WO2016056286A1 - Semiconductor device including heat-conductive silicone grease - Google Patents

Abstract

The present invention provides a highly reliable semiconductor device that includes a heat-conductive silicone grease composition and that constantly exhibits a superior heat dissipation effect even under a high-temperature, high-humidity environment. This semiconductor device has a heat-conductive silicone grease composition between a heat-generating electronic component and a heat-dissipating member and is characterized in that the heat-conductive silicone grease composition is shielded from outside air.

Description

Semiconductor device using thermally conductive silicone grease

The present invention relates to a semiconductor device using a thermally conductive silicone grease composition having excellent thermal conductivity.

Since electronic components such as CPUs, which are electronic components mounted on a printed circuit board, may be degraded in performance or damaged due to temperature rise due to heat generation during use, conventionally, between electronic components and radiating fins, etc. In addition, heat-dissipating sheets and heat-dissipating grease with good thermal conductivity are used. There is an advantage that the heat dissipation sheet can be easily placed. However, even though the surface of the CPU and heat radiating fins may look smooth at first glance, there are irregularities when viewed microscopically. Inconvenience occurs that cannot be performed as per the performance.

In order to solve this problem, an adhesive layer or the like provided on the surface of the heat dissipation sheet to improve the adhesion has been proposed, but it is not sufficient. On the other hand, heat-release grease can follow and adhere to these adherends without being affected by surface irregularities such as CPU and heat-release fins. There were problems such as spills.

For these reasons, methods using a liquid silicone rubber composition as a potting agent or an adhesive have been proposed (Patent Documents 1 and 2). However, since the composition after curing is very hard, it cannot follow the silicon chip warp that occurs during CPU operation and peels off from the base material, etc., resulting in an increase in thermal resistance over time, and the desired heat dissipation performance. There were problems such as being unable to obtain.

In order to solve these problems, materials having flexibility even after curing have been developed (Patent Documents 3 and 4). However, when the heat generation of the CPU is very large, the heat dissipation performance of these is not sufficient. In the case where the heat generation of the CPU is very large, a method of dispersing gallium or a gallium alloy or the like in silicone has been proposed in order to enhance the heat dissipation performance (Patent Documents 5 and 6), but gallium is oxidized under high temperature and high humidity. It was not practical because it was easy to progress and performance deteriorated over time.

JP-A 61-157469 Japanese Patent Application Laid-Open No. 8-208993 Japanese Patent No. 3580366 Japanese Patent No. 3580358 Japanese Patent No. 4551074 JP2013-82816A

An object of the present invention is to provide a highly reliable semiconductor device using a thermally conductive silicone grease composition that overcomes the above-described drawbacks and can continuously obtain a good heat dissipation effect even under high temperature and high humidity. To do.

As a result of intensive studies to solve the above problems, the inventors of the present invention can prevent the heat conductive silicone grease composition from being deteriorated if the heat conductive silicone grease composition is configured to be blocked from the outside air. The present invention has been completed by finding that a highly reliable semiconductor product that continuously exhibits a good heat dissipation effect even under high temperature and high humidity can be obtained.

That is, the present invention provides a semiconductor device using the following thermally conductive silicone grease composition.
[1] A semiconductor device in which a thermally conductive silicone grease composition is disposed between a heat-generating electronic component and a heat radiating member, wherein the thermally conductive silicone grease composition is shielded from outside air. A semiconductor device.
[2] A curable resin composition other than the thermally conductive silicone grease composition is disposed on the outer periphery of the thermally conductive silicone grease composition, and a substrate to which a heat-generating electronic component is connected, and heat dissipation The semiconductor device according to [1], wherein the semiconductor device is disposed between the members.
[3] The semiconductor device according to [1] or [2], wherein the thermally conductive silicone grease composition contains gallium and / or a gallium alloy.
[4] The thermally conductive silicone grease composition comprises:
(A) Organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in one molecule: 100 parts by mass
(B) Organohydrogenpolysiloxane having two or more hydrogen atoms bonded to a silicon atom in one molecule: Hydrogen bonded to a silicon atom in the component for one alkenyl group in the component (A) The amount that the number of atoms is 0.1-5.0,
(C) Gallium having a melting point of 0 to 70 ° C. and / or its alloy: 1,000 to 20,000 parts by mass,
(D) Thermally conductive filler having an average particle size of 0.1 to 100 μm: 0 to 1,000 parts by mass
(E) Platinum-based catalyst: 0.1 to 500 ppm relative to the mass of component (A), and (G) the following general formula (1)

Wherein R ¹ is the same or different monovalent hydrocarbon group, R ² is an alkyl group, an alkenyl group or an acyl group, a is an integer of 5 to 100, and b is 1 to 3 (It is an integer.)
[4] The semiconductor device according to any one of [1] to [3], wherein the semiconductor device contains 0 to 500 parts by mass of polysiloxane represented by the following formula.
[5] Furthermore, (G-2) the following general formula (2):
R ³ _c R ⁴ _d Si (OR ⁵ ) _4-cd (2)
Wherein R ³ is independently an alkyl group having 6 to 15 carbon atoms, R ⁴ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and R ⁵ is independently And an alkyl group having 1 to 6 carbon atoms, c is an integer of 1 to 3, d is an integer of 0 to 2, and the sum of c + d is an integer of 1 to 3.)
The semiconductor device according to [4], wherein the alkoxysilane compound represented by the formula (A) is contained in an amount of 0.1 to 100 parts by mass with respect to 100 parts by mass of the component (A).
[6] The semiconductor device according to any one of [2] to [5], wherein the curable resin composition contains 10 to 90% by volume of a filler.
[7] The semiconductor device according to any one of [2] to [6], wherein the binder of the curable resin composition is silicone.
[8] After placing the thermally conductive silicone grease composition on the exothermic electronic component and applying the curable resin composition before curing on the substrate so as to surround the exothermic electronic component seamlessly, Any one of [2] to [7], comprising a step of covering the heat-generating electronic component and the applied uncured curable resin composition with a heat radiating member and then heating at 80 to 180 ° C. 2. The semiconductor device according to claim 1.

The semiconductor device of the present invention can provide a high reliability because a good heat dissipation effect can be obtained continuously even under high temperature and high humidity.

It is a figure of the semiconductor device which mounted the silicon die on the substrate. It is the figure which looked at the semiconductor device of FIG. 1 from the horizontal direction. It is a figure which shows the state which apply | coated the heat conductive silicone grease composition and the curable resin composition to the semiconductor device of FIG. FIG. 4 is an elevation view of FIG. 3. It is a figure which shows the heat radiating member (surface) used for this invention. It is a figure which shows the heat radiating member (back surface) used for this invention. It is sectional drawing of the heat radiating member of FIG. It is a figure of the semiconductor device which mounted the heat radiating member on the board | substrate. FIG. 9 is an elevation view of FIG. 8. It is the figure which looked at the cross section of FIG. 8 from the horizontal direction. It is a figure before assembling the apparatus used for an Example. It is a figure after assembling the apparatus used for an Example. It is detailed sectional drawing of the semiconductor device of this invention.

Hereinafter, the semiconductor device using the thermally conductive silicone grease composition of the present invention will be described in detail, but the present invention is not limited thereto.

The present invention relates to a semiconductor device in which a thermally conductive silicone grease composition is disposed between a heat-generating electronic component and a heat dissipation member, wherein the thermally conductive silicone grease composition is shielded from the outside air. Features.

As one aspect of the semiconductor device of the present invention, a curable resin composition other than the thermally conductive silicone grease composition is disposed on the outer periphery of the thermally conductive silicone grease composition, and an exothermic electronic component is provided. What is arrange | positioned between the board | substrate with which is connected, and the thermal radiation member is mentioned. Here, since the curable resin composition is arranged so as to surround the heat-generating electronic component without interruption, the thermally conductive silicone grease composition is shielded from the outside air in combination with the substrate and the heat radiating member. To do.

To manufacture the semiconductor device of this embodiment, for example, the thermally conductive silicone grease composition is placed on a heat-generating electronic component, and the curable resin before curing so as to surround the heat-generating electronic component seamlessly. An example is a method in which after the composition is applied on a substrate, a heat radiating member is placed on the exothermic electronic component and the applied curable resin composition before curing, and then heated at 80 to 180 ° C.

Details of this method will be described with reference to the drawings.
FIGS. 1 to 10 are diagrams for explaining necessary parts or manufacturing steps for explaining the present invention in detail, and are simplified, and a specific semiconductor device of the present invention is shown in FIG. 13 will be described later.

FIG. 1 is a plan view of a semiconductor device in which a silicon die 11 is mounted on a substrate 12. FIG. 2 is an elevation view of the semiconductor device of FIG.
FIG. 3 shows a curable resin composition different from the thermally conductive silicone grease composition 13 in which a thermally conductive silicone grease composition 13 is applied onto the silicon die 11 and the silicon die 11 is surrounded without any breaks. It is a figure of the state which apply | coated the thing. The thermal conductive silicone grease 13 and the curable resin composition 14 are applied by applying silicone resin in a container such as a syringe and extruding the silicone resin from the needle tip of the syringe using air pressure or nitrogen pressure. Application is preferred. By using dispense application, the amount of silicone resin applied can be precisely controlled. The thermally conductive silicone grease composition 13 and the curable resin composition 14 are preferably applied by dispensing application, but the application method is not particularly limited.

FIG. 4 is an elevation view of FIG. The height after application of the curable resin composition 14 must be at least higher than the silicon die 11 at all points. This is because in the next step, when the heat-dissipating member such as a heat spreader is covered, if the height of the cured resin composition 14 is not higher than that of the silicon die 11, the curable resin composition 14 is physically This is because it is difficult to block the outside air because it does not contact both the substrate 12 and the heat dissipation member.
5 and 6 show the heat spreader 15 of the heat radiating member used in the present invention. 5 and 6 show the same heat spreader 15. FIG. 6 is a reverse view of FIG. Although the X plane in FIG. 5 is flat, the Y plane in FIG. 6 is a plane that is one step lower than the edge portion 16. The Y surface side is a surface in contact with the heat conductive silicone grease composition 13 and the curable resin composition 14. FIG. 7 is a cross-sectional view of FIG. The height of the edge portion 16 is preferably equal to or slightly higher than the height of the silicon die 11 from the substrate 12.

The material of the sheet spreader 15 of the heat radiating member is preferably copper, and more preferably the surface is coated with nickel. As shown in FIGS. 8 and 9, the heat spreader 15 as the heat radiating member is covered with the heat conductive silicone grease composition 13 and the curable resin composition 14 so as to cover the whole, and is pressed from above, and then 80 to 180 ° C. Heat with. By this heating, the heat conductive silicone composition 13 and the curable resin composition 14 are cured. In addition, in order to adhere the heat spreader 15 which is a heat radiating member to the board | substrate 12, it is preferable to use the adhesive material 17 as shown in FIG. 9 is a view of FIG. 8 viewed from the side, and FIG. 10 is a view of the cross-sectional view of FIG. 8 viewed from the side.
Further, front and rear perspective views of the heat spreader are shown in FIGS. 11 and 12, respectively.

A cross-sectional view of the finished product is shown in FIG. Since the curable resin composition 14 physically suppresses or reduces the entry of water vapor, oxidation of gallium or a gallium alloy contained in the heat conductive silicone grease composition 13 can be suppressed.

Next, the thermally conductive silicone grease composition that is preferably used in the present invention will be described. The thermally conductive silicone grease composition used in the present invention preferably contains (A) component, (B) component, (C) component, (D) component, (E) component and (G) component.
Hereinafter, each component will be described in detail.

<(A) Organopolysiloxane>
The component (A) of the composition used in the present invention is an organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in one molecule, and is a main agent (base polymer) in an addition reaction curing system. If this organopolysiloxane is liquid, its molecular structure is not limited. For example, it may be linear, branched, partially branched, etc. is there.

Examples of the alkenyl group include a vinyl group, an allyl group, a 1-butenyl group, and a 1-hexenyl group. Among these, a vinyl group having high versatility is preferable. This alkenyl group may be bonded to either a silicon atom at the end of the molecular chain or a silicon atom in the middle of the molecular chain, but in order to make the resulting cured product flexible, It is preferable that it is bonded only to.

(A) As a group couple | bonded with silicon atoms other than the alkenyl group in a component, it is an unsubstituted or substituted monovalent hydrocarbon group, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, hexyl Group, heptyl group, octyl group, nonyl group, decyl group, dodecyl group and other alkyl groups; cyclopentyl group, cyclohexyl group and other cycloalkyl groups; phenyl group, tolyl group, xylyl group, naphthyl group and other aryl groups; benzyl group Aralkyl groups such as 2-phenylethyl group and 2-phenylpropyl group; halogenated alkyl groups such as chloromethyl group, 3,3,3-trifluoropropyl group and 3-chloropropyl group. In particular, 90% or more of these groups are preferably methyl groups from the viewpoint of synthesis and economy.

The viscosity of this organopolysiloxane at 25 ° C. is preferably in the range of 0.05 to 100 Pa · s, particularly preferably in the range of 0.1 to 50 Pa · s. If the viscosity is too low, the storage stability of the resulting composition will be poor, and if it is too high, the extensibility of the resulting composition may be poor. This viscosity can be measured using a spiral viscometer PC-ITL (manufactured by Malcolm).

Preferable specific examples of such organopolysiloxanes include dimethylvinylsiloxy group-capped polydimethylsiloxane having molecular chains at both ends, methyldivinylsiloxy group-capped polydimethylsiloxane having molecular chains at both ends, and dimethylvinylsiloxy-capped dimethylsiloxane having molecular chains at both ends. -A methylphenylsiloxane copolymer etc. are mentioned.

The organopolysiloxane of component (A) can be used alone or in combination of two or more having different viscosities.

<(B) Organohydrogenpolysiloxane>
Component (B) of the composition used in the present invention is an organohydrogenpolysiloxane having two or more hydrogen atoms bonded to silicon atoms (hereinafter referred to as “SiH groups”) in one molecule. A) It acts as a crosslinking agent for the component. That is, the SiH group in the component (B) is added by the hydrosilylation reaction with the alkenyl group in the component (A) by the action of the platinum catalyst of the component (E) described later, and has a three-dimensional network structure having a crosslink. A crosslinked cured product having a structure is provided.

(A) As a group couple | bonded with silicon atoms other than a hydrogen atom in a component, it is an unsubstituted or substituted monovalent hydrocarbon group other than an alkenyl group, for example, The group similar to what was illustrated about (A) component Is mentioned. Among these, a methyl group is preferable from the viewpoint of synthesis and economy. Further, the structure of the organohydrogenpolysiloxane may be linear, branched, cyclic, or a combination thereof.

Preferred specific examples of the organohydrogenpolysiloxane of component (B) include molecular chain both ends trimethylsiloxy group-capped methylhydrogen polysiloxane, molecular chain both ends trimethylsiloxy group-capped dimethylsiloxane / methylhydrogensiloxane copolymer. , Dimethylsiloxane / methylhydrogensiloxane / methylphenylsiloxane copolymer blocked with trimethylsiloxy group blocked at both ends of molecular chain, dimethylpolysiloxane blocked with dimethylhydrogensiloxy group blocked at both ends of molecular chain, dimethylpolysiloxane blocked with dimethylhydrogensiloxy group blocked at both ends of molecular chain Siloxane / methylhydrogensiloxane copolymer, dimethylhydrogensiloxy group-blocked dimethylsiloxane / methylphenylsiloxane copolymer, both ends of the molecular chain Le hydro diene siloxy group-blocked methyl phenylalanine polysiloxane and the like. Moreover, the organohydrogenpolysiloxane of the component (B) can be used singly or in combination of two or more.

The blending amount of the component (B) is such that the number of hydrogen atoms bonded to silicon atoms in the component is 0.1 to 5.0 with respect to one alkenyl group in the component (A). The amount is preferably 0.5 to 3.0. If the number is less than 0.1, a sufficient network structure is not formed, so that the required hardness after curing cannot be obtained, and it is difficult to fix and hold the component (C) described later. Become. On the other hand, when the number exceeds 5.0, the change over time in the physical properties of the obtained cured product increases, and the storage stability may deteriorate.

<(C) Gallium and / or its alloy>
The component (C) of the composition used in the present invention is gallium and / or an alloy thereof having a melting point of 0 to 70 ° C. The component (C) is a component that is blended in order to impart good thermal conductivity to the cured product obtained from the composition used in the present invention, and the use of the composition blended with this component is used in the present invention. This is a characteristic of a semiconductor device.

The melting point of the component (C) needs to be in the range of 0 to 70 ° C. as described above. This is because, after preparing the composition used in the present invention, the dispersion state of each component contained in the composition is maintained, so that it is about −30 to −10 ° C., preferably about −25 during long-term storage and transportation. Although it is necessary to maintain a low temperature state of -15 ° C., when the melting point is less than 0 ° C., liquid fine particles tend to aggregate during long-term storage and transportation as described above. It is relatively difficult to maintain this state. On the other hand, when the temperature exceeds 70 ° C., the composition is not rapidly melted in the preparation process, resulting in poor workability. Therefore, as described above, the range of 0 to 70 ° C. is an appropriate range as well as a necessary condition for handling. In particular, those having a melting point in the range of 15 to 50 ° C. are more preferable because preparation of the composition used in the present invention is easy and handling during the long-term storage and transportation is simple. In addition, it is easy to form a heat conductive path by agglomeration and connection of the liquid fine particles of the component (C) under the heat treatment conditions for curing the composition. The inside is more preferable.

Incidentally, the melting point of metallic gallium is 29.8 ° C. Typical gallium alloys include, for example, gallium-indium alloys; for example, Ga-In (mass ratio = 75.4: 24.6, melting point = 15.7 ° C.), gallium-tin alloys, gallium-tin- Zinc alloy; for example, Ga—Sn—Zn (mass ratio = 82: 12: 6, melting point = 17 ° C.), gallium-indium-tin alloy; for example, Ga—In—Sn (mass ratio = 21.5: 16.0: 62.5, melting point = 10.7 ° C.), gallium-indium-bismuth-tin alloy; for example, Ga—In—Bi—Sn (mass ratio = 9.4: 47.3: 24.7: 18.6, melting point) = 48.0 ° C.) and the like.

This component (C) can be used alone or in combination of two or more.

The shape of the liquid fine particles or solid fine particles of gallium and / or an alloy thereof present in the composition used in the present invention in an uncured state is usually substantially spherical, but may include irregular shapes. . In addition, the average particle diameter is usually 0.1 to 100 μm, preferably 5 to 50 μm. If the average particle size is too small, the viscosity of the composition will be too high, and the extensibility will be poor, so there will be a problem in coating workability, and conversely if it is too large, the composition will be non-uniform. It may be difficult to apply a thin film to exothermic electronic components. In addition, since the shape and average particle diameter, as well as the dispersion state in the composition, are stored at a low temperature immediately after the preparation of the composition as described above, until the coating process to the heat-generating electronic components, etc. Can be maintained. The average particle diameter is a volume-based cumulative average diameter, which is measured by a laser scattering method [Microtrack MT3300EX (manufactured by Nikkiso Co., Ltd.)].

The amount of component (C) is 1,000 to 20,000 parts by weight, preferably 3,000 to 17,000 parts by weight, particularly preferably 100 parts by weight of component (A). Is from 5,000 to 1,5000. When the blending amount is less than 1,000 parts by mass, the thermal conductivity is lowered, and when the composition is thick, sufficient heat dissipation performance cannot be obtained. When the amount is more than 20,000 parts by mass, it is difficult to obtain a uniform composition, and the viscosity of the composition becomes too high, so that the composition cannot be obtained as an extensible grease. There is.

<(D) Thermally conductive filler>
In the composition of the present invention, together with the component (C), a heat conductive filler to be blended in a conventionally known heat conductive sheet or heat conductive grease can be blended. If the amount is more than 1,000 parts by mass, the viscosity of the composition becomes high, and there is a problem that the composition cannot be obtained as a grease-like material having extensibility. The range is 000 parts by mass, and preferably 50 to 500 parts by mass.

The component (D) is not particularly limited as long as it has a good thermal conductivity, and any conventionally known one can be used. For example, aluminum powder, zinc oxide powder, alumina powder, boron nitride Examples thereof include powder, aluminum nitride powder, silicon nitride powder, copper powder, diamond powder, nickel powder, zinc powder, stainless steel powder, and carbon powder. Further, the component (D) can be used alone or in combination of two or more.

However, if a material having high reactivity with gallium such as aluminum is used, it may aggregate during mixing and kneading when preparing the composition, and uniform mixing may be difficult. In this case, first, the uniform dispersion of the liquid fine particles of the component (C) in the mixed liquid component of the components (A) and (G) is completed, and the component (C) is converted into the components (A) and (G). After being in a state of being coated with the component mixture, the component (D) may be added and blended and kneaded. By doing so, aggregation of the component (D) can be prevented.

(D) The average particle diameter of the component (D) is in the range of 0.1 to 100 μm, preferably in the range of 1 to 20 μm. If the average particle size is too small, the resulting composition will have too high a viscosity, resulting in poor extensibility. On the other hand, if it is too large, it is difficult to obtain a uniform composition. This average particle diameter is a volume-based cumulative average diameter and is measured by a laser scattering method [Microtrack MT3300EX (manufactured by Nikkiso Co., Ltd.)].

<(E) Platinum-based catalyst>
The platinum-based catalyst of the component (E) of the composition used in the present invention promotes the addition reaction between the alkenyl group in the component (A) and SiH in the component (B), and the composition used in the present invention. It is a component blended to give a cross-linked cured product in a three-dimensional network state.

As the component (E), all known compounds used in ordinary hydrosilylation reactions can be used. For example, platinum metal (platinum black), chloroplatinic acid, platinum-olefin complex, platinum-alcohol complex, Examples include platinum coordination compounds. (E) The compounding quantity of a component should just be an effective amount required in order to harden the composition used for this invention, Although it does not specifically limit, For example, normally with respect to the mass of (A) component as a platinum atom. 0.1 to 500 ppm is preferable.

<(F) Addition reaction control agent>
The addition reaction control agent for the component (F) of the composition used in the present invention is a component that is blended as necessary, and the hydrosilylation reaction is suppressed by the action of the platinum-based catalyst at room temperature, and the composition used in the present invention. It is a component that is blended so as to ensure the pot life (shelf life, pot life) and to prevent the coating work on the heat-generating electronic parts and the like.

As the component (F), all known addition reaction control agents used in ordinary addition reaction curable silicone compositions can be used. For example, 1-ethynyl-1-cyclohexanol, 3-butyne-1 -Acetylene compounds such as ol, various nitrogen compounds, organic phosphorus compounds, oxime compounds, organic chloro compounds and the like.

The blending amount of the component (F) varies depending on the amount of the component (E) used and cannot be generally specified, but is not particularly limited as long as it is an effective amount capable of suppressing the progress of the hydrosilylation reaction. For example, it is usually preferably about 0.001 to 5 parts by mass with respect to 100 parts by mass of component (A). If the amount of component (F) is too small, sufficient pot life may not be ensured, and if too large, the curability of the composition used in the present invention may decrease. In addition, in order to improve the dispersibility in a composition, this (F) component can also be used by diluting with organic solvents, such as toluene, xylene, and isopropyl alcohol, as needed.

<(G) Surface treatment agent>
The composition used in the present invention comprises hydrophobizing the component (C) gallium and / or its alloy during preparation of the composition, and the component (A) liquid particle organopolysiloxane (C) And (G) a polysiloxane represented by the following general formula (1) for the purpose of uniformly dispersing the component (C) as fine particles in a matrix composed of the component (A). It is preferable to mix as a surface treatment agent.

In addition, the component (G) also has the function of improving the wettability of the surface of the thermally conductive filler of the component (D) and improving the uniform dispersibility.
As the component (G), the following general formula (1):

Wherein R ¹ is the same or different monovalent hydrocarbon group, R ² is an alkyl group, an alkenyl group or an acyl group, a is an integer of 5 to 100, and b is 1 to 3 (It is an integer.)
And a polysiloxane having one end of a molecular chain blocked with a hydrolyzable group, and a kinematic viscosity at 25 ° C. of 10 to 10,000 mm ² / s.
The kinematic viscosity is a value measured with an Ostwald viscometer.

When the blending amount of the (G) component is more than 500 parts by mass with respect to 100 parts by mass of the (A) component, there is a problem that the finished composition is difficult to cure because the (A) component is relatively decreased. If the composition used in the present invention is not cured, after the grease is applied to the IC package, the adhesion may be shifted and the performance may be significantly lowered. Accordingly, the blending amount of the component (G) is in the range of 0 to 500 parts by mass, preferably 50 to 200 parts by mass.

Further, in some cases, the following alkoxysilane may be blended as part of the component (G).
(G-2) The following general formula (2):
R ³ _c R ⁴ _d Si (OR ⁵ ) _4-cd (2)
Wherein R ³ is independently an alkyl group having 6 to 15 carbon atoms, R ⁴ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and R ⁵ is independently And an alkyl group having 1 to 6 carbon atoms, c is an integer of 1 to 3, d is an integer of 0 to 2, and the sum of c + d is an integer of 1 to 3.)

Examples of R ³ in the general formula (2) include a hexyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group, and a tetradecyl group. When the number of carbon atoms is less than 6, the wettability of the component (C) and the component (D) is not sufficiently improved, and when it exceeds 15, the organosilane of the component (G-2) is solidified at room temperature. In addition to being inconvenient to handle, the low temperature properties of the resulting composition are reduced.

The general formula (2) R ⁴ includes, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group, a hexyl group and an octyl group; a cycloalkyl group such as a cyclopentyl group and a cyclohexyl group; a vinyl group and an allyl group Alkenyl groups such as phenyl group, tolyl group and the like; aralkyl groups such as 2-phenylethyl group and 2-methyl-2-phenylethyl group; 3,3,3-trifluoropropyl group, 2- (nano And halogenated hydrocarbon groups such as a fluorobutyl) ethyl group, a 2- (heptadecafluorooctyl) ethyl group, and a p-chlorophenyl group. Among these, a methyl group and an ethyl group are particularly preferable.

Further, the above-mentioned R ^5, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, an alkyl group such as hexyl group. Among these, a methyl group and an ethyl group are particularly preferable.

Preferable specific examples of the component (G-2) include the following.
C ₆ H ₁₃ Si (OCH ₃ ) ₃
C ₁₀ H ₂₁ Si (OCH ₃ ) ₃
C ₁₂ H ₂₅ Si (OCH ₃ ) ₃
C ₁₂ H ₂₅ Si (OC ₂ H ₅ ) ₃
C ₁₀ H ₂₁ Si (CH ₃ ) (OCH ₃ ) _{2
C 10 H 21 Si (C 6} H 5) (OCH 3) 2
_{C 10 H 21 Si (CH 3} ) (OC 2 H 5) 2
C ₁₀ H ₂₁ Si (CH═CH ₂ ) (OCH ₃ ) _{2
C 10 H 21 Si (CH 2} CH 2 CF 3) (OCH 3) 2

This component (G-2) can be used alone or in combination of two or more. The blending amount is 0.1 to 100 parts by mass, more preferably 1 to 50 parts by mass with respect to 100 parts by mass of the component (A). When the blending amount is too large, the wetter effect does not increase and it is uneconomical. Since it is somewhat volatile, the composition used in the present invention gradually becomes harder if left in an open system. There is.

<Viscosity of thermally conductive silicone grease composition>
As will be described later, the composition used in the present invention is applied to the surface of the heat-generating electronic component, and after heat-contacting the heat-dissipating member, the composition is cured by heat treatment to form a heat conductive layer. At this time, in order to improve workability, the composition used in the present invention needs to be in the form of grease.

For example, the composition used in the present invention is accommodated in a syringe, applied from the syringe onto the surface of a heat-generating electronic component such as a CPU, and a coating layer is formed, and a heat radiating member is pressed against this. Accordingly, the absolute viscosity at 25 ° C. of the composition used in the present invention is preferably 10 to 1,000 Pa · s, and particularly preferably 50 to 400 Pa · s. If the absolute viscosity is too low, dripping may occur during the application, which may cause a problem in operation. On the other hand, if the absolute viscosity is too high, extrusion from the syringe becomes difficult, and the efficiency of the coating operation may be deteriorated. This viscosity can be measured with a spiral viscometer PC-ITL (Malcom Co., Ltd.).

<Preparation of thermally conductive silicone grease composition used in the present invention>
The thermally conductive silicone grease composition used in the present invention is:
(I) When the component (A), the component (C), the component (D), the component (G) and the component (G-2) are included, the temperature of the component is in the range of 40 to 120 ° C. And kneading at a temperature equal to or higher than the melting point of the component (C) to obtain a uniform mixture;
(Ii) stopping kneading and cooling the temperature to below the melting point of component (C); and (iii) component (B), component (E), component (F), and A step of adding the other components by kneading at a temperature lower than the melting point of the component (C) to obtain a uniform mixture;
It can obtain by the manufacturing method containing.

In the production method, a stirring / kneading machine such as a conditioning mixer or a planetary mixer provided with a heating means and, if necessary, a cooling means can be used.

In the step (i), the liquid material of gallium and / or its alloy as the component (C) and the thermally conductive filler as the component (D) are the components (A) and (G), or (A) It is uniformly dispersed in a mixed solution of the component, the component (G) and the component (G-2).

It is preferable that the temperature lowering operation or the cooling operation in the step (ii) is performed promptly. In the step (ii), liquid fine particles uniformly dispersed in a matrix composed of the component (A) and the component (G) or the mixed solution of the component (A), the component (G) and the component (G-2) The component (C) in the state solidifies while maintaining its average particle diameter and the dispersed state.

It is preferable that the step (iii) is also completed in as short a time as possible. At the end of the step (iii), there is substantially no change in the dispersion state of the solidified fine particles of the component (C). After the completion of the step (iii), the produced composition is accommodated in a container, and quickly, a freezer having a temperature of about −30 to −10 ° C., preferably about −25 to −15 ° C., a freezer, etc. It is preferable to store in Further, it is preferable to use a vehicle or the like equipped with a refrigeration facility for its transportation. By storing and transporting at a low temperature as described above, the composition and dispersion state of the composition used in the present invention can be stably maintained even after long-term storage, for example.

Next, the curable resin composition other than the heat conductive silicone grease composition used in the present invention will be described in detail. The binder resin used in the curable resin composition used in the present invention is not particularly limited to silicone, but silicone is preferable from the viewpoint of heat resistance and stress relaxation. When the curable resin composition is cured by a hydrosilylation reaction, it is composed of the same component (A), component (B), component (E) and filler as the thermally conductive silicone resin composition. The component (G) and / or the component (F) may be contained, but the component (C) must not be contained. The blending ratio of the component (B) and the component (E) to the component (A) used for the curable resin is the same as that of the thermally conductive silicone grease composition. Even when the component (G) and / or the component (F) is contained, the ratio to the component (A) is the same as that of the thermally conductive silicone grease composition.

The above curable resin composition preferably contains 5 to 90% by volume of filler in the composition. If the filler is less than 5% by volume, water vapor entering from the surroundings may not be sufficiently prevented, and if it exceeds 90% by volume, the fluidity of the curable resin composition is lost. The content of the filler is preferably 10 to 80% by volume, more preferably 15 to 70% by volume.

The filler used in the curable resin composition may be the same as the component (D) used in the above-described thermally conductive silicone resin composition, or may be surface-treated fumed silica.

Here, as the surface treatment agent for the surface-treated fumed silica, for example, chlorosilane, silazane, and siloxane are effective. Specific examples of the surface treatment agent include methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, hexamethyldisilazane, octamethylcyclotetrasiloxane, α, ω-trimethylsilyldimethylpolysiloxane, and the like.

Further, the specific surface area (BET method) of the surface-treated fumed silica is preferably 50 m ² / g or more, more preferably 100 to 500 m ² / g. When the specific surface area is less than 50 m ² / g, the viscosity of the composition may increase.

The method for producing the curable resin composition used in the present invention may be any conventional method for producing a silicone grease composition, and is not particularly limited. For example, the above (A), (B), (E) and filler, and other components as necessary, Trimix, Twinwin, Planetary Mixer (all are mixers manufactured by Inoue Mfg. Co., Ltd., registered) (Trademark), Ultramixer (mixer manufactured by Mizuho Industry Co., Ltd., registered trademark), Hibis Dispermix (mixer manufactured by Tokushu Kika Kogyo Co., Ltd., registered trademark), etc., and mixing for 30 minutes to 4 hours Can be manufactured. If necessary, mixing may be performed while heating at a temperature in the range of 50 to 150 ° C.

With respect to the curable resin composition used in the present invention, the absolute viscosity measured at 25 ° C. is preferably 10 to 600 Pa · s, particularly preferably 10 to 500 Pa · s, and further preferably 20 to 400 Pa. S, and more preferably 30 to 350 Pa · s. The workability is excellent when the absolute viscosity is 10 to 600 Pa · s. The absolute viscosity can be obtained by adjusting each component with the above-described blending amount. The absolute viscosity is measured using a model number PC-1TL (10 rpm) manufactured by Malcolm Corporation.

Hereinafter, although an example and a comparative example are shown and the present invention is explained concretely, the present invention is not limited to the following example. The raw materials used are as follows. Moreover, each measurement was performed as follows.

<Measurement of viscosity>
The absolute viscosity of the composition was measured with a model number PC-1TL (10 rpm) manufactured by Malcolm Corporation.

<Measurement of thermal conductivity>
The thermal conductivity was measured at 25 ° C. using TPA-501 manufactured by Kyoto Electronics Industry Co., Ltd.

<Measurement of particle size>
The particle diameter measurement value of the thermally conductive filler is a volume-based cumulative average diameter measured by Microtrac MT3300EX, a particle size analyzer manufactured by Nikkiso Co., Ltd.

The components (A) to (G) of the thermally conductive silicone grease composition used in the following examples are shown below.

(A) component:
The viscosity at 25 ° C. of dimethylpolysiloxane blocked at both ends with dimethylvinylsilyl groups is as follows: (A-1) Absolute viscosity: 0.6 Pa · s
(A-2) Absolute viscosity: 10.0 Pa · s
(A-3) Absolute viscosity: 30.0 Pa · s

(B) component:
(B-1) The following structural formula:

Organohydrogenpolysiloxane represented by

(C) component:
(C-1) Metallic gallium [melting point = 29.8 ° C.]
(C-2) Ga—In alloy [mass ratio = 75.4: 24.6, melting point = 15.7 ° C.]

(D) component:
(D-1): Alumina powder [average particle size: 8.2 μm]
(D-2): Zinc oxide powder [average particle size: 1.0 μm]

(E) component:
(E-1): dimethylpolysiloxane of platinum-divinyltetramethyldisiloxane complex (both ends blocked with dimethylvinylsilyl groups, viscosity: 0.6 Pa · s) solution [platinum atom content: 1% by mass ]

(F) component:
(F-1) 50% by mass toluene solution of 1-ethynyl-1-cyclohexanol

(G) component:
(G-1) The following structural formula:

One end trimethoxysilyl group-blocked dimethylpolysiloxane having a kinematic viscosity of 32 mm ² / s represented by

(G-2) The following structural formula:
C ₁₂ H ₂₅ Si (OC ₂ H ₅ ) ₃
Organosilane represented by

<Preparation of thermally conductive silicone grease composition>
A composition was prepared by the following method using each component having the composition and amount shown in Table 1.
Add component (A), component (C), component (D) and component (G) to a conditioning mixer (made by Shinky Co., Ltd., trade name: Nertaro Awatori) with an internal volume of 250 ml, and raise the temperature to 70 ° C. The temperature was maintained and kneaded for 5 minutes. The kneading was then stopped and cooled to 15 ° C. Next, component (B), component (E) and component (F) were added, and the above-mentioned temperatures were maintained, and kneaded uniformly to prepare thermally conductive silicone grease compositions -1 to 5.

*: SiH / Vi = number of SiH groups in component (B) relative to one vinyl group in component (A) (hereinafter the same)

The curable resin composition used in the present invention was prepared as follows.

<Curable resin composition-1>
To 100 g of dimethylpolysiloxane having both ends blocked with dimethylvinylsilyl groups, as described in (A-1) above, 800 g of alumina powder (D-1), 200 g of zinc oxide powder (D-2), 20 g of (G-1) one-end-terminated trimethoxysilyl group-blocked dimethylpolysiloxane was charged into a 5 L planetary mixer (both manufactured by Inoue Mfg. Co., Ltd., registered trademark) and stirred at 150 ° C. for 1 hour. It was. Thereafter, after cooling to room temperature, 0.45 g and 0.15 g of (F-1) and (E-1) were added, respectively, and further stirred for 15 minutes. Thereafter, 8.2 g of the organohydrogenpolysiloxane (B-1) was added and stirred for 15 minutes to obtain a curable resin composition-1. At this time, SiH / Vi = 1.0, and the viscosity of the curable resin composition was 250 Pa · s. The amount of the filler in the curable resin composition was 65% by volume.

<Curable resin composition-2>
In the curable resin composition-1, (D-1) alumina powder, (D-2) zinc oxide powder, and (B-1) organohydrogenpolysiloxane were 400 g, 100 g, and 9. A curable resin composition-2 was obtained in the same manner except that the amount was 8 g. At this time, SiH / Vi = 1.2, and the viscosity of the curable resin composition was 105 Pa · s. The amount of the filler in this curable resin composition was 46% by volume.

<Curable resin composition-3>
In the curable resin composition-1, the alumina powder of (D-1) and the zinc oxide powder of (D-2) were changed to the following surface-treated fumed silica, and the addition amount was changed to 50 g. Were all the same to obtain a curable resin composition-3. At this time, SiH / Vi = 1.0, and the viscosity of the curable resin composition was 350 Pa · s. The amount of the filler in this curable resin composition was 15% by volume.

The surface-treated fumed silica is a dry fumed silica having a BET specific surface area of 120 m ² / g and hydrophobized with dimethyldichlorosilane.

<Example 1>
As shown in FIG. 11, 0.3 g of the heat conductive silicone grease composition-1 as the heat conductive silicone grease composition 21 was applied to the center of the slide glass 24 having a length of 50 mm, a width of 70 mm, and a thickness of 1 mm. Then, the curable resin composition-1 as the curable resin composition 22 was applied so that there was no break in the periphery. Thereafter, as shown in FIG. 12, a spacer 23 having a thickness of 0.5 mm is placed on both ends of the slide glass 24, and another slide glass 24 is pressed from the upper side so that the heat conductive silicone grease composition 21 and the curable resin are cured. The resin composition 22 was completely brought into close contact between the upper and lower slide glasses 24 so as to block the heat conductive silicone grease composition 21 from the outside air. Then, it was left in an oven at 150 ° C. for 1 hour to cure the heat conductive silicone grease composition-1 and the curable resin composition-1. Thereafter, the thermally conductive silicone grease composition-1 and the curable resin composition-1 were aged for 1,000 hours under the conditions of 85 ° C./85% RH. After aging, the oxygen content of the thermally conductive silicone grease composition-1 was measured with an oxygen / nitrogen analyzer EMGA-2800 manufactured by Horiba, Ltd. As a result, the oxygen content of the thermally conductive silicone grease composition-1 was 2% by mass.

<Example 2>
The procedure of Example 1 was repeated except that the thermally conductive silicone grease composition 21 of Example 1 was changed to the thermally conductive silicone grease composition-2. As a result, the oxygen content of the thermally conductive silicone grease composition-2 was 3% by mass.

<Example 3>
The procedure of Example 1 was repeated except that the heat conductive silicone grease composition 21 of Example 1 was changed to the heat conductive silicone grease composition-3. As a result, the oxygen content of the thermally conductive silicone grease composition-3 was 2% by mass.

<Example 4>
The procedure of Example 1 was repeated except that the thermally conductive silicone grease composition 21 of Example 1 was changed to the thermally conductive silicone grease composition-4. As a result, the oxygen content of the thermally conductive silicone grease composition-4 was 4% by mass.

<Example 5>
The same procedure as in Example 1 was conducted except that the curable resin composition 22 of Example 1 was changed to the curable resin composition-2. As a result, the oxygen content of the thermally conductive silicone grease composition-1 was 3% by mass.

<Example 6>
The same procedure as in Example 1 was conducted except that the curable resin composition 22 of Example 1 was changed to the curable resin composition-3. As a result, the oxygen content of the thermally conductive silicone grease composition-1 was 3% by mass.

<Example 7>
Example 1 except that the thermally conductive silicone grease composition 21 of Example 1 was changed to the thermally conductive silicone grease composition-2 and the curable resin composition 22 was changed to the curable resin composition-2. As well as. As a result, the oxygen content of the thermally conductive silicone grease composition-2 was 2% by mass.

<Example 8>
Example 1 except that the thermally conductive silicone grease composition 21 of Example 1 was changed to a thermally conductive silicone grease composition-5 and the curable resin composition 22 was changed to a curable resin composition-3. As well as. As a result, the oxygen content of the thermally conductive silicone grease composition-2 was 2% by mass.

<Comparative Example 1>
All operations were performed in the same manner as in Example 1 except that the curable resin composition-1 of Example 1 was not applied. As a result, the oxygen content of the thermally conductive silicone grease composition-1 was 20% by mass.

<Example 9>
[Application to semiconductor devices]
FIG. 13 is a diagram illustrating in detail a semiconductor device of the present invention having a silicon die 31 of 15 mm × 15 mm and a substrate 32. On the silicon die 31, 0.3 g of the heat conductive silicone grease composition-1 that is the heat conductive silicone grease composition 33 obtained in this example is applied, and the silicon die 31 is surrounded without any breaks. Similarly, the curable resin composition-1 which is the curable resin composition 34 obtained in this example was applied so that the width was 1 mm and the coating height was higher than that of the silicon die 31. Further, an adhesive 37 was applied to a portion where the edge portion 36 of the heat spreader 35 as a heat radiating member and the substrate 32 are in contact with each other. From above, the heat spreader 35 is pressed at 50 psi for 1 minute, and then the semiconductor device is left in an oven at 150 ° C. for 1 hour to heat-conductive silicone grease composition 33, curable resin composition 34, and adhesive 37. Cured. At this time, the curable resin composition 34 is in contact with the substrate 32 and the heat spreader 35 without any gaps at all positions around the silicon die 31, thereby blocking the thermally conductive silicone grease composition 33 from the outside air. I am doing so. The silicon die 31 is attached to the substrate 32 via an underfill 38 and solder 39. When the semiconductor device thus obtained was operated at 85 ° C./85% RH for 1,000 hours, the semiconductor device of the present invention was a semiconductor with overheat accumulation as compared to the case without the curable resin composition-1. We were able to prevent the performance degradation and damage of the equipment. Therefore, it was confirmed that the reliability of the semiconductor device was improved by employing the present invention.
After the test of Example 9, the thermally conductive silicone grease composition-1 was taken out and the oxygen content was measured. As a result, the amount of oxygen was 2% by mass.

<Comparative example 2>
When the semiconductor was operated in the same manner as in Example 9 except that the curable resin composition-1 of Example 9 was not used, it did not operate in 750 hours. At this time, the thermally conductive silicone grease composition-1 was taken out and the amount of oxygen was measured. As a result, the oxygen content was 21% by mass.

11: Silicon die 12: Substrate 13: Thermally conductive silicone grease composition 14: Curable resin composition 15: Heat radiating member (heat spreader)
16: Edge portion of heat spreader 17: Adhesive 21: Thermally conductive silicone grease composition 22: Curable resin composition 23: 0.5 mm spacer 24: Slide glass 31: Silicon die 32: Substrate 33: Thermal conductivity Silicone grease composition 34: Curable resin composition 35: Heat radiating member (heat spreader)
36: Edge portion of heat spreader 37: Adhesive 38: Underfill 39: Solder

Claims (8)

1. A semiconductor device in which a thermally conductive silicone grease composition is disposed between an exothermic electronic component and a heat dissipation member, wherein the thermally conductive silicone grease composition is shielded from outside air apparatus.
2. A curable resin composition other than the thermally conductive silicone grease composition is disposed on the outer periphery of the thermally conductive silicone grease composition, and a substrate to which a heat generating electronic component is connected, and a heat radiating member The semiconductor device according to claim 1, wherein the semiconductor device is disposed between the semiconductor devices.
3. The semiconductor device according to claim 1 or 2, wherein the thermally conductive silicone grease composition contains gallium and / or a gallium alloy.
4. The thermally conductive silicone grease composition is
   (A) Organopolysiloxane having two or more alkenyl groups bonded to silicon atoms in one molecule: 100 parts by mass
   (B) Organohydrogenpolysiloxane having two or more hydrogen atoms bonded to a silicon atom in one molecule: Hydrogen bonded to a silicon atom in the component for one alkenyl group in the component (A) The amount that the number of atoms is 0.1-5.0,
   (C) Gallium having a melting point of 0 to 70 ° C. and / or its alloy: 1,000 to 20,000 parts by mass,
   (D) Thermally conductive filler having an average particle size of 0.1 to 100 μm: 0 to 1,000 parts by mass
   (E) Platinum-based catalyst: 0.1 to 500 ppm relative to the mass of component (A), and (G) the following general formula (1)
   

   

   Wherein R ¹ is the same or different monovalent hydrocarbon group, R ² is an alkyl group, an alkenyl group or an acyl group, a is an integer of 5 to 100, and b is 1 to 3 (It is an integer.)
   The semiconductor device according to any one of claims 1 to 3, comprising: 0 to 500 parts by mass of polysiloxane represented by:
5. Further, (G-2) the following general formula (2):
   R ³ _c R ⁴ _d Si (OR ⁵ ) _4-cd (2)
   Wherein R ³ is independently an alkyl group having 6 to 15 carbon atoms, R ⁴ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and R ⁵ is independently And an alkyl group having 1 to 6 carbon atoms, c is an integer of 1 to 3, d is an integer of 0 to 2, and the sum of c + d is an integer of 1 to 3.)
   The semiconductor device according to claim 4, wherein the alkoxysilane compound represented by the formula (A) is contained in an amount of 0.1 to 100 parts by mass with respect to 100 parts by mass of the component (A).
6. 6. The semiconductor device according to claim 2, wherein the curable resin composition contains 10 to 90% by volume of a filler.
7. 7. The semiconductor device according to claim 2, wherein the binder of the curable resin composition is silicone.
8. The thermally conductive silicone grease composition is placed on the exothermic electronic component, and the curable resin composition before curing is applied on the substrate so as to surround the exothermic electronic component seamlessly. The method according to any one of claims 2 to 7, further comprising a step of covering the electronic component and the applied curable resin composition before curing with a heat radiating member and then heating at 80 to 180 ° C. Semiconductor device manufacturing method.
   
   
   
   

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