invention, the trifunctional or higher epoxy monomer may include a compound represented by the following formula (1).

[Formula 1]

In the above equation,

R is an arylene group,

n is an integer from 3 to 8.

In one embodiment of the present invention, the trifunctional or higher epoxy monomer may be one or more selected from compounds represented by the following formulas 1-1 to 1-2.

[Formula 1-1]

[Formula 1-2]

In one embodiment of the present invention, the molecular weight of the trifunctional or higher epoxy monomer may be 300 to 1,000.

The composition for encapsulating a semiconductor device according to an embodiment of the present invention may further include one or more selected from the group consisting of an inorganic filler, a curing accelerator, a silane coupling agent, a mold release agent, and a colorant.

On the other hand, the present invention provides a semiconductor device sealed using the composition for sealing a semiconductor device.

The composition for encapsulating semiconductor devices according to the present invention can form a dense network by using a trifunctional or higher epoxy monomer, thereby not only increasing the glass transition temperature of the composition for encapsulating semiconductor devices, but also increasing thermal conductivity.

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

One embodiment of the present invention relates to a composition for encapsulating semiconductor devices containing a trifunctional or higher epoxy monomer (A) and a curing agent (B).

In the present invention, unlike general polymer or oligomer type epoxy resins used for sealing semiconductor devices, the use of trifunctional or higher epoxy monomers enables the formation of a dense network, which not only increases the glass transition temperature of the composition for sealing semiconductor devices. In addition, thermal conductivity can also be increased.

The composition for encapsulating semiconductor devices according to an embodiment of the present invention may have a glass transition temperature of 130°C or higher, and preferably 155°C or higher, even under conditions that do not contain an inorganic filler.

The composition for encapsulating semiconductor devices according to an embodiment of the present invention may have a thermal conductivity of its cured product of 0.2 W/m·K or more, for example, 0.23 W/m·K or more even under conditions that do not contain an inorganic filler.

Trifunctional or higher epoxy monomer (A)

In one embodiment of the present invention, the trifunctional or higher epoxy monomer (A) is an epoxy compound in the form of a monomer containing three or more epoxy groups in one molecule.

The trifunctional or higher epoxy monomer may have 3 to 8 epoxy groups, for example, 3 to 4 epoxy groups. The greater the number of epoxy groups, the more advantageous it is to form a dense network.

The trifunctional or higher epoxy monomer moves relatively freely within the composition compared to oligomers or polymers, enabling the formation of a dense network during curing, thereby improving the glass transition temperature of the composition for encapsulating semiconductor devices.

Preferably, the trifunctional or higher epoxy monomer may include an aromatic ring in the molecule to improve thermal conductivity through a structural alignment effect through pi-pi stacking.

In one embodiment of the present invention, the trifunctional or higher epoxy monomer may include a compound represented by the following formula (1).

[Formula 1]

In the above equation,

R is an arylene group,

n is an integer from 3 to 8.

Arylene groups used herein include both aromatic groups, heteroaromatic groups, and partially reduced derivatives thereof. The aromatic group is a simple or fused ring of 5 to 30 members, and the heteroaromatic group refers to an aromatic group containing one or more oxygen, sulfur, or nitrogen. Representative examples of arylene groups include phenylene, naphthylene, pyridinylene, furanylene, thiophenylene, indolylene, quinolinylene, and imidazolinylene ( Examples include, but are not limited to, imidazolinylene, oxazolylene, thiazolylene, tetrahydronaphthylene, triphenylmethane, and tetraphenylethane.

In one embodiment of the present invention, R may be triphenylmethane or tetraphenylethane, especially in terms of improving glass transition temperature and/or thermal conductivity.

In one embodiment of the invention, n may preferably be 3 to 4.

The trifunctional or higher epoxy monomer may be one or more selected from compounds represented by the following formulas 1-1 to 1-2.

[Formula 1-1]

[Formula 1-2]

The molecular weight of the trifunctional or higher epoxy monomer may be 300 to 1,000. If the molecular weight of the trifunctional or higher epoxy monomer is less than 300, thermal stability may decrease, and if it exceeds 1,000, moldability may decrease due to viscosity.

The trifunctional or higher epoxy monomer may be included in an amount of 1% to 90% by weight, preferably 1% to 70% by weight, based on 100% by weight of the total composition for encapsulating semiconductor devices. If the content of trifunctional or higher epoxy monomer is less than 1% by weight, curing may be difficult, and if it is more than 90% by weight, thermal properties may deteriorate.

Hardener (B)

In one embodiment of the present invention, the curing agent (B) may be any general curing agent used for encapsulating semiconductor devices without limitation, and specifically, a curing agent having two or more functional groups may be used.

For example, the curing agent may include a phenol-based curing agent, an amine-based curing agent, an acid anhydride-based curing agent, and a mercaptan-based curing agent. Among these, phenolic curing agents are preferable in terms of balance between flame resistance, moisture resistance, electrical properties, curability, storage stability, etc.

The phenol-based curing agent includes phenol novolak resin, cresol novolak resin, phenol, cresol, resocin, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, α-naphthol, β-naphthol, dihyde. A novolac resin obtained by condensing or co-condensing phenols such as roxinaphthalene with formaldehyde or ketones under an acidic catalyst, and a biphenylene skeleton synthesized from the above-mentioned phenols and dimethoxyparaxylene or bis(methoxymethyl)biphenyl. Phenol aralkyl resins such as those having a phenol aralkyl resin, phenol aralkyl resins having a phenylene skeleton, and phenol resins having a trisphenolmethane skeleton.

The amine-based curing agent includes aliphatic polyamines such as diethylenetriamine (DETA), metaxylenediamine (MXDA), and triethylenetetramine (TETA), diaminodiphenylmethane (DDM), and m-phenylenediamine ( In addition to aromatic polyamines such as MPDA) and diaminodiphenylsulfone (DDS), polyamine compounds containing dicyandiamide (DICY) and organic acid dihydrazide, etc. can be mentioned.

Examples of the acid anhydride-based curing agent include alicyclic acid anhydrides such as hexahydrophthalic anhydride (HHPA), methyltetrahydrophthalic anhydride (MTHPA) and maleic anhydride, trimellitic anhydride (TMA) and pyromellitic anhydride (PMDA). and aromatic acid anhydrides such as benzophenone tetracarboxylic acid (BTDA) and phthalic anhydride.

Examples of the mercaptan-based curing agent include trimethylolethane tris (3-mercaptobutyrate), trimethylolpropane tris (3-mercaptobutyrate), and the like.

In addition to this, isocyanate compounds such as isocyanate prepolymer and blocked isocyanate, and organic acids such as carboxylic acid-containing polyester resin.

The curing agent may be used alone or in combination of two or more of the above-mentioned curing agents.

The mixing ratio of the epoxy resin and curing agent can be adjusted according to the requirements for 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 about 0.95 to 3, preferably 1 to 2, and more preferably 1 to 1.75. When the mixing ratio of the epoxy resin and the curing agent satisfies the above range, excellent strength can be achieved after curing the epoxy resin composition.

The curing agent may be included in an amount of 1% to 90% by weight, preferably 1% to 40% by weight, based on 100% by weight of the total composition for encapsulating semiconductor devices. When the content of the curing agent satisfies the above range, the strength of the epoxy resin composition can be improved after curing.

Curing accelerator (C)

The composition for encapsulating a semiconductor device according to an embodiment of the present invention may further include a curing accelerator (C).

The curing accelerator is a substance that promotes the reaction between the epoxy resin and the curing agent, and may be one or more selected from the group consisting of tertiary amines, organic metal compounds, organic phosphorus compounds, imidazoles, and boron compounds.

Specific examples of the tertiary amine include benzyldimethylamine, triethanolamine, triethylenediamine, diethylaminoethanol, tri(dimethylaminomethyl)phenol, 2-2-(dimethylaminomethyl)phenol, 2,4,6- Tris(diaminomethyl)phenol, etc.

Specific examples of the organometallic compounds include zinc acetylacetonate, chromium acetylacetonate, and nickel acetylacetonate.

Specific examples of the organic phosphorus compounds include tris-4-methoxyphosphine, tetrabutylphosphonium bromide, tetraphenylphosphonium bromide, phenylphosphine, diphenylphosphine, triphenylphosphine, and triphenylphosphinetriphenyl. There are borane, triphenylphosphine-1,4-benzoquinone adducts, etc.

Specific examples of the imidazoles include 2-phenyl-4-methylimidazole, 2-methylimidazole, 2-phenylimidazole, 2-aminoimidazole, and 2-methyl-1-vinylimidazole. , 2-ethyl-4-methylimidazole, 2-heptadecylimidazole, etc., but is not limited thereto.

Specific examples of the boron compounds include tetraphenylphosphonium-tetraphenylborate, triphenylphosphine tetraphenylborate, tetraphenylboron salt, trifluoroborane-n-hexylamine, trifluoroboran monoethylamine, tetrafluoroborane. These include roborantriethylamine and tetrafluoroboranamine.

In addition, the curing accelerators include 1,5-diazabicyclo[4.3.0]non-5-ene (1,5-diazabicyclo[4.3.0]non-5-ene: DBN) and 1,8-diazabicycle. Low[5.4.0]undec-7-ene (1,8-diazabicyclo[5.4.0]undec-7-ene: DBU) and phenol novolac resin salt can be used, but are not limited thereto.

In particular, the use of triphenylphosphine as the curing accelerator is preferable in terms of network formation characteristics because it enables pi-pi stacking with the arylene core structure of the trifunctional or higher epoxy monomer.

The curing accelerator may be included in an amount of 0.01% by weight to 20% by weight, preferably 0.01% by weight to 5% by weight, based on 100% by weight of the trifunctional or higher epoxy monomer (A). When the content of the curing accelerator satisfies the above range, the process time can be shortened by promoting the reaction between the trifunctional or higher epoxy monomer and the curing agent, and the degree of curing of the composition can be improved when sealing a semiconductor device.

Inorganic Filler (D)

The composition for encapsulating a semiconductor device according to an embodiment of the present invention may further include an inorganic filler (D).

The inorganic filler (D) is an ingredient for improving the mechanical properties of the composition for encapsulating semiconductor devices and reducing stress.

As the inorganic filler, general inorganic fillers used for semiconductor encapsulation can be used without limitation.

For example, the inorganic filler includes silica such as alumina, fused silica, crystalline silica, and finely divided silica, silicon nitride, aluminum nitride, aluminum hydroxide, magnesium hydroxide, zinc molybdate, zinc borate, etc., one of these More than one species can be used. Among these, it is more preferable to use alumina from the viewpoint of excellent thermal conductivity.

Additionally, as an inorganic filler, it is also desirable to include a component that can impart flame retardancy, such as aluminum hydroxide, magnesium hydroxide, zinc borate, and zinc molybdate.

The shape of the inorganic filler is not limited, but includes powder form, spherical shape, fibrous form, etc., and spherical inorganic filler is preferred in terms of fluidity and wear resistance.

The average particle diameter (D ₅₀ ) of the inorganic filler may be 0.1 ㎛ to 30 ㎛. In the above average particle size range, fluidity is good and thermal conductivity and relative dielectric constant are excellent.

The inorganic filler may be previously coated with a silane coupling agent, epoxy resin, or curing agent, if necessary.

The inorganic filler may be included in an amount of 99% by weight or less, for example, 10 to 99% by weight, preferably 80 to 99% by weight, based on the total 100% by weight of the composition for sealing semiconductor devices, but has poor formability and low stress. It can be used by adjusting it according to the required properties such as , and high temperature strength.

Additive (F)

In addition to the above components, the composition for encapsulating semiconductor devices according to an embodiment of the present invention may contain additives such as silane coupling agents, release agents, and colorants according to the needs of those skilled in the art, within the range that does not impair the purpose of the present invention.

The silane coupling agent reacts between the epoxy resin and the inorganic filler and serves to improve the interfacial strength of the epoxy resin and the inorganic filler. Specific examples of the silane coupling agent include epoxysilane, aminosilane, mercaptosilane, and ureidosilane, but are not particularly limited thereto. These can be used individually or in combination of two or more types.

The silane coupling agent may be included in an amount of 0.01 to 5% by weight, preferably 0.05 to 3% by weight, and more preferably 0.1 to 2% by weight, based on 100% by weight of the total composition for encapsulating semiconductor devices. When the content of the silane coupling agent satisfies the above range, the strength of the cured product of the epoxy resin composition may be improved.

The release agent serves to facilitate separation from the mold when sealing a semiconductor. The release agent may be one or more selected from the group consisting of paraffin-based wax, ester-based wax, higher fatty acid, higher fatty acid metal salt, natural fatty acid, and natural fatty acid metal salt, but is not particularly limited thereto.

The release agent may be included in an amount of 0.1 to 1% by weight, preferably 0.15 to 0.7% by weight, and more preferably 0.2 to 0.5% by weight, based on 100% by weight of the composition for encapsulating semiconductor devices. When the content of the release agent satisfies the above range, excellent release properties from the mold can be obtained without deteriorating the adhesion between the epoxy resin composition and the semiconductor substrate, thereby preventing molding defects.

The colorant is for laser marking when sealing a semiconductor device, and colorants well known in the art can be used. For example, the colorant may be carbon black, titanium black, titanium nitride, dicopper hydroxide phosphate, iron oxide, mica, etc., but is not particularly limited thereto.

The colorant may be included in an amount of 0.01 to 5% by weight, preferably 0.05 to 3% by weight, and more preferably 0.1 to 2% by weight, based on 100% by weight of the composition for encapsulating semiconductor devices. When the content of the colorant satisfies the above range, laser marking on the semiconductor device encapsulant is easy without impairing the purpose of the present invention.

One embodiment of the present invention relates to a semiconductor device sealed using the composition for sealing a semiconductor device described above.

A semiconductor device sealed using a composition for sealing a semiconductor device can be understood as a semiconductor package and may include a substrate, a semiconductor device, a sealing layer, and a connection terminal.

The substrate supports the semiconductor device and provides electrical signals to the semiconductor device, and semiconductor mounting substrates commonly used in the art may be used without limitation. For example, the substrate may include a circuit board, a lead frame substrate, or a redistribution layer.

The semiconductor device is mounted on the substrate. At this time, the semiconductor device mounting method is not particularly limited, and semiconductor chip mounting techniques known in the art can be used without limitation. For example, the semiconductor device may be mounted on a substrate by a method such as flip chip or wire bonding, and may be made of a single semiconductor chip, or multiple semiconductor chips may be formed with through silicon vias ( It may include a number of semiconductor chips, such as a stacked semiconductor device stacked to enable conduction of electricity through a through silicon via (TSV).

The sealing layer is for protecting the semiconductor device from the external environment and is formed from the composition for sealing a semiconductor device according to the present invention described above. The sealing layer is formed to seal at least a portion of the semiconductor device on the upper part of the substrate.

As a method for sealing electronic component devices such as semiconductor devices using the composition for sealing semiconductor devices of the present invention, methods generally used in the relevant technical field can be used, the low pressure transfer molding method being the most common, injection molding method, Compression molding methods, etc. may also be used, and dispensing methods, mold methods, printing methods, etc. may be used.

The connection terminal for electrically connecting the substrate and an external power source is formed on the lower surface of the substrate, that is, on the surface opposite to the surface on which the semiconductor device is mounted. The connection terminal may be a connection terminal of various structures well known in the art, for example, a lead, a ball grid array, etc., without limitation.

Hereinafter, the present invention will be described in more detail through examples, comparative examples, and experimental examples. These examples, comparative examples, and experimental examples are only for illustrating the present invention, and it is obvious to those skilled in the art that the scope of the present invention is not limited thereto.

Examples 1 to 3 and Comparative Examples 1 to 6: Preparation of composition for encapsulating semiconductor devices

Each component was mixed using a mixer at room temperature according to the composition shown in Table 1 below, melt-kneaded at 90°C, cooled, and pulverized to prepare a composition for sealing semiconductor devices (unit: weight %).

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 epoxy compound A-1 60.1 60.1 9 A-2 59.5 A-3 62.4 9.4 A-4 72.8 57.7 A-5 65.2 hardener B-1 39 39 5.9 39.6 36.7 26.1 33.8 5.5 B-2 41.4 Hardening accelerator C-1 0.9 0.1 0.9 0.9 1.1 0.9 One 0.1 C-2 0.9 inorganic filler D-1 85 85

A-1: Tris(4-hydroxyphenyl)methane triglycidyl ether (epoxy equivalent weight 154 g/eq, Sigma Aldrich)

A-2: Phenyl glycidyl ether (monofunctional epoxy monomer, epoxy equivalent weight 150.2 g/eq, Sigma Aldrich)

A-3: Bisphenol A diglycidyl ether (bifunctional epoxy monomer, epoxy equivalent weight 170.2 g/eq, Sigma Aldrich)

A-4: KSE-3060 (biphenyl type, monofunctional epoxy oligomer, epoxy equivalent weight 278.8 g/eq, Kukdo Chemical)

A-5: YX-4000H (biphenyl type, bifunctional epoxy oligomer, epoxy equivalent weight 193 g/eq, Mitsubishi Chemical)

B-1: KSN-3010 (phenol type hardener, hydroxyl equivalent 100 g/eq, Kukdo Chemical)

B-2: KSN-2010 (phenol type hardener, hydroxyl equivalent weight 200 g/eq, Kukdo Chemical)

C-1: Triphenylphosphine (Sigma Aldrich)

C-2: 2P4MHZ-PW (Shigoku Chemical Industry)

D-1: Spherical alumina particles with a maximum particle diameter of 45㎛

Experimental Example 2:

The glass transition temperature and thermal conductivity of the compositions for encapsulating semiconductor devices prepared in the above examples and comparative examples were measured by the following method, and the results are shown in Table 2 below.

(1) Glass transition temperature

The glass transition temperature was measured by increasing the temperature at 10°C per minute using a differential scanning calorimeter (DSC).

In Table 2 below, 'X' indicates that the glass transition temperature cannot be measured.

(2) Thermal conductivity

Thermal conductivity was measured by curing the composition for encapsulating semiconductor devices in a heated extruder, and finally, after 5 hours of post-curing, a specimen measuring 10 mm wide, 10 mm long, and 1 mm thick was manufactured.

In Table 2 below, 'X' indicates the impossibility of measurement due to the inability to manufacture the cured product.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Glass transition temperature (℃) 203.8 214.6 205.2 X 127.4 150.3 124.4 153.2 128.1 Thermal conductivity (W/m·K) 0.244 0.251 3.454 X 0.227 0.222 0.206 0.228 2.146

As shown in Table 2, the compositions for encapsulating semiconductor devices of Examples 1 and 2 using epoxy monomers having more than three functionality are similar to those of Comparative Examples 1 to 5 using epoxy monomers having less than trifunctionality, or epoxy oligomers. It can be seen that the glass transition temperature of the composition for encapsulating semiconductor devices is higher than that of the composition for encapsulating devices, and the thermal conductivity of the cured product also increases.

Even when it further contains an inorganic filler, the composition for sealing a semiconductor device of Example 3 using an epoxy monomer having more than three functions is superior to the composition for sealing a semiconductor device of Comparative Example 6 using an epoxy monomer having less than three functions. It can be seen that the glass transition temperature is high and the thermal conductivity of the cured product also increases.

As the specific parts of the present invention have been described in detail above, it is clear to those skilled in the art that these specific techniques are merely preferred embodiments and do not limit the scope of the present invention. do. Anyone skilled in the art to which the present invention pertains will be able to make various applications and modifications within the scope of the present invention based on the above contents.

Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

Claims (6)

A composition for sealing semiconductor devices comprising a trifunctional or higher epoxy monomer and a curing agent. The composition for encapsulating a semiconductor device according to claim 1, wherein the trifunctional or higher epoxy monomer includes a compound represented by the following formula (1):
[Formula 1]

In the above equation,
R is an arylene group,
n is an integer from 3 to 8. The composition for encapsulating a semiconductor device according to claim 1, wherein the trifunctional or higher epoxy monomer is at least one selected from compounds represented by the following formulas 1-1 to 1-2:
[Formula 1-1]

[Formula 1-2]
The composition for encapsulating semiconductor devices according to claim 1, wherein the trifunctional or higher epoxy monomer has a molecular weight of 300 to 1,000. The composition for encapsulating a semiconductor device according to claim 1, further comprising at least one selected from the group consisting of an inorganic filler, a curing accelerator, a silane coupling agent, a mold release agent, and a colorant. A semiconductor device sealed using the composition for sealing a semiconductor device according to any one of claims 1 to 5.