Corrosion-resistant multilayer ceramic substrate and preparation method thereof

Abstract

The invention relates to the technical field of ceramic substrates, and provides a corrosion-resistant multilayer ceramic substrate and a preparation method thereof. The corrosion-resistant multilayer ceramic substrate comprises the following raw material components in parts by weight: 90-100 parts of aluminum nitride, 4-8 parts of a plasticizer, 5-10 parts of a sintering aid, 3-7 parts of a binder, 2-5 parts of a dispersant, 5-12 parts of a reinforcing agent and 60-70 parts of a solvent, the reinforcing agent comprises metal powder and yttrium hydride; the metal powder comprises nickel powder and titanium powder. According to the technical scheme, the problem of poor bending strength of the ceramic substrate in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramic substrates, and in particular to a corrosion-resistant multilayer ceramic substrate and a preparation method thereof. Background Art

[0002] At a time when the electronic information industry is developing rapidly, ceramic substrates, as key electronic materials, play a vital role in the fields of electronic packaging, integrated circuits, etc. Among them, aluminum nitride ceramic substrates have become an ideal choice for many high-end electronic devices due to their advantages such as high thermal conductivity, good electrical insulation and thermal expansion coefficient.

[0003] However, in actual application scenarios, aluminum nitride ceramic substrates face severe challenges. As electronic devices develop towards miniaturization and high performance, the requirements for the mechanical properties of ceramic substrates, especially bending strength, are becoming more and more stringent. Miniaturization means that the layout of electronic components is more compact, and ceramic substrates need to carry more electronic components in a limited space, which makes the stress distribution of the substrate more complex and concentrated when subjected to external forces. For example, in products such as smartphones and wearable devices, in pursuit of lightness and portability, the thickness of ceramic substrates continues to decrease, but the bending stress they bear has not decreased accordingly, but has increased due to the increased compactness of the internal structure of the device. Under the trend of high performance, the high heat generated by electronic equipment during operation needs to be discharged through an efficient heat dissipation system, which requires ceramic substrates to withstand not only mechanical stress, but also thermal stress caused by differences in thermal expansion coefficients. When thermal stress and mechanical stress are superimposed, if the bending strength of the ceramic substrate is insufficient, it is very easy to break under the action of these stresses.

[0004] In the chemical industry, corrosion-resistant ceramic substrates are often used to make key components such as reactor linings and pipelines to resist erosion by various highly corrosive chemicals. However, under the complex working conditions of chemical production, these components must not only withstand the continuous scouring of fluids and the interference of mechanical vibrations, but also deal with thermal stress caused by temperature changes. Due to the low bending strength of existing corrosion-resistant ceramic substrates, they are prone to deformation and rupture under the combined effect of multiple factors, which can lead to serious safety accidents such as leakage. This will not only lead to production interruptions and reduce production efficiency, but may also pollute the environment and pose a huge threat to personnel safety.

[0005] To meet these growing demands, it is urgent to develop a corrosion-resistant aluminum nitride multilayer ceramic substrate technology that can significantly improve the bending strength. Summary of the invention

[0006] The present invention provides a corrosion-resistant multilayer ceramic substrate and a preparation method thereof, which solves the problem of poor bending strength of the ceramic substrate in the related art.

[0007] The technical solution of the present invention is as follows: The present invention provides a corrosion-resistant multilayer ceramic substrate, wherein the raw materials include the following components in parts by weight: 90-100 parts of aluminum nitride, 4-8 parts of a plasticizer, 5-10 parts of a sintering aid, 3-7 parts of a binder, 2-5 parts of a dispersant, 5-12 parts of a reinforcing agent, and 60-70 parts of a solvent; The reinforcing agent includes metal powder and yttrium hydride; The metal powder includes nickel powder and titanium powder.

[0008] As a further technical solution, the mass ratio of the nickel powder, titanium powder and yttrium hydride is 5:2:3~5.

[0009] In the present invention, the bending strength of the ceramic substrate is further improved by adjusting the mass ratio of nickel powder, titanium powder and yttrium hydride to 5:2:3-5.

[0010] As a further technical solution, the metal powder is sintered metal powder.

[0011] As a further technical solution, the method for preparing the sintered metal powder comprises the following steps: A1, ball-milling nickel powder and titanium powder to obtain a mixture; A2. The mixed material is subjected to spark plasma sintering to obtain sintered metal powder.

[0012] As a further technical solution, the ball milling includes a first stage of ball milling and a second stage of ball milling; During the first stage of ball milling, the rotation speed is 100-200 rpm and the time is 2-5 hours; During the second stage of ball milling, the rotation speed is 600-800 rpm and the time is 1-4 hours.

[0013] As a further technical solution, the spark plasma sintering is carried out in an inert gas atmosphere; The inert gas is one of argon and helium.

[0014] As a further technical solution, during the spark plasma sintering, the temperature is 1000-1200° C., the pressure is 30-60 MPa, and the time is 15-20 min.

[0015] In the present invention, when the metal powder used is sintered metal powder, a strong metal bond connection is formed between the metal powders, which improves the density of the metal powders, thereby improving the density of the ceramic substrate, preventing corrosive substances from corroding through the pores, and improving the corrosion resistance of the ceramic substrate.

[0016] As a further technical solution, the plasticizer includes one of dibutyl phthalate and dioctyl phthalate; The sintering aid includes one of calcium oxide and magnesium oxide; The binder includes one of polyvinyl butyral and polymethyl methacrylate; The dispersant includes one of sodium polyacrylate and dibutyl phosphate; The solvent includes one of n-butanol, isopropanol and ethanol.

[0017] In the present invention, when a plasticizer is added to the raw material, the friction between the raw material particles is reduced, the plasticity and flexibility of the raw material are increased, and it is easier to process it into a specific shape during the molding process; In the present invention, when a sintering aid is added to the raw material, the sintering aid promotes the sintering process of aluminum nitride, reduces the sintering temperature, reduces energy consumption, and avoids problems such as excessive grain growth that may occur at high temperatures, which is conducive to obtaining a ceramic substrate with good performance; In the present invention, when a binder is added to the raw material, the binder forms a bonding bridge between the raw material powder particles, firmly bonding the particles together, so that the green body has a certain shape and strength; In the present invention, when a dispersant is added to the raw material, the dispersant can be attached to the surface of the raw material particles, so that electrostatic repulsion or steric hindrance effect is generated between the particles, effectively preventing the particles from agglomerating, ensuring that the particles are evenly dispersed in the solvent, and improving the mixing uniformity of the raw materials.

[0018] The present invention also proposes a method for preparing the corrosion-resistant multilayer ceramic substrate, comprising the following steps: S1. Evenly mix aluminum nitride, plasticizer, sintering aid, dispersant, reinforcing agent and solvent, and then add binder to obtain slurry; S2, tape-casting the slurry, and drying it to obtain a blank; S3, punching holes in the blank, and performing surface printing, lamination, upper and lower conduction, cutting, sintering, and cooling to obtain a corrosion-resistant multilayer ceramic substrate.

[0019] As a further technical solution, the raw material for surface printing is tungsten paste; During the sintering, the temperature is 1650-1740°C.

[0020] The working principle and beneficial effects of the present invention are: In the present invention, nickel powder, titanium powder and yttrium hydride are added as reinforcing agents. Nickel powder and titanium powder are ductile metals. Yttrium hydride promotes dense sintering during the sintering process. Nickel powder, titanium powder and yttrium hydride work synergistically to improve the bending strength of the ceramic substrate, thereby significantly improving the reliability and service life of the ceramic substrate in electronic product applications, and also enabling the ceramic substrate to be used in more scenarios with stringent requirements on material properties. DETAILED DESCRIPTION

[0021] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In the following examples and comparative examples, the nickel powder content is 99.9wt%, the particle size is 300 mesh, the titanium powder content is 99.9wt%, the particle size is 325 mesh, the yttrium hydride content is 99.9wt%, the particle size is 200 mesh, the polyvinyl butyral weight average molecular weight is 30000, the polymethyl methacrylate model is VH-001, and the sodium polyacrylate weight average molecular weight is 10000.

[0023] Example 1 A corrosion-resistant multilayer ceramic substrate, the raw materials include the following components in parts by weight: 100 parts of aluminum nitride, 8 parts of plasticizer, 10 parts of sintering aid, 7 parts of binder, 5 parts of dispersant, 12 parts of reinforcing agent, and 70 parts of solvent; The reinforcing agent includes nickel powder, titanium powder and yttrium hydride in a mass ratio of 5:2:7; The plasticizer is dibutyl phthalate; The sintering aid is calcium oxide; The binder is polyvinyl butyral; The dispersant is sodium polyacrylate; The solvent is n-butanol; A method for preparing a corrosion-resistant multilayer ceramic substrate comprises the following steps: S1. Mix aluminum nitride, plasticizer, sintering aid, dispersant, reinforcing agent and solvent evenly, then add binder and continue mixing until evenly mixed to obtain slurry; S2, tape-casting the slurry, drying it, and obtaining a blank; S3, punching holes in the blank, surface printing, lamination, upper and lower conduction, cutting, sintering at 1740° C., and cooling to obtain a corrosion-resistant multilayer ceramic substrate; The raw material for surface printing is tungsten paste, and the printing thickness is 20μm; The number of layers of the multilayer ceramic substrate is 30.

[0024] Example 2 A corrosion-resistant multilayer ceramic substrate, the raw materials include the following components in parts by weight: 90 parts of aluminum nitride, 4 parts of plasticizer, 5 parts of sintering aid, 3 parts of binder, 2 parts of dispersant, 5 parts of reinforcing agent, and 60 parts of solvent; The reinforcing agent includes nickel powder, titanium powder and yttrium hydride in a mass ratio of 5:2:1; The plasticizer is dioctyl phthalate; The sintering aid is magnesium oxide; The binder is polymethyl methacrylate; The dispersant is dibutyl phosphate; The solvent is isopropanol; A method for preparing a corrosion-resistant multilayer ceramic substrate comprises the following steps: S1. Mix aluminum nitride, plasticizer, sintering aid, dispersant, reinforcing agent and solvent evenly, then add binder and continue mixing until evenly mixed to obtain slurry; S2, tape-casting the slurry, drying it, and obtaining a blank; S3, punching holes in the blank, surface printing, lamination, upper and lower conduction, cutting, sintering at 1650° C., and cooling to obtain a corrosion-resistant multilayer ceramic substrate; The raw material for surface printing is tungsten paste, and the printing thickness is 15μm; The number of layers of the multilayer ceramic substrate is 30.

[0025] Example 3 A corrosion-resistant multilayer ceramic substrate, the raw materials include the following components in parts by weight: 95 parts of aluminum nitride, 6 parts of plasticizer, 8 parts of sintering aid, 5 parts of binder, 3 parts of dispersant, 10 parts of reinforcing agent, and 65 parts of solvent; The reinforcing agent includes nickel powder, titanium powder and yttrium hydride in a mass ratio of 5:2:6; The plasticizer is dibutyl phthalate; The sintering aid is calcium oxide; The binder is polyvinyl butyral; The dispersant is dibutyl phosphate; The solvent is ethanol; A method for preparing a corrosion-resistant multilayer ceramic substrate comprises the following steps: S1. Mix aluminum nitride, plasticizer, sintering aid, dispersant, reinforcing agent and solvent evenly, then add binder and continue mixing until evenly mixed to obtain slurry; S2, tape-casting the slurry, drying it, and obtaining a blank; S3, punching holes in the blank, surface printing, lamination, upper and lower conduction, cutting, sintering at 1680° C., and cooling to obtain a corrosion-resistant multilayer ceramic substrate; The raw material for surface printing is tungsten paste, and the printing thickness is 20μm; The number of layers of the multilayer ceramic substrate is 30.

[0026] Example 4 The only difference between this embodiment and embodiment 3 is that the reinforcing agent in this embodiment includes nickel powder, titanium powder, and yttrium hydride in a mass ratio of 5:2:2.

[0027] Example 5 The only difference between this embodiment and embodiment 3 is that the reinforcing agent in this embodiment includes nickel powder, titanium powder, and yttrium hydride in a mass ratio of 5:2:3.

[0028] Example 6 The only difference between this embodiment and embodiment 3 is that the reinforcing agent in this embodiment includes nickel powder, titanium powder, and yttrium hydride in a mass ratio of 5:2:5.

[0029] Example 7 The only difference between this embodiment and embodiment 6 is that the metal powder in this embodiment is sintered metal powder; The method for preparing the sintered metal powder comprises the following steps: A1, ball-milling nickel powder and titanium powder to obtain a mixture; A2, spark plasma sintering the mixture to obtain sintered metal powder; The ball milling specifically includes first ball milling and then second ball milling; In the first stage of ball milling, the speed was 200 rpm and the time was 2 h; In the second stage of ball milling, the rotation speed was 800 rpm and the time was 1 h; Spark plasma sintering is carried out in an inert gas atmosphere; The inert gas is argon; During spark plasma sintering, the temperature is 1200°C, the pressure is 60MPa, and the time is 15min.

[0030] Example 8 The only difference between this embodiment and embodiment 6 is that the metal powder in this embodiment is sintered metal powder; The method for preparing the sintered metal powder comprises the following steps: A1, ball-milling nickel powder and titanium powder to obtain a mixture; A2, spark plasma sintering the mixture to obtain sintered metal powder; The ball milling specifically includes first ball milling and then second ball milling; In the first stage of ball milling, the rotation speed was 100 rpm and the time was 5 h; In the second stage of ball milling, the rotation speed was 600 rpm and the time was 4 h; Spark plasma sintering is carried out in an inert gas atmosphere; The inert gas is helium; During spark plasma sintering, the temperature is 1000°C, the pressure is 30MPa, and the time is 20min.

[0031] Comparative Example 1 The only difference between this comparative example and Example 3 is that the reinforcing agent in this comparative example includes nickel powder and yttrium hydride in a mass ratio of 7:6.

[0032] Comparative Example 2 The only difference between this comparative example and Example 3 is that the reinforcing agent in this comparative example includes titanium powder and yttrium hydride in a mass ratio of 7:6.

[0033] Comparative Example 3 The only difference between this comparative example and Example 3 is that the reinforcing agent in this comparative example is yttrium hydride.

[0034] Comparative Example 4 The only difference between this comparative example and Example 3 is that the reinforcing agent in this comparative example includes nickel powder and titanium powder in a mass ratio of 5:2.

[0035] Comparative Example 5 The only difference between this comparative example and Example 3 is that this comparative example does not contain a reinforcing agent.

[0036] Experimental Example 1 The corrosion-resistant multilayer ceramic substrates prepared in Examples 1 to 6 and Comparative Examples 1 to 5 were tested for bending strength according to the test method specified in GB / T 6569-2006 "Test Method for Bending Strength of Fine Ceramics", and the test method was three-point bending. The test results are shown in Table 1.

[0037] Table 1 Bending strength test results

[0038] Comparing Example 3 with Comparative Examples 1 to 5, the nickel powder, titanium powder and yttrium hydride in the raw materials of the corrosion-resistant multilayer ceramic substrate of the present invention work synergistically to improve the bending strength of the corrosion-resistant multilayer ceramic substrate.

[0039] Experimental Example 2 After the samples of the corrosion-resistant multilayer ceramic substrates prepared in Examples 6 to 8 were immersed in a 90° C., 20% by mass sulfuric acid solution for 1 hour, a bending strength test after the acid corrosion test was performed according to the above-mentioned bending strength test method. The test results are shown in Table 2.

[0040] Table 2 Acid corrosion test results

[0041] Comparing Examples 7 to 8 with Example 6, it is shown that the use of sintered metal powder instead of metal powder in the present invention improves the corrosion resistance of the corrosion-resistant multilayer ceramic substrate.

[0042] Experimental Example 3 The corrosion-resistant multilayer ceramic substrates prepared in Examples 1 to 8 were tested for dielectric loss using a broadband dielectric impedance meter E4990A at a test frequency of 106 Hz, and the dielectric loss value of the multilayer ceramic substrate is read. The test results are shown in Table 3.

[0043] Table 3 Dielectric loss test results

[0044] The experimental results show that the corrosion-resistant multilayer ceramic substrate of the present invention meets the use requirements.

[0045] The above are only 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 in the protection scope of the present invention.

Claims

1. A corrosion-resistant multilayer ceramic substrate, characterized in that: The raw materials include the following components in parts by weight: 90-100 parts of aluminum nitride, 4-8 parts of plasticizer, 5-10 parts of sintering aid, 3-7 parts of binder, 2-5 parts of dispersant, 5-12 parts of reinforcing agent, and 60-70 parts of solvent; The reinforcing agent includes metal powder and yttrium hydride; The metal powder includes nickel powder and titanium powder.

2. The corrosion-resistant multilayer ceramic substrate according to claim 1, characterized in that: The mass ratio of the nickel powder, titanium powder and yttrium hydride is 5:2:3-5.

3. The corrosion-resistant multilayer ceramic substrate according to claim 1, characterized in that: The metal powder is sintered metal powder.

4. The corrosion-resistant multilayer ceramic substrate according to claim 3, characterized in that: The method for preparing the sintered metal powder comprises the following steps: A1, ball-milling nickel powder and titanium powder to obtain a mixture; A2. The mixed material is subjected to spark plasma sintering to obtain sintered metal powder.

5. The corrosion-resistant multilayer ceramic substrate according to claim 4, characterized in that: The ball milling includes a first stage of ball milling and a second stage of ball milling; During the first stage of ball milling, the rotation speed is 100-200 rpm and the time is 2-5 hours; During the second stage of ball milling, the rotation speed is 600-800 rpm and the time is 1-4 hours.

6. The corrosion-resistant multilayer ceramic substrate according to claim 4, characterized in that: The spark plasma sintering is carried out in an inert gas atmosphere; The inert gas is one of argon and helium.

7. The corrosion-resistant multilayer ceramic substrate according to claim 4, characterized in that: During the spark plasma sintering, the temperature is 1000-1200° C., the pressure is 30-60 MPa, and the time is 15-20 min.

8. The corrosion-resistant multilayer ceramic substrate according to claim 1, characterized in that: The plasticizer includes one of dibutyl phthalate and dioctyl phthalate; The sintering aid includes one of calcium oxide and magnesium oxide; The binder includes one of polyvinyl butyral and polymethyl methacrylate; The dispersant includes one of sodium polyacrylate and dibutyl phosphate; The solvent includes one of n-butanol, isopropanol and ethanol.

9. The method for preparing a corrosion-resistant multilayer ceramic substrate according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Evenly mix aluminum nitride, plasticizer, sintering aid, dispersant, reinforcing agent and solvent, and then add binder to obtain slurry; S2, tape-casting the slurry, and drying it to obtain a blank; S3, punching holes in the blank, and performing surface printing, lamination, upper and lower conduction, cutting, sintering, and cooling to obtain a corrosion-resistant multilayer ceramic substrate.

10. The method for preparing a corrosion-resistant multilayer ceramic substrate according to claim 9, characterized in that: The raw material for surface printing is tungsten paste; During the sintering, the temperature is 1650-1740°C.

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