Silicon nitride-based composite ceramic substrate and preparation method thereof

Abstract

The present invention relates to the technical field of ceramic substrate materials, and in particular to a silicon nitride-based composite ceramic substrate and a preparation method thereof. The silicon nitride-based composite ceramic substrate is composed of the following raw materials: 95-110 parts of silicon nitride, 4-8 parts of boron nitride whiskers, 7-14 parts of potassium hexatitanate whiskers, 22-38 parts of sintering aids, 14-20 parts of plasticizers, 6-15 parts of dispersants, 16-25 parts of binders, and 85-115 parts of organic solvents. By adding titanium carbonitride and zirconium tungstate to the silicon nitride-based substrate material, the present invention can not only improve the mechanical properties of the silicon nitride-based ceramic substrate, such as flexural strength and fracture toughness, but also further improve the bonding strength of the silicon nitride-based ceramic substrate to various metals such as titanium, nickel, and aluminum, thereby improving the overall reliability of the ceramic substrate.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramic substrate materials, and in particular to a silicon nitride-based composite ceramic substrate and a preparation method thereof. Background Art

[0002] In recent years, semiconductor devices have experienced rapid development, driven by higher power, higher frequency, and greater integration. The semiconductor processes and microelectronics technologies required to support this growth have also advanced rapidly. For example, integrated circuits (ICs) have become increasingly integrated, with increasing wiring density. This has led to the emergence of heat dissipation issues within electronic packaging substrates. Heat generated by semiconductor devices during operation is a key factor in their failure, and the thermal conductivity of the insulating substrate is crucial for dissipating heat throughout the device. If the substrate cannot effectively and promptly dissipate heat from the various components within the IC, significant amounts of heat will accumulate within the IC, ultimately causing device damage. Solving this substrate heat dissipation problem can be achieved by increasing its thermal conductivity and reducing its thickness. However, given the high mechanical properties required for the substrate in its operating environment, the substrate material must possess both high thermal conductivity and excellent mechanical properties.

[0003] Silicon nitride (Si3N4) ceramics, as advanced structural ceramics, offer excellent properties such as high temperature resistance, high strength, high toughness, high hardness, creep resistance, oxidation resistance, and wear resistance. They also possess excellent thermal shock resistance and dielectric properties, high thermal conductivity, and excellent high-frequency electromagnetic wave transmission performance. These excellent overall properties make them particularly attractive and promising for substrate applications. Furthermore, the surface metallization process for ceramic substrates is crucial for enabling the use of ceramics in power electronic component packaging. The metallization method determines the performance, manufacturing cost, product yield, and scope of application of the ceramic substrate.

[0004] Based on the above situation, the present invention proposes a silicon nitride-based composite ceramic substrate and a preparation method thereof, which can effectively solve the above problems. Summary of the Invention

[0005] The object of the present invention is to provide a silicon nitride-based composite ceramic substrate and a preparation method thereof.

[0006] To achieve the above objectives, the present invention provides a silicon nitride-based composite ceramic substrate, which is composed of the following raw materials: 95-110 parts of silicon nitride, 4-8 parts of boron nitride whiskers, 7-14 parts of potassium hexatitanate whiskers, 22-38 parts of a sintering aid, 14-20 parts of a plasticizer, 6-15 parts of a dispersant, 16-25 parts of a binder, and 85-115 parts of an organic solvent.

[0007] Preferably, the sintering aid is a rare earth oxide, including at least one or a combination of two or more of yttrium oxide, calcium oxide, niobium oxide, cerium oxide, samarium oxide, and lanthanum oxide.

[0008] Preferably, the plasticizer includes at least one of dibutyl phthalate and glycerol, or a combination of two or more thereof.

[0009] Preferably, the dispersant includes at least one of triolein, triethyl phosphate, sodium polyacrylate, polyacrylate, and castor oil, or a combination of two or more thereof.

[0010] Preferably, the binder is at least one of polyvinyl butyral, acrylate, and polyvinyl alcohol, or a combination of two or more thereof.

[0011] Preferably, the organic solvent includes at least one of anhydrous ethanol, acetone, isopropyl alcohol, and ethyl acetate, or a combination of two or more thereof.

[0012] Preferably, the raw material of the silicon nitride-based composite ceramic substrate further includes a combination of zirconium tungstate and titanium carbonitride.

[0013] Preferably, the silicon nitride is β-silicon nitride with an average particle size of 1 μm, a specific surface area of ​​49 m2 / g, and a β-phase crystal phase; the titanium carbonitride has an average particle size of 3 μm and a specific surface area of ​​21 m2 / g; and the zirconium tungstate has an average particle size of 3 μm.

[0014] Preferably, the silicon nitride-based composite ceramic substrate is composed of the following raw materials: 95-110 parts of silicon nitride, 4-8 parts of boron nitride whiskers, 7-14 parts of potassium hexatitanate whiskers, 2-7 parts of titanium carbonitride, 6-12 parts of zirconium tungstate, 10-18 parts of yttrium oxide, 12-20 parts of lanthanum oxide, 14-20 parts of dibutyl phthalate, 6-15 parts of triolein, 16-25 parts of polyvinyl butyral, 50-65 parts of isopropyl alcohol, 25-30 parts of ethyl acetate, and 10-20 parts of anhydrous ethanol.

[0015] Preferably, the silicon nitride-based composite ceramic substrate is composed of the following raw materials: 100 parts of silicon nitride, 6 parts of boron nitride whiskers, 10 parts of potassium hexatitanate whiskers, 4 parts of titanium carbonitride, 9 parts of zirconium tungstate, 13 parts of yttrium oxide, 16 parts of lanthanum oxide, 18 parts of dibutyl phthalate, 8 parts of triolein, 22 parts of polyvinyl butyral, 60 parts of isopropyl alcohol, 30 parts of ethyl acetate, and 15 parts of anhydrous ethanol.

[0016] The present invention also provides a method for preparing a silicon nitride-based composite ceramic substrate, the method comprising the following steps:

[0017] (1) Silicon nitride, boron nitride whiskers, potassium hexatitanate whiskers, titanium carbonitride, zirconium tungstate, yttrium oxide, and lanthanum oxide were mixed evenly, and then isopropyl alcohol, triolein, ethyl acetate, and anhydrous ethanol were added. After mixing evenly, the mixture was ball-milled and dispersed for 18 to 20 hours to obtain a mixture A.

[0018] (2) Add dibutyl phthalate and polyvinyl butyral to mixture A, stir evenly, and then ball-mill for 10-12 hours to obtain mixture B;

[0019] (3) vacuum degassing the mixture B to obtain a casting slurry, and then performing casting molding to obtain a casting green sheet;

[0020] (4) Sintering the tape-cast green sheet obtained in step (3) in an inert atmosphere at a heating rate of 20 to 25°C / min to a temperature of 1850 to 1900°C and maintaining the temperature for 6 to 8 hours.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. By adding titanium carbonitride and zirconium tungstate to the silicon nitride-based substrate material, the present invention can not only improve the mechanical properties of the silicon nitride-based ceramic substrate, such as flexural strength and fracture toughness, but also further enhance the bonding strength of the silicon nitride-based ceramic substrate to various metals, such as titanium, nickel, and aluminum, thereby improving the overall reliability of the ceramic substrate.

[0023] 2. The raw materials of the present invention are sufficient in China and are reasonably priced, so that there is no high cost limit for large-scale production; secondly, the combination of the present invention has a wide range of applications and can meet the production requirements of the back adhesive layer of the silicon nitride-based composite ceramic substrate; at the same time, the preparation process is simple and the overall production cost is not high, which is conducive to large-scale industrial production. DETAILED DESCRIPTION

[0024] Example 1

[0025] Weigh the specific raw materials according to Table 1, and the remaining preparation steps are as follows:

[0026] (1) Silicon nitride, boron nitride whiskers, potassium hexatitanate whiskers, titanium carbonitride, zirconium tungstate, yttrium oxide, and lanthanum oxide were mixed uniformly, and then isopropyl alcohol, triolein, ethyl acetate, and anhydrous ethanol were added. After mixing uniformly, the mixture was ball-milled and dispersed for 18 hours to obtain a mixture A;

[0027] (2) Add dibutyl phthalate and polyvinyl butyral to mixture A, stir evenly, and then ball-mill for 10 hours to obtain mixture B;

[0028] (3) vacuum degassing the mixture B to obtain a casting slurry, and then performing casting molding to obtain a casting green sheet;

[0029] (4) Sintering the tape-cast green sheet obtained in step (3) in an inert atmosphere at a heating rate of 20°C / min to a temperature of 1850°C and maintaining the temperature for 8 hours to obtain the product.

[0030] Example 2

[0031] Weigh the specific raw materials according to Table 1, and the remaining preparation steps are as follows:

[0032] (1) Silicon nitride, boron nitride whiskers, potassium hexatitanate whiskers, titanium carbonitride, zirconium tungstate, yttrium oxide, and lanthanum oxide were mixed uniformly, and then isopropyl alcohol, triolein, ethyl acetate, and anhydrous ethanol were added, mixed uniformly, and ball-milled for 20 hours to obtain a mixture A;

[0033] (2) Add dibutyl phthalate and polyvinyl butyral to mixture A, stir evenly, and then ball-mill for 12 hours to obtain mixture B;

[0034] (3) vacuum degassing the mixture B to obtain a casting slurry, and then performing casting molding to obtain a casting green sheet;

[0035] (4) Sintering the tape-cast green sheet obtained in step (3) in an inert atmosphere at a heating rate of 25°C / min to a temperature of 1900°C and maintaining the temperature for 6 hours.

[0036] Example 3

[0037] Weigh the specific raw materials according to Table 1, and the remaining preparation steps are as follows:

[0038] (1) Silicon nitride, boron nitride whiskers, potassium hexatitanate whiskers, titanium carbonitride, zirconium tungstate, yttrium oxide, and lanthanum oxide were mixed uniformly, and then isopropyl alcohol, triolein, ethyl acetate, and anhydrous ethanol were added, mixed uniformly, and ball-milled for 20 hours to obtain a mixture A;

[0039] (2) Add dibutyl phthalate and polyvinyl butyral to mixture A, stir evenly, and then ball-mill for 12 hours to obtain mixture B;

[0040] (3) vacuum degassing the mixture B to obtain a casting slurry, and then performing casting molding to obtain a casting green sheet;

[0041] (4) Sintering the tape-cast green sheet obtained in step (3) in an inert atmosphere at a heating rate of 25°C / min to a temperature of 1900°C and maintaining the temperature for 8 hours.

[0042] Comparative Example 1

[0043] Weigh the specific raw materials according to Table 1, and the remaining preparation steps are as follows:

[0044] (1) Silicon nitride, boron nitride whiskers, potassium hexatitanate whiskers, yttrium oxide, and lanthanum oxide were stirred uniformly, and then isopropyl alcohol, triolein, ethyl acetate, and anhydrous ethanol were added, stirred uniformly, and ball-milled for 20 hours to obtain a mixture A;

[0045] (2) Add dibutyl phthalate and polyvinyl butyral to mixture A, stir evenly, and then ball-mill for 12 hours to obtain mixture B;

[0046] (3) vacuum degassing the mixture B to obtain a casting slurry, and then performing casting molding to obtain a casting green sheet;

[0047] (4) Sintering the tape-cast green sheet obtained in step (3) in an inert atmosphere at a heating rate of 25°C / min to a temperature of 1900°C and maintaining the temperature for 8 hours.

[0048] Comparative Example 2

[0049] Weigh the specific raw materials according to Table 1, and the remaining preparation steps are as follows:

[0050] (1) Silicon nitride, boron nitride whiskers, potassium hexatitanate whiskers, titanium carbonitride, yttrium oxide, and lanthanum oxide were mixed uniformly, and then isopropyl alcohol, triolein, ethyl acetate, and anhydrous ethanol were added. After mixing uniformly, the mixture was ball-milled and dispersed for 20 hours to obtain a mixture A.

[0051] (2) Add dibutyl phthalate and polyvinyl butyral to mixture A, stir evenly, and then ball-mill for 12 hours to obtain mixture B;

[0052] (3) vacuum degassing the mixture B to obtain a casting slurry, and then performing casting molding to obtain a casting green sheet;

[0053] (4) Sintering the tape-cast green sheet obtained in step (3) in an inert atmosphere at a heating rate of 25°C / min to a temperature of 1900°C and maintaining the temperature for 8 hours.

[0054] Comparative Example 3

[0055] Weigh the specific raw materials according to Table 1, and the remaining preparation steps are as follows:

[0056] (1) Silicon nitride, boron nitride whiskers, potassium hexatitanate whiskers, zirconium tungstate, yttrium oxide, and lanthanum oxide were mixed uniformly, and then isopropyl alcohol, triolein, ethyl acetate, and anhydrous ethanol were added, mixed uniformly, and ball-milled for 20 hours to obtain a mixture A;

[0057] (2) Add dibutyl phthalate and polyvinyl butyral to mixture A, stir evenly, and then ball-mill for 12 hours to obtain mixture B;

[0058] (3) vacuum degassing the mixture B to obtain a casting slurry, and then performing casting molding to obtain a casting green sheet;

[0059] (4) Sintering the tape-cast green sheet obtained in step (3) in an inert atmosphere at a heating rate of 25°C / min to a temperature of 1900°C and maintaining the temperature for 8 hours.

[0060] Comparative Example 4

[0061] Weigh the specific raw materials according to Table 1, and the remaining preparation steps are as follows:

[0062] (1) Silicon nitride, boron nitride whiskers, potassium hexatitanate whiskers, titanium dioxide, zirconium tungstate, yttrium oxide, and lanthanum oxide were mixed uniformly, and then isopropyl alcohol, triolein, ethyl acetate, and anhydrous ethanol were added. After mixing uniformly, the mixture was ball-milled and dispersed for 20 hours to obtain a mixture A;

[0063] (2) Add dibutyl phthalate and polyvinyl butyral to mixture A, stir evenly, and then ball-mill for 12 hours to obtain mixture B;

[0064] (3) vacuum degassing the mixture B to obtain a casting slurry, and then performing casting molding to obtain a casting green sheet;

[0065] (4) Sintering the tape-cast green sheet obtained in step (3) in an inert atmosphere at a heating rate of 25°C / min to a temperature of 1900°C and maintaining the temperature for 8 hours.

[0066] Table 1

[0067]

[0068] Example 4 Performance Test

[0069] The thermal conductivity, flexural strength, and fracture toughness of the composite ceramic substrates prepared in Examples 1-3 and Comparative Examples 1-4 were tested. A 12μm thick metal film was deposited on the composite ceramic substrates prepared in Examples 1-3 and Comparative Examples 1-4 by sputtering using titanium, nickel, and aluminum as the metal raw materials, and the bonding strength was measured. The test results are shown in Table 2.

[0070] Table 2 Performance test results

[0071]

[0072] The foregoing descriptions of specific exemplary embodiments of the present invention are for purposes of illustration and description. These descriptions are not intended to limit the invention to the precise forms disclosed, and it is apparent that many modifications and variations are possible in light of the foregoing teachings. The exemplary embodiments have been selected and described for the purpose of explaining the specific principles of the invention and their practical application, thereby enabling those skilled in the art to make and utilize a variety of exemplary embodiments of the invention and various options and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A silicon nitride-based composite ceramic substrate, characterized in that: The silicon nitride-based composite ceramic substrate is composed of the following raw materials: 95-110 parts of silicon nitride, 4-8 parts of boron nitride whiskers, 7-14 parts of potassium hexatitanate whiskers, 2-7 parts of titanium carbonitride, 6-12 parts of zirconium tungstate, 10-18 parts of yttrium oxide, 12-20 parts of lanthanum oxide, 14-20 parts of dibutyl phthalate, 6-15 parts of triolein, 16-25 parts of polyvinyl butyral, 50-65 parts of isopropyl alcohol, 25-30 parts of ethyl acetate, and 10-20 parts of anhydrous ethanol.

2. The silicon nitride-based composite ceramic substrate according to claim 1, characterized in that: The silicon nitride is β-silicon nitride with an average particle size of 1 μm and a specific surface area of ​​49 m 2 / g, the crystal phase is β phase; the average particle size of the titanium carbonitride is 3um, and the specific surface area is 21 m 2 / g; the average particle size of the zirconium tungstate is 3um.

3. The silicon nitride-based composite ceramic substrate according to claim 1, characterized in that: The silicon nitride-based composite ceramic substrate is composed of the following raw materials: 100 parts of silicon nitride, 6 parts of boron nitride whiskers, 10 parts of potassium hexatitanate whiskers, 4 parts of titanium carbonitride, 9 parts of zirconium tungstate, 13 parts of yttrium oxide, 16 parts of lanthanum oxide, 18 parts of dibutyl phthalate, 8 parts of triolein, 22 parts of polyvinyl butyral, 60 parts of isopropyl alcohol, 30 parts of ethyl acetate, and 15 parts of anhydrous ethanol.

4. A method for preparing the silicon nitride-based composite ceramic substrate according to any one of claims 1 to 3, characterized in that: The method comprises the following steps: (1) Silicon nitride, boron nitride whiskers, potassium hexatitanate whiskers, titanium carbonitride, zirconium tungstate, yttrium oxide, and lanthanum oxide were mixed evenly, and then isopropyl alcohol, triolein, ethyl acetate, and anhydrous ethanol were added. After mixing evenly, the mixture was ball-milled and dispersed for 18 to 20 hours to obtain a mixture A. (2) Add dibutyl phthalate and polyvinyl butyral to mixture A, stir evenly, and then ball-mill for 10-12 hours to obtain mixture B; (3) vacuum degassing the mixture B to obtain a casting slurry, and then performing casting molding to obtain a casting green sheet; (4) Sintering the tape-cast green sheet obtained in step (3) in an inert atmosphere at a heating rate of 20 to 25°C / min to a temperature of 1850 to 1900°C and maintaining the temperature for 6 to 8 hours.

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