Nickel-coated multilayer ceramic substrate and method of manufacturing the same

Abstract

The application relates to the technical field of ceramic substrates, and discloses a nickel-coated multilayer ceramic substrate and a preparation method thereof. The nickel-coated multilayer ceramic substrate comprises an alumina ceramic substrate and a nickel-coated layer arranged on at least one side of the alumina ceramic substrate; the alumina ceramic substrate comprises the following raw materials in parts by weight: 70-90 parts of alumina, 5-8 parts of a sintering aid, 80-100 parts of a solvent, 10-12 parts of a binder and 0.5-2 parts of a dispersing agent; and the sintering aid comprises corundum-mullite composite material and zirconia-silicon carbide composite material. The above technical scheme solves the problem of insufficient strength of the nickel-coated multilayer ceramic substrate in the related art.

Description

Technical Field

[0001] This invention relates to the field of ceramic substrate technology, and more specifically, to a nickel-coated multilayer ceramic substrate and its preparation method. Background Technology

[0002] In the rapid development of the modern electronic information industry, electronic devices are constantly evolving towards higher integration, higher power density, and miniaturization, which places more stringent demands on the performance of electronic packaging substrates. Among them, nickel-clad multilayer ceramic substrates have excellent high-temperature resistance, thermal conductivity, and good insulation properties, and are widely used in high-end electronic fields such as power electronic modules, radio frequency microwave devices, and optoelectronic components, becoming a key basic component to ensure the stable and efficient operation of electronic devices.

[0003] However, in practical applications, although nickel-plated multilayer ceramic substrates possess excellent high-temperature resistance and insulation properties, they still suffer from insufficient strength. When subjected to external impacts, vibrations, or thermal stress, they are prone to internal defects such as cracks, leading to a decrease in the overall strength of the substrate. While the nickel plating layer typically uses pure nickel or nickel alloys, which have good ductility and conductivity, the bonding strength between it and the ceramic substrate is affected by various factors. If defects exist at the bonding interface (such as pores, oxide layers, impurities, etc.), the nickel layer is prone to peeling off from the ceramic substrate when subjected to external forces or thermal cycling, further exacerbating the substrate's insufficient strength.

[0004] Therefore, there is a need to develop a high-strength nickel-coated multilayer ceramic substrate to broaden its application in the field of electronic packaging. Summary of the Invention

[0005] This invention proposes a nickel-coated multilayer ceramic substrate and its preparation method, which solves the problem of insufficient strength of nickel-coated multilayer ceramic substrates in related technologies.

[0006] The technical solution of the present invention is as follows:

[0007] This invention proposes a nickel-coated multilayer ceramic substrate, comprising an alumina ceramic substrate and a nickel-coated layer disposed on at least one side of the alumina ceramic substrate;

[0008] The alumina ceramic substrate comprises the following raw materials in parts by weight: 70-90 parts alumina, 5-8 parts sintering aid, 80-100 parts solvent, 10-12 parts binder, and 0.5-2 parts dispersant;

[0009] The sintering aids include corundum-mullite composite materials and zirconium oxide-silicon carbide composite materials.

[0010] As a further technical solution, the mass ratio of the corundum-mullite composite material and the zirconium oxide-silicon carbide composite material is 1:4 to 4:1.

[0011] As a further technical solution, the raw materials of the corundum-mullite composite material include kaolin and diatomite in a mass ratio of 1~2:3; the mass ratio of kaolin and diatomite can be, for example, 1:3, 1.2:3, 1.4:3, 1.6:3, 1.8:3, or 2:3.

[0012] As a further technical solution, the raw materials of the zirconium oxide-silicon carbide composite material include zirconium oxide and silicon carbide in a mass ratio of 4:0.2 to 0.8; the mass ratio of zirconium oxide to silicon carbide can be, for example, 4:0.2, 4:0.4, 4:0.6, 4:0.7, or 4:0.8.

[0013] As a further technical solution, the raw materials of the zirconium oxide-silicon carbide composite material also include a sintering aid, the sintering aid including alumina, and the mass ratio of the sintering aid to zirconium oxide is 0.1~0.3:4.

[0014] As a further technical solution, the preparation method of the corundum-mullite composite material includes the following steps: ball milling and mixing the raw materials of the corundum-mullite composite material, hot pressing and sintering, and pulverizing to obtain the corundum-mullite composite material.

[0015] As a further technical solution, the preparation method of the zirconia-silicon carbide composite material includes the following steps: ball milling and mixing the raw materials of the zirconia-silicon carbide composite material, hot pressing and sintering, and pulverizing to obtain the zirconia-silicon carbide composite material.

[0016] As a further technical solution, the dispersant includes polyacrylate.

[0017] In the nickel-coated multilayer ceramic substrate of the present invention, the dispersant includes polyacrylate. The dispersing properties of polyacrylate enable the raw materials to be uniformly dispersed during processing, reducing agglomeration, which is beneficial to subsequent molding and processing and improves production efficiency. Polyacrylate can be, for example, sodium polyacrylate, potassium polyacrylate, etc.

[0018] As a further technical solution, the adhesive includes a water-soluble polymer.

[0019] In the nickel-coated multilayer ceramic substrate of the present invention, the binder includes a water-soluble polymer. The water-soluble polymer has good water solubility and good bonding properties, which can quickly achieve the bonding of materials during the ceramic substrate processing. The water-soluble polymer can be, for example, polyethylene glycol, polyvinyl alcohol, polyacrylamide, sodium carboxymethyl cellulose, etc.

[0020] This invention also proposes a method for preparing a nickel-coated multilayer ceramic substrate, comprising the following steps:

[0021] S1. Mix alumina, sintering aid, dispersant and solvent to obtain a mixture;

[0022] S2. Add a binder to the mixture and mix, then cast and dry to obtain a raw ceramic sheet;

[0023] S3. After drilling holes in the raw ceramic sheet, the surface is printed, laminated, connected to the top and bottom, cut, sintered, and cooled to obtain an alumina ceramic substrate.

[0024] S4. After ultrasonic cleaning of the alumina ceramic substrate, the alumina ceramic substrate is placed in a chemical nickel plating solution for chemical nickel plating and then dried to obtain the nickel-coated multilayer ceramic substrate.

[0025] As a further technical solution, the sintering temperature is 1600~1700℃.

[0026] As a further technical solution, each 1L of the electroless nickel plating solution includes the following components: 20-25g nickel sulfate, 20-25g sodium hypophosphite, 25-35g sodium citrate, 0.001-0.004g sodium dodecyl sulfonate, 3-6g sodium acetate, and 5-10g boric acid.

[0027] As a further technical solution, the preparation method of the electroless nickel plating solution includes the following steps: adding nickel sulfate, sodium hypophosphite, sodium citrate, sodium dodecyl sulfonate, sodium acetate and boric acid to water and mixing them to obtain an electroless nickel plating solution.

[0028] As a further technical solution, the pH value during the electroless nickel plating process is controlled at 4-5, the temperature at 80-90℃, and the time at 8-10 minutes.

[0029] The working principle and beneficial effects of this invention are as follows:

[0030] In this invention, corundum-mullite composite material and zirconia-silicon carbide composite material are used as sintering aids to improve the strength of nickel-coated multilayer ceramic substrates. In practical applications, nickel-coated multilayer ceramic substrates are commonly used in electronic devices and other fields, and need to withstand certain mechanical and thermal stresses. The sintering aid system of this invention, with its corundum-mullite composite material optimizing crystal phase composition and promoting crystal growth, stabilizes the internal structure of the ceramic substrate, enhancing its hardness and toughness. The zirconia-silicon carbide composite material, through phase transformation toughening and dispersion strengthening, effectively prevents crack propagation, improving the material's strength and resistance to deformation. The synergistic effect of these two materials allows the nickel-coated multilayer ceramic substrate to more effectively disperse stress, resist deformation and fracture, and improve its strength when facing external forces. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1

[0033] A nickel-coated multilayer ceramic substrate includes an alumina ceramic substrate and a nickel-coated layer;

[0034] The alumina ceramic substrate comprises the following raw materials in parts by weight: 70 parts alumina (20μm), 5 parts sintering aid, 80 parts water, 10 parts polyethylene glycol, and 0.5 parts sodium polyacrylate.

[0035] The sintering aids are corundum-mullite composite material and zirconium oxide-silicon carbide composite material with a mass ratio of 5:1.

[0036] The raw materials for corundum-mullite composite materials include kaolin and diaspore in a mass ratio of 1:3.

[0037] The raw materials for the zirconium oxide-silicon carbide composite material include zirconium oxide and silicon carbide in a mass ratio of 4:0.2;

[0038] The preparation method of corundum-mullite composite material includes the following steps: the raw materials of corundum-mullite composite material are ball-milled and mixed at 600 rpm for 10 min, hot-pressed and sintered at 1550℃ for 3 h, and pulverized to obtain corundum-mullite composite material with a particle size of 5 μm.

[0039] The preparation method of zirconia-silicon carbide composite material includes the following steps: zirconia, silicon carbide and sintering aid (alumina) are ball-milled at 800 rpm for 10 min, hot-pressed and sintered at 1500℃ under argon atmosphere for 4 h, and then pulverized to obtain zirconia-silicon carbide composite material with a particle size of 5 μm. The mass ratio of sintering aid to zirconia is 0.1:4.

[0040] A method for preparing a nickel-coated multilayer ceramic substrate includes the following steps:

[0041] S1. Mix alumina, sintering aid, sodium polyacrylate and water to obtain a mixture;

[0042] S2. Add polyethylene glycol to the mixture and mix, then cast and dry to obtain raw ceramic sheets;

[0043] S3. After drilling holes in the raw ceramic sheet, surface printing, stacking 30 layers, top and bottom conduction, cutting, sintering at 1600℃ for 3 hours, and cooling are performed to obtain an alumina ceramic substrate.

[0044] S4. Grind the upper surface of the alumina ceramic substrate to a roughness of 0.25 μm, then ultrasonically clean it in acetone, dry it, acidify it in a 37% hydrochloric acid solution for 20 seconds, rinse it with deionized water, place it in an activation solution (each 1L of activation solution includes 3g of palladium chloride and 180mL of 37% hydrochloric acid), activate it at 35℃ for 3 minutes, rinse it with deionized water, place the alumina ceramic substrate in a chemical nickel plating solution (pH value 5), perform chemical nickel plating at 85℃ for 9 minutes, rinse it, dry it, and obtain a nickel-coated multilayer ceramic substrate. Each 1L of chemical nickel plating solution (solvent is water) includes the following components: 23g of nickel sulfate, 24g of sodium hypophosphite, 30g of sodium citrate, 0.002g of sodium dodecyl sulfonate, 5g of sodium acetate, and 8g of boric acid.

[0045] The preparation method of electroless nickel plating solution includes the following steps: adding nickel sulfate, sodium hypophosphite, sodium citrate, sodium dodecyl sulfonate, sodium acetate and boric acid to water and mixing them to obtain electroless nickel plating solution.

[0046] Example 2

[0047] A nickel-coated multilayer ceramic substrate includes an alumina ceramic substrate and a nickel-coated layer;

[0048] The alumina ceramic substrate comprises the following raw materials in parts by weight: 90 parts alumina (20μm), 8 parts sintering aid, 100 parts water, 12 parts polyethylene glycol, and 2 parts sodium polyacrylate.

[0049] The sintering aids are corundum-mullite composite material and zirconium oxide-silicon carbide composite material with a mass ratio of 5:1.

[0050] The raw materials for corundum-mullite composite materials include kaolin and diaspore in a mass ratio of 2:3.

[0051] The raw materials for the zirconium oxide-silicon carbide composite material include zirconium oxide and silicon carbide in a mass ratio of 4:0.6;

[0052] The preparation method of corundum-mullite composite material includes the following steps: the raw materials of corundum-mullite composite material are ball-milled and mixed at 600 rpm for 10 min, hot-pressed and sintered at 1550℃ under argon atmosphere for 3 h, and then pulverized to obtain corundum-mullite composite material with a particle size of 5 μm.

[0053] The preparation method of zirconia-silicon carbide composite material includes the following steps: zirconia, silicon carbide and sintering aid (alumina) are ball-milled at 800 rpm for 10 min, hot-pressed and sintered at 1500℃ for 4 h, and then pulverized to obtain zirconia-silicon carbide composite material with a particle size of 5 μm. The mass ratio of sintering aid to zirconia is 0.3:4.

[0054] A method for preparing a nickel-coated multilayer ceramic substrate includes the following steps:

[0055] S1. Mix alumina, sintering aid, sodium polyacrylate and water to obtain a mixture;

[0056] S2. Add polyethylene glycol to the mixture and mix, then cast and dry to obtain raw ceramic sheets;

[0057] S3. After drilling holes in the raw ceramic sheet, surface printing, stacking 30 layers, top and bottom conduction, cutting, sintering at 1700℃ for 2 hours, and cooling are performed to obtain an alumina ceramic substrate.

[0058] S4. Grind the upper surface of the alumina ceramic substrate to a roughness of 0.25 μm, then ultrasonically clean it in acetone, dry it, acidify it in a 37% hydrochloric acid solution for 20 seconds, rinse it with deionized water, place it in an activation solution (each 1L of activation solution includes 3g of palladium chloride and 180mL of 37% hydrochloric acid), activate it at 35℃ for 3 minutes, rinse it with deionized water, place the alumina ceramic substrate in a chemical nickel plating solution (pH value 5), perform chemical nickel plating at 85℃ for 9 minutes, rinse it, dry it, and obtain a nickel-coated multilayer ceramic substrate. Each 1L of chemical nickel plating solution (solvent is water) includes the following components: 23g of nickel sulfate, 24g of sodium hypophosphite, 30g of sodium citrate, 0.002g of sodium dodecyl sulfonate, 5g of sodium acetate, and 8g of boric acid.

[0059] The preparation method of electroless nickel plating solution includes the following steps: adding nickel sulfate, sodium hypophosphite, sodium citrate, sodium dodecyl sulfonate, sodium acetate and boric acid to water and mixing them to obtain electroless nickel plating solution.

[0060] Example 3

[0061] A nickel-coated multilayer ceramic substrate includes an alumina ceramic substrate, an interface bonding layer, and a nickel-coated layer.

[0062] The alumina ceramic substrate comprises the following raw materials in parts by weight: 80 parts alumina (20μm), 7 parts sintering aid, 90 parts water, 11 parts polyethylene glycol, and 1.5 parts sodium polyacrylate.

[0063] The sintering aids are corundum-mullite composite material and zirconium oxide-silicon carbide composite material with a mass ratio of 5:1.

[0064] The raw materials for corundum-mullite composite materials include kaolin and diaspore in a mass ratio of 1:3.

[0065] The raw materials for the zirconium oxide-silicon carbide composite material include zirconium oxide and silicon carbide in a mass ratio of 4:0.8;

[0066] The preparation method of corundum-mullite composite material includes the following steps: the raw materials of corundum-mullite composite material are ball-milled and mixed at 600 rpm for 10 min, hot-pressed and sintered at 1550℃ for 3 h, and pulverized to obtain corundum-mullite composite material with a particle size of 5 μm.

[0067] The preparation method of zirconia-silicon carbide composite material includes the following steps: zirconia, silicon carbide and sintering aid (alumina) are ball-milled at 800 rpm for 10 min, hot-pressed and sintered at 1500℃ under argon atmosphere for 4 h, and then pulverized to obtain zirconia-silicon carbide composite material with a particle size of 5 μm. The mass ratio of sintering aid to zirconia is 0.3:4.

[0068] A method for preparing a nickel-coated multilayer ceramic substrate includes the following steps:

[0069] S1. Mix alumina, sintering aid, sodium polyacrylate and water to obtain a mixture;

[0070] S2. Add polyethylene glycol to the mixture and mix, then cast and dry to obtain raw ceramic sheets;

[0071] S3. After drilling holes in the raw ceramic sheet, surface printing, stacking 30 layers, top and bottom conduction, cutting, sintering at 1650℃ for 2.5h, and cooling are performed to obtain an alumina ceramic substrate.

[0072] S4. Grind the upper surface of the alumina ceramic substrate to a roughness of 0.25 μm, then ultrasonically clean it in acetone, dry it, acidify it in a 37% hydrochloric acid solution for 20 seconds, rinse it with deionized water, place it in an activation solution (each 1L of activation solution includes 3g of palladium chloride and 180mL of 37% hydrochloric acid), activate it at 35℃ for 3 minutes, rinse it with deionized water, place the alumina ceramic substrate in a chemical nickel plating solution (pH value 5), perform chemical nickel plating at 85℃ for 9 minutes, rinse it, dry it, and obtain a nickel-coated multilayer ceramic substrate. Each 1L of chemical nickel plating solution (solvent is water) includes the following components: 23g of nickel sulfate, 24g of sodium hypophosphite, 30g of sodium citrate, 0.002g of sodium dodecyl sulfonate, 5g of sodium acetate, and 8g of boric acid.

[0073] The preparation method of electroless nickel plating solution includes the following steps: adding nickel sulfate, sodium hypophosphite, sodium citrate, sodium dodecyl sulfonate, sodium acetate and boric acid to water and mixing them to obtain electroless nickel plating solution.

[0074] Example 4

[0075] The only difference between this embodiment and Embodiment 3 is that the sintering aids are corundum-mullite composite material and zirconium oxide-silicon carbide composite material with a mass ratio of 1:5.

[0076] Example 5

[0077] The only difference between this embodiment and Embodiment 3 is that the sintering aids are corundum-mullite composite material and zirconium oxide-silicon carbide composite material with a mass ratio of 1:4.

[0078] Example 6

[0079] The only difference between this embodiment and Embodiment 3 is that the sintering aids are corundum-mullite composite material and zirconia-silicon carbide composite material with a mass ratio of 4:1.

[0080] Comparative Example 1

[0081] The only difference between this comparative example and Example 3 is that the corundum-mullite composite material is replaced with a zirconium oxide-silicon carbide composite material.

[0082] Comparative Example 2

[0083] The only difference between this comparative example and Example 3 is that the zirconia-silicon carbide composite material is replaced with a corundum-mullite composite material.

[0084] The bending strength and tensile bond strength of the nickel-coated multilayer ceramic substrates prepared in Examples 1-6 and Comparative Examples 1-2 were tested respectively:

[0085] Bending strength: The test method is as specified in standard GB / T 6569-2006 "Test Method for Bending Strength of Fine Ceramics", and the test method adopts three-point bending.

[0086] Coating tensile bond strength: The tensile bond strength of the coating was tested according to the test method specified in standard GB / T 39685-2020 "Test Method for Bond Strength of Ceramic Coatings".

[0087] The results are shown in Table 1 below.

[0088] Table 1 Performance Test Results

[0089]

[0090] Compared with the comparative example, the embodiments of the present invention use corundum-mullite composite material and zirconia-silicon carbide composite material as sintering aids to improve the strength of nickel-coated multilayer ceramic substrates. At the same time, the nickel-coated multilayer ceramic substrates prepared in the embodiments of the present invention have higher tensile bonding strength of the coating and excellent bonding interface between the nickel coating and the alumina ceramic substrate.

[0091] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A nickel-coated multilayer ceramic substrate, characterized in that, It includes an alumina ceramic substrate and a nickel plating layer disposed on at least one side of the alumina ceramic substrate; The alumina ceramic substrate comprises the following raw materials in parts by weight: 70-90 parts alumina, 5-8 parts sintering aid, 80-100 parts solvent, 10-12 parts binder, and 0.5-2 parts dispersant; the sintering aid includes corundum-mullite composite material and zirconium oxide-silicon carbide composite material. The mass ratio of the corundum-mullite composite material and the zirconium oxide-silicon carbide composite material is 1:4 to 4:1; The raw materials for the corundum-mullite composite material include kaolin and diaspore in a mass ratio of 1~2:3; The raw materials of the zirconium oxide-silicon carbide composite material include zirconium oxide and silicon carbide in a mass ratio of 4:0.2~0.

8.

2. The nickel-coated multilayer ceramic substrate according to claim 1, characterized in that, The preparation method of the corundum-mullite composite material includes the following steps: ball milling and mixing the raw materials of the corundum-mullite composite material, hot pressing and sintering, and pulverizing to obtain the corundum-mullite composite material.

3. The nickel-coated multilayer ceramic substrate according to claim 1, characterized in that, The preparation method of the zirconia-silicon carbide composite material includes the following steps: ball milling and mixing the raw materials of the zirconia-silicon carbide composite material, hot pressing and sintering, and pulverizing to obtain the zirconia-silicon carbide composite material.

4. The nickel-coated multilayer ceramic substrate according to claim 1, characterized in that, The dispersant includes polyacrylate.

5. The nickel-coated multilayer ceramic substrate according to claim 1, characterized in that, The adhesive comprises a water-soluble polymer.

6. A method for preparing a nickel-coated multilayer ceramic substrate, used to prepare the nickel-coated multilayer ceramic substrate according to any one of claims 1 to 5, characterized in that, Includes the following steps: S1. Mix alumina, sintering aid, dispersant and solvent to obtain a mixture; S2. Add a binder to the mixture and mix, then cast and dry to obtain a raw ceramic sheet; S3. After drilling holes in the raw ceramic sheet, the surface is printed, laminated, connected to the top and bottom, cut, sintered, and cooled to obtain an alumina ceramic substrate. S4. After ultrasonic cleaning of the alumina ceramic substrate, the alumina ceramic substrate is placed in a chemical nickel plating solution for chemical nickel plating and then dried to obtain the nickel-coated multilayer ceramic substrate.

7. The method for preparing a nickel-coated multilayer ceramic substrate according to claim 6, characterized in that, Each 1L of the electroless nickel plating solution comprises the following components: 20-25g nickel sulfate, 20-25g sodium hypophosphite, 25-35g sodium citrate, 0.001-0.004g sodium dodecyl sulfonate, 3-6g sodium acetate, and 5-10g boric acid; The sintering temperature is 1600~1700℃.

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