Thermally conductive silicone grease and its manufacturing method, and chip assembly

Abstract

The present application provides a thermally conductive silicone grease obtained by uniformly mixing a plurality of raw material components, the plurality of raw material components including 1 to 50 parts by mass of a base silicone oil, 60 to 98 parts by mass of a thermally conductive filler, and 0.02 to 1 part by mass of a silicone oil crosslinking agent. The present application further provides a method for producing the thermally conductive silicone grease, and a chip assembly.

Description

[Technical field]

[0001] This application relates to the field of thermally conductive interface materials. [Background technology]

[0002] In electronic products (e.g., communication products), a heat sink can be used to dissipate heat from a chip, and a thermally conductive layer formed by a thermally conductive interface material (e.g., thermally conductive silicone grease) can be installed at the contact interface between the chip and the heat sink to smoothly transfer the heat emitted from the chip to the heat sink. Summary of the Invention [Means for solving the problem]

[0003] The present application provides a thermally conductive silicone grease and a method for producing the same, and a chip assembly.

[0004] In a first aspect, an embodiment of the present application provides a thermally conductive silicone grease comprising a plurality of raw material components uniformly mixed, the plurality of raw material components including 1 to 50 parts by mass of a base silicone oil, 60 to 98 parts by mass of a thermally conductive filler, and 0.02 to 1 part by mass of a silicone oil crosslinking agent. Furthermore, according to an embodiment of the present application, the thermally conductive filler includes first spherical metal particles having a first particle size of 5 to 30 μm and a mass percentage content in the thermally conductive filler of 40 to 60%, second spherical metal particles having a second particle size of 1 to 4 μm and a mass percentage content in the thermally conductive filler of 20 to 30%, and spherical zinc oxide particles having a third particle size of 0.1 to 0.5 μm and a mass percentage content in the thermally conductive filler of 10 to 30%.

[0005] According to an embodiment of the present application, the silicone oil cross-linking agent comprises hydrogen-containing silicone oil.

[0006] According to an embodiment of the present application, the mass percentage content of hydrogen in the hydrogen-containing silicone oil is 0.05-0.3%.

[0007] According to an embodiment of the present application, the raw material components include 0.01 to 0.5 parts by mass of a catalyst and 0.001 to 0.5 parts by mass of an inhibitor.

[0008] According to an embodiment of the present application, the catalyst includes chloroplatinic acid, and the inhibitor includes one or more of alkynol, vinyl-terminated silicone oil, maleic ester, organic amine, and heavy metal ion compound.

[0010] According to an embodiment of the present application, each of the first spherical metal particles and the second spherical metal particles includes one or more of spherical aluminum particles and spherical silver particles.

[0011] According to an embodiment of the present application, the base silicone oil includes one or more of dimethyl silicone oil, methylphenyl silicone oil, vinyl silicone oil, amino silicone oil, and methyl long-chain alkyl silicone oil.

[0012] According to an embodiment of the present application, the viscosity of the base silicone oil is 30 to 2000 cps.

[0013] In a second aspect, an embodiment of the present application provides a method for producing thermally conductive silicone grease, comprising the step of uniformly mixing all raw material components of the thermally conductive silicone grease to obtain the thermally conductive silicone grease, the raw material components of the thermally conductive silicone grease comprising 1 to 50 parts by mass of a base silicone oil, 60 to 98 parts by mass of a thermally conductive filler, and 0.02 to 1 part by mass of a silicone oil cross-linking agent. Furthermore, according to an embodiment of the present application, the thermally conductive filler includes first spherical metal particles having a first particle size of 5 to 30 μm and a mass percentage content in the thermally conductive filler of 40 to 60%, second spherical metal particles having a second particle size of 1 to 4 μm and a mass percentage content in the thermally conductive filler of 20 to 30%, and spherical zinc oxide particles having a third particle size of 0.1 to 0.5 μm and a mass percentage content in the thermally conductive filler of 10 to 30%.

[0015] According to an embodiment of the present application, the step of uniformly mixing all the raw material components of the thermal conductive silicone grease includes the steps of adding the first spherical metal particles and the second spherical metal particles to the base silicone oil, and stirring and dispersing to obtain a first intermediate product; adding the spherical zinc oxide particles to the first intermediate product, and stirring and dispersing to obtain a second intermediate product; and adding the silicone oil crosslinker to the second intermediate product, and stirring and dispersing to form the thermal conductive silicone grease.

[0016] According to an embodiment of the present application, the step of uniformly mixing all ingredients of the thermally conductive silicone grease comprises uniformly mixing all ingredients of the thermally conductive silicone grease in a double planetary mixer.

[0017] In a third aspect, an embodiment of the present application provides a chip assembly including a chip, a heat sink, and a thermally conductive layer filled between the chip and the heat sink, the thermally conductive layer being formed by curing any of the thermally conductive silicone greases described above. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a flow chart of a method for producing thermally conductive silicone grease according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a detailed flow chart of a method for producing the thermally conductive silicone grease according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a detailed flow chart of a method for producing a thermally conductive silicone grease according to another embodiment of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] In order to enable those skilled in the art to better understand the technical solution of the present application, the following detailed description will be given in conjunction with the accompanying drawings to explain the thermal conductive silicone grease and its manufacturing method and chip assembly provided in the embodiments of the present application. The present application will be described more fully below with reference to the drawings, but the exemplary embodiments may be embodied in different forms and the present application should not be construed as being limited to the embodiments described below. On the contrary, the purpose of providing these embodiments is to make the disclosure clear and complete, and to fully convey the scope of the present application to those skilled in the art. The drawings of the embodiments of the present application are provided for a better understanding of the embodiments of the present application, constitute a part of the specification, and are for explaining the present application together with the detailed embodiments, and do not constitute limitations on the present application. The above and other features and advantages will become more apparent to those skilled in the art by describing the detailed embodiments with reference to the drawings. Where not inconsistent, the embodiments and features of the embodiments of the present application may be combined with each other. The terms used herein are for the purpose of describing particular embodiments only and are not intended to be limiting of the present application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. As used herein, the singular forms "a," "an," and "the" are intended to include the plural unless the context clearly indicates otherwise. As used herein, the terms "comprising," "formed by," and "including" indicate the presence of said features, wholes, steps, operations, components, and / or assemblies but do not exclude the presence or addition of one or more other features, wholes, steps, operations, components, assemblies, and / or groups thereof. Unless otherwise specified, the meaning of all terms (including technical and scientific terms) used in this application is the same as that commonly understood by those skilled in the art. For example, terms defined in a common dictionary should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and this disclosure, and are not interpreted as having an idealized or excessively formal meaning unless the present application is expressly so limited.

[0020] (technical term) Unless otherwise specified, the following technical terms in the examples of this application shall be understood as follows: Bonding Line Thickness (BLT) refers to the minimum bond thickness, i.e., the smallest thickness that the thermally conductive material can form in use. Coefficient of Thermal Expansion (CTE) mismatch refers to the phenomenon in which different structures have different thermal expansion coefficients, causing relative deformation after being exposed to heat. Pump-out refers to the phenomenon in which the thermally conductive material is forced out from between the chip and the heat sink, forming a cavity. @30 psi indicates that the corresponding data is at "30 pounds per square inch pressure." The mass (weight) percentage of A in B means that A is a part of B, and refers to the relative percentage of the mass of A in B when the total mass of B (including A) is 100%. Spherical metal particles / spherical zinc oxide particles refer to the metal particles and zinc oxide particles used in the thermal conductive filler that are generally spherical or approximately spherical in shape, and do not mean that the specific shape of each particle is a perfect sphere.

[0021] (Specific embodiment) With the development of technology (for example, the development of 5G communication technology), the power consumption of chips has increased significantly, their dimensions have become larger, their heat flow density has increased, and the packaging method of chips has also developed from 2D (two-dimensional) to 2.5D and even 3D (three-dimensional), and from covered (packaged) chips to bare (unpackaged) chips. With these changes, deformation such as chip warping has become an increasingly serious problem. The increasing heat flow density and deformation of chips place higher demands on the thermal performance and reliability of the thermally conductive interface materials they use. Thermally conductive silicone grease has the advantages of low thermal resistance, low BLT, and stencil printing, and is therefore used as a thermally conductive interface material between chips and heat sinks in some related technologies. However, some thermally conductive silicone greases lack strength and are prone to deformation, so when used for large objects or bare chips, deformation due to the CTE mismatch of different structures can cause pump-out and dripping problems in the thermally conductive silicone grease (i.e., leakage of the thermally conductive silicone grease), making it unable to meet the demand for reliability. In another related technology, two-component thermal conductive gel is also a kind of thermal conductive material. However, the thermal conductive gel has high viscosity and excessive BLT, which is usually more than 0.2 mm, and cannot meet the requirements of stencil printing technology. In addition, the thermal resistance is high, which is usually less than 0.3°C cm 2 / W@30psi or higher, it can only be used as a point bonding material and not as a thermally conductive interface material between a chip and a heat sink (especially not for thin thermally conductive layers on large chips). An embodiment of the present application provides a thermally conductive silicone grease obtained by uniformly mixing a plurality of raw material components, the plurality of raw material components including 1 to 50 parts by mass of base silicone oil, 60 to 98 parts by mass of a thermally conductive filler, and 0.02 to 1 part by mass of a silicone oil crosslinking agent. The thermally conductive silicone grease according to the embodiment of the present application is not a "two-component" product, but a whole product, since it is composed of multiple homogeneously mixed raw material components, and the raw material components do not contain solvents, so it is a directly usable non-solvent product. The base silicone oil is a silicone oil as a base component in the thermally conductive silicone oil, the silicone oil cross-linking agent can cross-link the base silicone oil, and the thermally conductive filler is a filler that has a thermally conductive effect. The thermally conductive silicone grease according to the embodiment of the present application is a single-component thermally conductive silicone grease, not a two-component thermally conductive gel, and does not contain a solvent. Therefore, it has low viscosity, good thixotropy, small BLT, and can be used for stencil printing, and can be used as a thermally conductive interface material between a chip and a heat sink. The thermal conductive silicone grease according to the embodiment of the present application contains a silicone oil cross-linking agent, so after the thermal conductive silicone grease hardens, the base silicone oil molecules are no longer in a linear short-chain form, but are cross-linked to form a mesh, which significantly improves strength (including cohesive strength and adhesive strength). Therefore, there are no pump-out or dripping problems even in deterioration tests of large bare die chips, and the reliability is high. Through testing, the performance of the thermal conductive silicone grease according to the embodiment of this application can reach the following: Thermal conductivity > 5 W / mK (measured by Hotdisk method), thermal resistance ≦ 0.07°C cm 2 / W@30psi (measured based on ASTM D5470 standard), BLT≦0.03mm@30psi (measured based on ASTM D 5470 standard), oil permeability 0.01% (measured after 24 hours at 200℃), volatile content 0.2% (measured after 24 hours at 200℃), no pumps or drips in degradation test (thermal conductive silicone grease is used on a large bare die chip and cycled 200 times at -40 to 125℃, then tested). Shore hardness (Shore 00) measured after degradation test or after baking at 125℃ for 30 min is 30 to 70. According to an embodiment of the present application, the silicone oil crosslinker comprises a hydrogen-containing silicone oil. According to the embodiment of the present application, the mass percentage content of hydrogen in the hydrogen-containing silicone oil is 0.05-0.3%. According to the embodiment of the present application, hydrogen-containing silicone oil (for example, hydrogen-containing silicone oil having a mass percentage content of hydrogen of 0.05 to 0.3%) can be used as the silicone oil crosslinking agent. According to an embodiment of the present application, the hydrogen-containing silicone oil includes one or more of terminal hydrogen-containing silicone oil and side hydrogen-containing silicone oil. According to the embodiment of the present application, the raw material components further contain 0.01 to 0.5 parts by mass of a catalyst and 0.001 to 0.5 parts by mass of an inhibitor. According to an embodiment of the present application, the catalyst includes chloroplatinic acid, and the inhibitor includes one or more of an alkynol, a vinyl-terminated silicone oil, a maleic acid ester, an organic amine, and a heavy metal ion compound. According to the examples of the present application, the platinum content in chloroplatinic acid is 1000 to 5000 ppm. When containing silicone oil crosslinking agent, the use of a catalyst can accelerate the crosslinking reaction, and the use of an inhibitor can avoid undesirable or too fast reaction. According to the embodiment of the present application, the particle size of the thermally conductive filler is 0.1 to 50 μm. According to an embodiment of the present application, the thermally conductive filler includes first spherical metal particles having a first particle size of 5 to 30 μm and a mass percentage content in the thermally conductive filler of 40 to 60%, second spherical metal particles having a second particle size of 1 to 4 μm and a mass percentage content in the thermally conductive filler of 20 to 30%, and spherical zinc oxide particles having a third particle size of 0.1 to 0.5 μm and a mass percentage content in the thermally conductive filler of 10 to 30%. The thermally conductive filler according to the embodiment of the present application includes three types of spherical particles of specific particle diameters and specific materials, namely, spherical metal particles having a particle diameter of 5-30 μm and a mass percentage content of 40-60 wt%, spherical metal particles having a particle diameter of 1-4 μm and a mass percentage content of 20-30 wt%, and spherical zinc oxide particles having a particle diameter of 0.1-0.5 μm and a mass percentage content of 10-30 wt%. By using a thermally conductive filler containing spherical particles of the specific particle size and material described above, the thermal resistance of the thermally conductive silicone grease of the embodiments of the present application can be further reduced and its thermal conductivity performance (e.g., K value) can be improved, thereby satisfying the heat dissipation requirements of large, high-power chips. According to an embodiment of the present application, the spherical metal particles include one or more of spherical aluminum particles and spherical silver particles. The spherical metal particles according to the embodiment of the present application can be selected from spherical aluminum particles (aluminum powder) and spherical silver particles (silver powder). For example, it can be spherical aluminum particles (aluminum powder), because it is relatively inexpensive and can form a thin alumina layer on its surface, so that the electrical conductivity is not very high. According to the embodiments of the present application, in addition to the spherical particles of the specific particle size and specific material described above, the thermally conductive filler may contain any one or more of magnesium oxide particles, aluminum nitride particles, silicon nitride particles, boron nitride particles, carbon fibers, diamond particles, and copper powder, and the particle size of these components may be 0.1 to 50 μm. According to the embodiment of the present application, the raw material components further include 0.01 to 10 parts by mass of a filler treatment agent. According to an embodiment of the present application, the filler treating agent includes one or more of a silane coupling agent, stearic acid, titanic acid ester, and aluminum acid ester. According to the embodiment of the present application, the use of a filler treatment agent can improve the distribution state of the thermally conductive filler. According to an embodiment of the present application, the base silicone oil includes one or more of dimethyl silicone oil, methylphenyl silicone oil, vinyl silicone oil, amino silicone oil, and methyl long-chain alkyl silicone oil. According to the embodiment of the present application, the viscosity of the base silicone oil is 30 to 2000 cps. According to the embodiments of the present application, the selection of the components and viscosity of the base silicone oil can ensure that the entire thermal conductive silicone grease has low viscosity and good thixotropy, so that it can be used for stencil printing and has a relatively low BLT. According to embodiments of the present application, the ingredients further include one or more of a color paste, a flame retardant, a thixotropic agent, and a thickening agent (eg, a tackifying resin). In addition to the raw material components described above, the raw material components may contain various conventional additives, which will not be described in detail here. An embodiment of the present application provides a method for making a thermally conductive silicone grease. 1 is a flow chart of a method for producing a thermal conductive silicone grease according to an embodiment of the present application. Referring to FIG. 1, the method for producing a thermal conductive silicone grease according to an embodiment of the present application includes step S001. In step S001, all the raw material components of the thermally conductive silicone grease are uniformly mixed to obtain the thermally conductive silicone grease. The raw material components of the thermally conductive silicone grease include 1 to 50 parts by mass of base silicone oil, 60 to 98 parts by mass of a thermally conductive filler, and 0.02 to 1 part by mass of a silicone oil crosslinking agent.

[0022] According to an embodiment of the present application, the thermally conductive filler includes first spherical metal particles having a first particle size of 5 to 30 μm, the mass percentage content of the thermally conductive filler being 40 to 60%, and the mass percentage content of the thermally conductive filler being 20 to 30%, and 2 A second spherical metal particle having a second particle size of 1 to 4 μm and a mass percentage content in the thermal conductive filler of 10 to 30%, 3 and a third particle size of spherical zinc oxide particles having a particle size of 0.1 to 0.5 μm.

[0023] The manufacturing method according to the embodiment of the present application is for manufacturing the above-mentioned thermally conductive silicone grease, and it is necessary to mix each of the raw material components uniformly. Fig. 2 is a detailed flowchart of a method for producing thermally conductive silicone grease according to an embodiment of the present application. The detailed flowchart shown in Fig. 2 is a detailed flow of step S001 shown in Fig. 1. Referring to Fig. 2, uniformly mixing all raw material components of the thermally conductive silicone grease (step S001) includes steps S0011 to S0013. In step S0011, spherical metal particles having a first particle size and spherical metal particles having a second particle size are added to a base silicone oil, and a first intermediate product is obtained by stirring and dispersing the mixture. In step S0012, spherical zinc oxide particles having a third particle size are added to the first intermediate product obtained in step S0011, and the mixture is stirred and dispersed to obtain a second intermediate product. In step S0013, a silicone oil cross-linking agent is added to the second intermediate product obtained in step S0012, and the mixture is stirred and dispersed to form a thermally conductive silicone grease. According to the embodiment of the present application, when the above raw material components are mixed, the base silicone oil (which may contain a filler treatment agent) is used as the base, and spherical metal particles are first added thereto and stirred and dispersed, then spherical zinc oxide particles are added thereto and stirred and dispersed, and then the silicone oil crosslinking agent (which may contain an inhibitor) is added. If necessary, a catalyst can also be added last. According to an embodiment of the present application, uniformly mixing all the raw ingredients of the heat conductive silicone grease (step S001) includes a step of uniformly mixing all the raw ingredients of the heat conductive silicone grease in a double planetary mixer. The double planetary mixer in the present application is merely an example, and the present application is not limited thereto, and any device capable of uniformly mixing all the raw ingredients can be used. According to the embodiment of the present application, since the above-mentioned raw material components can be mixed using a double planetary mixer, the production of the heat conductive silicone grease can be carried out using one device (e.g., a double planetary mixer) and there is no need to use multiple devices (e.g., a grinder or a vacuum kneader), so the production process is simple and the cost is low. 3 is a flow chart of a method for producing a thermally conductive silicone grease according to another embodiment of the present application. Referring to FIG. 3, the method for producing a thermally conductive silicone grease according to the embodiment of the present application may include steps S101 to S106. In step S101, the above-mentioned base silicone oil and filler treatment agent are added in order to the double planetary mixer. In step S102, the spherical metal particles (thermal conductive filler) having different particle sizes are added in sequence to the double planetary mixer and stirred and dispersed. The stirring time is 10 to 60 min, the stirring speed is 20 to 50 r / min, and the dispersion speed is 350 to 900 r / min. In step S103, the above-mentioned spherical zinc oxide (thermal conductive filler) is added to the double planetary mixer and stirred and dispersed. The stirring and dispersion time is 10 to 60 min, the stirring speed is 20 to 50 r / min, and the dispersion speed is 350 to 900 r / min. In step S104, the above-mentioned inhibitor and silicone oil cross-linking agent are added in order to the double planetary mixer, and the mixture is stirred and dispersed, followed by evacuation. The stirring and dispersion time is 10 to 60 min, the stirring speed is 20 to 50 r / min, the dispersion speed is 350 to 900 r / min, and the degree of vacuum is -0.096 to -0.1 MPa. In step S105, the above catalyst is added to a double planetary mixer, and the mixture is stirred and dispersed, followed by evacuation. The stirring and dispersion time is 10 to 60 min, the stirring speed is 20 to 50 r / min, the dispersion speed is 350 to 900 r / min, and the degree of vacuum is -0.096 to -0.1 MPa. In step S106, the above product is cooled and then transferred to an extruder, and the extrudate is extruded to obtain the thermally conductive silicone grease of the embodiment of the present application. An embodiment of the present application provides a chip assembly including a chip, a heat sink, and a thermally conductive layer filled between the chip and the heat sink, the thermally conductive layer being formed by curing any one of the thermally conductive silicone greases described above. A chip assembly according to an embodiment of the present invention includes a chip and a heat sink, and a thermally conductive layer formed between the chip and the heat sink by hardening the thermally conductive silicone grease. The application types and forms of the chip assemblies according to the embodiments of the present invention are diverse. For example, the above chip assemblies may be carrier device chips, fixed network chips, server chips, computer chips, etc. For example, the above chip assembly formats may be: (1) spring screw type heat sink or push type heat sink + bare chip or chip with cover; (2) chip + screwed hard contact housing (heat sink). The above chip assembly may be in the form of "large, high power consumption chip + thin thermal conductive layer". According to an embodiment of the present application, for example, the raw material components for producing the thermally conductive silicone grease are 6 parts by mass of a base silicone oil, which is a vinyl silicone oil and has a viscosity of 100 cps; 85 parts by mass of a thermally conductive filler, which is composed of spherical aluminum particles having a particle size of 10 μm, spherical aluminum particles having a particle size of 2 μm, and spherical zinc oxide particles having a particle size of 0.3 μm, and the mass percentage contents of the spherical aluminum particles having a particle size of 10 μm, the spherical aluminum particles having a particle size of 2 μm, and the spherical zinc oxide particles having a particle size of 0.3 μm are 50%, 28%, and 22%, respectively; and a filler which is octyltrimethoxysilane (a silane coupling agent). The catalyst may include 0.2 parts by mass of a chromium treating agent, 0.35 parts by mass of a silicone oil crosslinking agent which is a mixture of terminal hydrogen-containing silicone oil and side hydrogen-containing silicone oil having a hydrogen mass percentage content of 0.1% and a mass ratio of the terminal hydrogen-containing silicone oil to the side hydrogen-containing silicone oil of 1:2.5, 0.1 parts by mass of a catalyst which is chloroplatinic acid and has a platinum mass content of 3000 ppm, and 0.01 parts by mass of an inhibitor which is 1-ethynyl-1-cyclohexanol. According to an embodiment of the present application, for example, the manufacturing method of the thermal conductive silicone grease may include the following steps: Step A101: Add base silicone oil and filler treatment agent to the double planetary mixer in sequence. Step A102: Add spherical aluminum particles with a particle size of 10 μm and spherical aluminum particles with a particle size of 2 μm in sequence to the double planetary mixer, and stir and disperse for 15 minutes. The stirring speed is 25 r / min, and the dispersion speed is 600 r / min. Step A103: Add spherical zinc oxide particles with a particle size of 0.3 μm in sequence to the double planetary mixer, and stir and disperse for 30 minutes, the stirring speed is 25 r / min, and the dispersion speed is 600 r / min. Step A104: Add inhibitor and silicone oil crosslinking agent in sequence to the double planetary mixer, and stir and disperse and evacuate for 15 minutes, the stirring speed is 25 r / min, the dispersion speed is 600 r / min, and the vacuum degree is -0.097 MPa. Step A105: Add the catalyst to the double planetary mixer, and perform stirring and dispersion and evacuation for 30 minutes, the stirring speed is 25 r / min, the dispersion speed is 600 r / min, and the vacuum degree is -0.097 MPa. Step A106: Transfer the product to an extruder, and extrude the extrudate into a can to obtain the thermal conductive silicone sample of this example. The thermal conductive silicone grease samples manufactured in steps A101 to A106 above were subjected to performance tests, and the results were as follows: Thermal conductivity: 5.5 W / mK (measured by the Hotdisk method), Thermal resistance: 0.05°C cm 2 / W@30psi (measured according to ASTM D 5470 standard), BLT: 0.02mm@30psi (measured according to ASTM D 5470 standard), Oil permeability: 0.01% (measured after 24h at 200℃), Volatile content: 0.2% (measured after 24h at 200℃), Degradation test: No pump, no dripping (Thermal conductive silicone grease is used on a large bare die chip and circulated 200 times at -40~125℃, then measured), Shore hardness (Shore 00): 40 (measured after baking at 125℃ for 30 min). According to an embodiment of the present application, for example, the raw material component for producing the thermal conductive silicone grease is dimethyl silicone oil, which has a viscosity of 1800 The thermal conductive filler may include 6 parts by mass of base silicone oil, which is cps; 95 parts by mass of a thermal conductive filler consisting of spherical aluminum particles having a particle size of 25 μm, spherical aluminum particles having a particle size of 1 μm, and spherical zinc oxide particles having a particle size of 0.5 μm, the mass percentage contents of the spherical aluminum particles having a particle size of 25 μm, the spherical aluminum particles having a particle size of 1 μm, and the spherical zinc oxide particles having a particle size of 0.5 μm being 40%, 30%, and 30%, respectively; 3 parts by mass of a filler treatment agent, which is a titanate ester; 1 part by mass of a silicone oil crosslinking agent, which is a mixture of a terminal hydrogen-containing silicone oil and a side hydrogen-containing silicone oil, the mass percentage content of which is 0.2%, and the mass ratio of the terminal hydrogen-containing silicone oil to the side hydrogen-containing silicone oil is 1:1; 0.01 parts by mass of a catalyst, which is chloroplatinic acid and has a platinum mass content of 5000 ppm; and 0.001 parts by mass of an inhibitor, which is a maleic acid ester. According to an embodiment of the present application, for example, the manufacturing method of the thermal conductive silicone grease may include the following steps: Step A201: Add base silicone oil and filler treatment agent to the double planetary mixer in sequence. Step A202: Add spherical aluminum particles with a particle size of 25 μm and spherical aluminum particles with a particle size of 1 μm in sequence to the double planetary mixer, and stir and disperse for 10 minutes, the stirring speed is 50 r / min, and the dispersion speed is 900 r / min. Step A203: Add spherical zinc oxide particles with a particle size of 0.5 μm in sequence to the double planetary mixer, and stir and disperse for 10 minutes, the stirring speed is 50 r / min, and the dispersion speed is 900 r / min. Step A204: Add inhibitor and silicone oil crosslinking agent in sequence to the double planetary mixer, and stir and disperse and evacuate for 20 minutes, the stirring speed is 50 r / min, the dispersion speed is 900 r / min, and the vacuum degree is -0.1 MPa. Step A205: Add the catalyst into the double planetary mixer, and carry out stirring and dispersion and evacuation for 20 minutes, the stirring speed is 50 r / min, the dispersion speed is 900 r / min, and the vacuum degree is -0.1 MPa. Step A206: Transfer the product to an extruder, and extrude the extrudate into a can to obtain the thermal conductive silicone grease sample of this example. The thermal conductive silicone grease samples manufactured in steps A201 to A206 above were subjected to performance tests, and the results are as follows: Thermal conductivity: 5.9 W / mK (measured by the Hotdisk method), Thermal resistance: 0.05°C cm 2 / W@30psi (measured according to ASTM D 5470 standard), BLT: 0.03mm@30psi (measured according to ASTM D 5470 standard), Oil permeability: 0.01% (measured after 24h at 200℃), Volatile content: 0.2% (measured after 24h at 200℃), Degradation test: No pump, no dripping (Thermal conductive silicone grease is used on a large bare die chip and circulated 200 times at -40~125℃, then measured), Shore hardness (Shore 00): 70 (measured after baking at 125℃ for 30 min).

[0024] According to an embodiment of the present application, for example, the raw material components for producing the thermally conductive silicone grease are dimethyl silicone oil, and are composed of 45 parts by mass of a base silicone oil having a viscosity of 300 cps, spherical aluminum particles having a particle size of 20 μm, spherical aluminum particles having a particle size of 4 μm, and spherical zinc oxide particles having a particle size of 0.5 μm. 20 Spherical aluminum particles with diameter of μm 4 Spherical aluminum particles with diameter of μm 0.5 The filler may include 60 parts by mass of a thermally conductive filler having mass percentage contents of 60%, 20%, and 20% of spherical zinc oxide particles of 1 μm, respectively, 8 parts by mass of a filler treatment agent which is an aluminum acid ester, 0.5 parts by mass of a silicone oil crosslinker which is a mixture of terminal hydrogen-containing silicone oil and side end hydrogen-containing silicone oil having a hydrogen mass percentage content of 0.3% and a mass ratio of the terminal hydrogen-containing silicone oil to the side end hydrogen-containing silicone oil of 1:0.8, 0.5 parts by mass of a catalyst which is chloroplatinic acid and has a platinum mass content of 1000 ppm, and 0.5 parts by mass of an inhibitor which is a vinyl silicone oil at both ends.

[0025] According to an embodiment of the present application, for example, a method for producing a heat conductive silicone grease may include the following steps: Step A301: Add base silicone oil and filler treatment agent to a double planetary mixer in sequence. Step A302: Add spherical aluminum particles with a particle size of 20 μm and spherical aluminum particles with a particle size of 4 μm in sequence to a double planetary mixer, and stir and disperse for 50 min, with a stirring speed of 20 r / min and a dispersion speed of 400 r / min. Step A303: Add spherical aluminum particles with a particle size of 20 μm and 4 μm in sequence to a double planetary mixer, and disperse for 50 min, with a stirring speed of 20 r / min and a dispersion speed of 400 r / min. 0.5 Add 1 μm spherical zinc oxide particles in sequence, and stir and disperse for 45 minutes, stirring speed is 20 r / min, dispersion speed is 400 r / min. Step A304: Add inhibitor and silicone oil crosslinking agent in sequence to the double planetary mixer, stir and disperse and evacuate for 45 minutes, stirring speed is 20 r / min, dispersion speed is 400 r / min, and vacuum degree is -0.1 MPa. Step A305: Add catalyst to the double planetary mixer, stir and disperse and evacuate for 50 minutes, stirring speed is 20 r / min, dispersion speed is 400 r / min, and vacuum degree is -0.1 MPa. Step A306: Transfer the product to the extruder, and extrude the extrudate into a can to obtain the heat conductive silicone grease sample of this example.

[0026] The thermal conductive silicone grease samples manufactured in steps A301 to A306 above were subjected to performance tests, and the results are as follows: Thermal conductivity: 5.2 W / mK (measured by Hotdisk method), Thermal resistance: 0.07°C·cm2 / W@30psi (measured according to ASTM D 5470), BLT: 0.02mm@30psi (measured according to ASTM D 5470), Oil permeability: 0.01% (measured after 24 h at 200°C), Volatile content: 0.2% (measured after 24 h at 200°C), Degradation test: No pump, no dripping (The thermal conductive silicone grease was applied to a large bare die chip, circulated 200 times at -40 to 125°C, and then measured), Shore hardness (Shore 00): 55 (measured after baking at 125°C for 30 min). Although exemplary embodiments are disclosed herein and specific terms are employed, they should be used and interpreted in a general illustrative sense only and not for limiting purposes. In some instances, it will be apparent to those skilled in the art that, unless expressly indicated otherwise, features, characteristics and / or elements described in combination with a particular embodiment may be used alone or features, characteristics and / or elements described in combination with other embodiments may be used in combination. Thus, those skilled in the art will appreciate that various changes in form and detail may be made without departing from the scope of the present application as set forth in the appended claims.

Claims

1. A thermally conductive silicone grease comprising a plurality of raw material components uniformly mixed, the plurality of raw material components comprising: 1 to 50 parts by weight of a base silicone oil; 60 to 98 parts by weight of a thermally conductive filler; 0.02 to 1 parts by weight of a silicone oil crosslinker; The thermally conductive filler is The mass percentage content in the thermally conductive filler is 40 to 60%, and the first spherical metal particles have a first particle size of 5 to 30 μm; A mass percentage content of the thermally conductive filler is 20 to 30%, and the first particle size is 1 to 4 μm. The mass percentage content in the thermally conductive filler is 10 to 30%, and the first particle size is 0.1 to 0.5 μm. Thermally conductive silicone grease.

2. The silicone oil crosslinking agent comprises a hydrogen-containing silicone oil The thermally conductive silicone grease according to claim 1.

3. The mass percentage content of hydrogen in the hydrogen-containing silicone oil is 0.05-0.3%. The thermally conductive silicone grease according to claim 2.

4. The plurality of raw material components are 0.01 to 0.5 parts by weight of a catalyst; 0.001 to 0.5 parts by weight of an inhibitor; and The thermally conductive silicone grease according to claim 1.

5. The catalyst comprises chloroplatinic acid; The inhibitor includes one or more of alkynol, vinyl-terminated silicone oil, maleic acid ester, organic amine, and heavy metal ion compound. The thermally conductive silicone grease according to claim 4.

6. Each of the first spherical metal particles and the second spherical metal particles includes one or more of spherical aluminum particles and spherical silver particles. The thermally conductive silicone grease according to claim 1.

7. The base silicone oil includes one or more of dimethyl silicone oil, methylphenyl silicone oil, vinyl silicone oil, amino silicone oil, and methyl long-chain alkyl silicone oil. The thermally conductive silicone grease according to claim 1.

8. The viscosity of the base silicone oil is 30 to 2000 cps. The thermally conductive silicone grease according to claim 1.

9. The method includes the steps of: uniformly mixing all the raw material components of the thermal conductive silicone grease to obtain the thermal conductive silicone grease; The raw material components of the thermal conductive silicone grease are: 1 to 50 parts by weight of a base silicone oil; 60 to 98 parts by weight of a thermally conductive filler; 0.02 to 1 parts by weight of a silicone oil crosslinker; The thermally conductive filler is The mass percentage content in the thermally conductive filler is 40 to 60%, and the first spherical metal particles have a first particle size of 5 to 30 μm; A mass percentage content of the thermally conductive filler is 20 to 30%, and the first particle size is 1 to 4 μm. The mass percentage content in the thermally conductive filler is 10 to 30%, and the first particle size is 0.1 to 0.5 μm. How to make thermally conductive silicone grease.

10. The step of uniformly mixing all the raw ingredients of the thermal conductive silicone grease includes: adding the first spherical metal particles and the second spherical metal particles to the base silicone oil, and stirring and dispersing the particles to obtain a first intermediate product; adding the spherical zinc oxide particles to the first intermediate product, and stirring and dispersing the particles to obtain a second intermediate product; adding the silicone oil cross-linking agent to the second intermediate product, and stirring and dispersing the silicone oil cross-linking agent to form the thermal conductive silicone grease; The method of claim 9.

11. The step of uniformly mixing all the raw ingredients of the thermal conductive silicone grease includes: The method includes the step of uniformly mixing all the ingredients of the thermal conductive silicone grease in a double planetary mixer. The method according to claim 9 or 10.

12. Chip and A heat sink; a thermally conductive layer disposed between the chip and the heat sink; The thermally conductive layer is formed by curing the thermally conductive silicone grease according to any one of claims 1 to 8. Chip assembly.

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