阅读说明：本技术 低介熔融石英微波介质陶瓷表面金属化方法 (Low dielectric fused quartz microwave dielectric ceramic surface metallization method ) 是由 沈春英 唐志兰 朱田中 于 2019-10-11 设计创作，主要内容包括：本发明提供一种低介熔融石英微波介质陶瓷表面金属化方法,包括以下步骤：步骤1、将熔融石英陶瓷进行预处理,依次采用丙酮、乙醇、去离子水分别超声清洗,然后烘干待用；步骤2、在石英陶瓷表面通过溶胶凝胶-浸渍提拉法制得二氧化钛溶胶膜,再热处理后得到二氧化钛中间层；步骤3、在二氧化钛中间层上丝网印刷制备银层。本发明的方法通过溶胶凝胶-浸渍提拉法引入中间层二氧化钛形成钛酸铋增强银层与中间层的结合力,改善银层与熔融石英陶瓷表面由于线膨胀系数差异太大而结合性差的问题,同时克服了常规丝网印刷金属浆料中过多的玻璃相与基体非晶相反应恶化微波介电性能的缺点。(The invention provides a low dielectric fused quartz microwave dielectric ceramic surface metallization method, which comprises the following steps: step 1, pretreating fused quartz ceramic, respectively ultrasonically cleaning the fused quartz ceramic by sequentially adopting acetone, ethanol and deionized water, and then drying the fused quartz ceramic for later use; step 2, preparing a titanium dioxide sol film on the surface of the quartz ceramic by a sol-gel-dip-coating method, and performing thermal treatment to obtain a titanium dioxide intermediate layer; and 3, preparing a silver layer on the titanium dioxide middle layer by screen printing. According to the method, the titanium dioxide in the middle layer is introduced through the sol-gel dipping and pulling method to form the bismuth titanate so as to enhance the bonding force between the silver layer and the middle layer, the problem of poor bonding property of the silver layer and the fused quartz ceramic surface due to too large difference of linear expansion coefficients is solved, and the defect that the microwave dielectric property is deteriorated due to the reaction of excessive glass phase and matrix amorphous phase in the conventional screen printing metal slurry is overcome.)

1. A method for metalizing the surface of low-dielectric fused quartz microwave dielectric ceramic is characterized by comprising the following steps:

Step 1, pretreating fused quartz ceramic, respectively ultrasonically cleaning the fused quartz ceramic by sequentially adopting acetone, ethanol and deionized water, and then drying the fused quartz ceramic for later use;

Step 2, preparing a titanium dioxide sol film on the surface of the quartz ceramic by a sol-gel-dip-coating method, and performing thermal treatment to obtain a titanium dioxide intermediate layer;

And 3, preparing a silver layer on the titanium dioxide middle layer by screen printing.

2. The method for metalizing the surface of the low-dielectric fused silica microwave dielectric ceramic according to claim 1, wherein the step 2 is a process for preparing the titanium dioxide intermediate layer, which comprises the following steps:

(1) Mixing a mixture of 1: 1-3: mixing 10-30 parts of titanium alkoxide, a complexing agent and an organic solvent, and uniformly mixing by magnetic stirring to prepare a solution A;

(2) and (3) mixing the raw materials in a molar ratio of 1-3: 5-15 of deionized water and an organic solvent are mixed, hydrochloric acid is added to adjust the pH value of the solution to 1-5, and the solution B is prepared by magnetic stirring and mixing uniformly;

(3) Slowly adding the solution B into the solution A at a rate of 20 drops/min, and magnetically stirring the mixed solution for 1 h;

(4) Placing the A, B mixed solution for 1h, adding a chemical drying additive with a molar ratio of 2-8 to the titanium alkoxide, and continuing stirring for 1 h;

(5) and aging for 20h, soaking the fused quartz ceramic into the sol, controlling the pulling speed, preparing a titanium dioxide sol film on the surface of the quartz ceramic, and drying at 70-100 ℃ to obtain a gel film.

3. the method for metalizing the surface of the low-dielectric fused silica microwave dielectric ceramic according to claim 2, wherein the titanium alkoxide is n-butyl titanate or isopropyl titanate.

4. the method for metallizing the surface of a low dielectric fused silica microwave dielectric ceramic according to claim 2, wherein the complexing agent is glacial acetic acid.

5. the method for metallizing the surface of a low-dielectric fused silica microwave dielectric ceramic according to claim 2, wherein the organic solvent is one or more of absolute ethyl alcohol, n-butanol and propanol.

6. The method of claim 2, wherein the chemical drying additive is N-N dimethylformamide or N-N dimethylacetamide.

7. The method for metallizing the surface of a low-k fused silica microwave dielectric ceramic according to claim 1, wherein in the step 3, the process for preparing the surface metallic silver layer by screen printing comprises:

(1) Preparing an organic carrier, which comprises the following components in percentage by mass:

4 to 10 percent of high molecular resin

80-95% of organic solvent

1-4% of organic auxiliary agent

Wherein the preparation of the organic carrier is prepared by heating and stirring the polymer resin, the organic solvent and the organic auxiliary agent in a water bath kettle at the temperature of 70-90 ℃ for 3-5 hours, and cooling for later use;

(2) preparing silver paste, which comprises the following components in percentage by mass:

Wherein, the spherical silver powder, the bismuth oxide powder and the glass powder are uniformly mixed, then the organic carrier is added, and the slurry is uniformly stirred;

(3) Printing metal slurry: printing silver electrode slurry on a titanium dioxide middle layer of fused quartz ceramic by using a 200-mesh silk screen, and drying;

(4) and (3) sintering: sintering at 780-850 deg.c for 1 hr.

8. the method for metallizing the surface of low-dielectric fused quartz microwave dielectric ceramic according to claim 7, wherein the polymer resin is one or more of ethyl cellulose, polyvinyl butyral or polyurethane resin.

9. The method for metallizing the surface of a low-dielectric fused silica microwave dielectric ceramic according to claim 7, wherein the organic solvent in the organic vehicle is one or both of terpineol and turpentine.

10. The method for metalizing the surface of the low dielectric fused quartz microwave dielectric ceramic according to claim 7, wherein the organic auxiliary agent in the organic carrier is one or more of a dispersant, a coupling agent, a leveling agent and the like, wherein the dispersant is BYK-W980, the coupling agent is a silane coupling agent, the leveling agent is castor oil, and the defoaming agent is dimethyl silicone oil.

Technical Field

The invention belongs to the field of microwave dielectric ceramics and microwave components, and particularly relates to a method for metalizing the surface of low-dielectric fused quartz microwave dielectric ceramics.

background

The microwave dielectric ceramic is a key material of microwave devices such as dielectric resonators, dielectric filters, dielectric substrates and the like, and plays an important role in the fields of mobile communication base stations, military radars and the like. With the continuous development of 5G communication technology, the dielectric filter for 5G communication base station is moving highthe frequency and the miniaturization are advanced. The microwave dielectric ceramic with lower dielectric constant is required for high frequency, and the dielectric constant of the low dielectric microwave dielectric ceramic widely used at present is about 9 (Al)₂O₃etc.), and the fused silica microwave dielectric ceramic has an extremely low dielectric constant (3-6), and the quality factor and the frequency temperature coefficient meet the use requirements, so that the dielectric filter can be further high-frequency.

at present, most of 5G communication base stations are dielectric cavity filters, and in the prior art, a high-conductivity metal layer is plated on the inner surface of a metal cavity, and a plurality of mutually coupled dielectric resonators are arranged in the cavity to obtain the dielectric cavity filter, wherein the cavity and the dielectric resonators need to be manufactured respectively and then are connected together in a welding mode and the like. Compared with the traditional metal cavity filter, the dielectric resonator has the advantages of small product volume and high performance, but the process is complicated, the product volume is not small enough, and the high-frequency filter (20-70GHz) is difficult to manufacture. In addition, there are few cavities made of dielectric ceramic materials, such as the one mentioned in patent CN102969549A, which is prepared by plating a metal layer on the inner wall of alumina dielectric ceramic, and the cavity and the resonator both use dielectric ceramic materials to make the dielectric cavity filter have a very good adjustable temperature coefficient, and the cavity and the resonator are also separately manufactured, which is complicated in process and not small enough in volume. If the surface of the fused quartz microwave dielectric ceramic is directly metallized and integrally formed, the process is simple, and compared with the existing dielectric cavity filter, the integrated dielectric waveguide filter is more miniaturized and has higher frequency.

For the surface metallization of fused quartz ceramic, the fused quartz ceramic is an amorphous phase, which is different from general microwave dielectric ceramic or other electronic functional ceramic, the main crystal phase of which is a crystal phase; because of having extremely low linear expansion coefficient (0.54 x 10)^-6v./deg.C), coefficient of linear expansion with metallic silver (19 x 10)^-6/° c) so that the silver layer has poor bonding to the surface of the fused quartz ceramic; by using the conventional screen printing metallization paste, most of the glass phase in the metal layer reacts with the matrix amorphous phase, and the dielectric loss is increased. The prior art Chinese patent CN10264055A discloses conductive silverThe paste and the preparation method thereof, and the surface metallization method of the microwave dielectric ceramic adopt a screen printing conductive silver paste method, and increase the adhesive force of the metallized silver layer on the surface of the microwave dielectric ceramic by optimizing the formula of the conductive silver paste and the screen printing process. The screen printing silver paste is the most common ceramic surface metallization method, the patent mainly aims at titanate-based microwave dielectric ceramics, the content of added glass powder is more than 3% -9%, and excessive glass material can increase the dielectric loss of fused quartz microwave dielectric ceramics; in addition, the coefficient of linear expansion of the silver layer is very different from that of the fused silica microwave dielectric ceramic, so the metallization method in the patent is not suitable for the fused silica microwave dielectric ceramic.

meanwhile, chinese patent CN106747675A discloses a method for metallizing the surface of microwave dielectric ceramic, which comprises depositing a bottom metallized film layer, a middle metallized film layer and a surface welding layer by magnetron sputtering method to prepare three metallized film layers. The microwave medium ceramic matrix in the patent is calcium titanate barium series, magnesium titanate or zirconium titanate series, and the manufacturing process is complex and the cost is high.

Disclosure of Invention

The invention aims to provide a method for metalizing the surface of low-dielectric fused quartz microwave dielectric ceramic, which has simple process and low cost, and the metalized film layer has good adhesion with the fused quartz ceramic.

In order to achieve the purpose, the method for metalizing the surface of the low-dielectric fused quartz microwave dielectric ceramic comprises the following steps:

Step 1, pretreating fused quartz ceramic, respectively ultrasonically cleaning the fused quartz ceramic by sequentially adopting acetone, ethanol and deionized water, and then drying the fused quartz ceramic for later use;

Step 2, preparing a titanium dioxide sol film on the surface of the quartz ceramic by a sol-gel-dip-coating method, and performing thermal treatment to obtain a titanium dioxide intermediate layer;

And 3, preparing a silver layer on the titanium dioxide middle layer by screen printing.

further, in the step 2, the preparation process of the titanium dioxide sol film comprises:

(1) Mixing a mixture of 1: 1-3: mixing 10-30 parts of titanium alkoxide, a complexing agent and an organic solvent, and uniformly mixing by magnetic stirring to prepare a solution A;

(2) and (3) mixing the raw materials in a molar ratio of 1-3: 5-15 of deionized water and an organic solvent are mixed, hydrochloric acid is added to adjust the pH value of the solution to 1-5, and the solution B is prepared by magnetic stirring and mixing uniformly;

(3) slowly adding the solution B into the solution A at a rate of 20 drops/min, and magnetically stirring the mixed solution for 1 h;

(4) Placing the A, B mixed solution for 1h, adding a chemical drying additive with a molar ratio of 2-8 to the titanium alkoxide, and continuing stirring for 1 h;

(5) And aging for 20h, soaking the fused quartz ceramic into the sol, controlling the pulling speed, preparing a titanium dioxide sol film on the surface of the quartz ceramic, and drying at 70-100 ℃ to obtain a gel film.

further, the titanium alkoxide is n-butyl titanate or isopropyl titanate.

Further, the complexing agent is glacial acetic acid.

further, the organic solvent is one or more of absolute ethyl alcohol, n-butyl alcohol and propyl alcohol.

Further, the chemical drying additive is N-N dimethylformamide or N-N dimethylacetamide.

further, in the step 3, the process for preparing the surface metallic silver layer by screen printing comprises:

(1) Preparing an organic carrier, which comprises the following components in percentage by mass:

4 to 10 percent of high molecular resin

80-95% of organic solvent

1-4% of organic auxiliary agent

Wherein the preparation of the organic carrier is prepared by heating and stirring the polymer resin, the organic solvent and the organic auxiliary agent in a water bath kettle at the temperature of 70-90 ℃ for 3-5 hours, and cooling for later use;

(2) Preparing silver paste, which comprises the following components in percentage by mass:

Wherein, the spherical silver powder, the bismuth oxide powder and the glass powder are uniformly mixed, then the organic carrier is added, and the slurry is uniformly stirred;

(3) Printing metal slurry: printing silver electrode slurry on a titanium dioxide middle layer of fused quartz ceramic by using a 200-mesh silk screen, and drying;

(4) and (3) sintering: sintering at 780-850 deg.c for 1 hr.

Further, the polymer resin is one or more of ethyl cellulose, polyvinyl butyral or polyurethane resin.

further, the organic solvent in the organic carrier is one or two of terpineol and turpentine.

further, the organic auxiliary agent in the organic carrier is one or more of a dispersing agent, a coupling agent, a leveling agent and the like, wherein the dispersing agent is BYK-W980, the coupling agent is a silane coupling agent, the leveling agent is castor oil, and the defoaming agent is dimethyl silicone oil.

By the technical scheme, the invention has the beneficial effects that:

1. The titanium dioxide in the middle layer is introduced by a sol-gel dip-coating method, and the linear expansion coefficient of the titanium dioxide is 8.4 to 10^-6/° c) between fused silica (0.54 x 10)^-6V. C) and silver layer (19 x 10)^-6/° c), the bismuth oxide in the silver layer of the surface metal layer and the titanium dioxide in the middle layer form bismuth titanate, so that the binding force between the silver layer and the middle layer is enhanced, and the problem of poor binding property of the silver layer and the surface of the fused quartz ceramic due to too large difference of linear expansion coefficients is solved;

2. The method has less glass phase, overcomes the defect that the microwave dielectric property is deteriorated by the reaction of excessive glass phase and matrix amorphous phase in the conventional screen printing metal slurry;

3. The invention has simple process and low cost, is expected to prepare a miniaturized, high-frequency and integrated dielectric waveguide filter, and is applied to mobile communication base stations such as 5G and the like.

Detailed Description

In order to better understand the technical content of the present invention, specific embodiments are specifically illustrated as follows.

embodiments of the present disclosure are not necessarily intended to include all aspects of the invention. It should be appreciated that the various concepts and embodiments described above, as well as those described in greater detail below, may be implemented in any of numerous ways, as the disclosed concepts and embodiments are not limited to any one implementation. In addition, some aspects of the present disclosure may be used alone, or in any suitable combination with other aspects of the present disclosure.

the invention generally provides a method for metalizing the surface of low-dielectric fused quartz microwave dielectric ceramic based on a sol-gel-dip-coating pulling method and a silk-screen technology, wherein a middle layer of titanium dioxide is introduced through the sol-gel-dip-coating pulling method to form bismuth titanate so as to enhance the bonding force between a silver layer and the middle layer, and the problem of poor bonding property of the silver layer and the surface of the fused quartz ceramic due to too large difference of linear expansion coefficients is solved.

the method for metalizing the surface of the low dielectric fused quartz microwave dielectric ceramic in the preferred embodiment of the invention comprises the following steps:

Step 1, pretreating fused quartz ceramic, respectively ultrasonically cleaning the fused quartz ceramic by sequentially adopting acetone, ethanol and deionized water, and then drying the fused quartz ceramic for later use;

step 2, preparing a titanium dioxide sol film on the surface of the quartz ceramic by a sol-gel-dip-coating method, and performing thermal treatment to obtain a titanium dioxide intermediate layer;

And 3, preparing a silver layer on the titanium dioxide middle layer by screen printing.

Further, in the step 2, the preparation process of the titanium dioxide sol film comprises:

(1) Mixing a mixture of 1: 1-3: mixing 10-30 parts of titanium alkoxide, a complexing agent and an organic solvent, and uniformly mixing by magnetic stirring to prepare a solution A;

(2) and (3) mixing the raw materials in a molar ratio of 1-3: 5-15 of deionized water and an organic solvent are mixed, hydrochloric acid is added to adjust the pH value of the solution to 1-5, and the solution B is prepared by magnetic stirring and mixing uniformly;

(3) slowly adding the solution B into the solution A at a rate of 20 drops/min, and magnetically stirring the mixed solution for 1 h;

(4) Placing the A, B mixed solution for 1h, adding a chemical drying additive with a molar ratio of 2-8 to the titanium alkoxide, and continuing stirring for 1 h;

(5) And aging for 20h, soaking the fused quartz ceramic into the sol, controlling the pulling speed, preparing a titanium dioxide sol film on the surface of the quartz ceramic, and drying at 70-100 ℃ to obtain a gel film.

further, the titanium alkoxide is n-butyl titanate or isopropyl titanate.

Further, the complexing agent is glacial acetic acid.

further, the organic solvent is one or more of absolute ethyl alcohol, n-butyl alcohol and propyl alcohol.

Further, the chemical drying additive is N-N dimethylformamide or N-N dimethylacetamide.

Further, in the step 3, the process for preparing the surface metallic silver layer by screen printing comprises:

(1) preparing an organic carrier, which comprises the following components in percentage by mass:

4 to 10 percent of high molecular resin

80-95% of organic solvent

1-4% of organic auxiliary agent

wherein the preparation of the organic carrier is prepared by heating and stirring the polymer resin, the organic solvent and the organic auxiliary agent in a water bath kettle at the temperature of 70-90 ℃ for 3-5 hours, and cooling for later use;

(2) Preparing silver paste, which comprises the following components in percentage by mass:

Wherein, the spherical silver powder, the bismuth oxide powder and the glass powder are uniformly mixed, then the organic carrier is added, and the slurry is uniformly stirred;

(3) Printing metal slurry: printing silver electrode slurry on a titanium dioxide middle layer of fused quartz ceramic by using a 200-mesh silk screen, and drying;

(4) And (3) sintering: sintering at 780-850 deg.c for 1 hr.

Further, the polymer resin is one or more of ethyl cellulose, polyvinyl butyral or polyurethane resin.

further, the organic solvent in the organic carrier is one or two of terpineol and turpentine.

Further, the organic auxiliary agent in the organic carrier is one or more of a dispersing agent, a coupling agent, a leveling agent and the like, wherein the dispersing agent is BYK-W980, the coupling agent is a silane coupling agent, the leveling agent is castor oil, and the defoaming agent is dimethyl silicone oil.

the foregoing is illustrated in greater detail with reference to more specific embodiments.

[ EXAMPLES one ]

Step 1, ultrasonic cleaning the surface of fused quartz ceramic with the specification of phi 20 multiplied by 2mm for 30min by acetone, ethanol and deionized water respectively in sequence, and drying in an oven at 70-100 ℃ for 1 hour for later use.

Step 2, preparing the titanium dioxide in the middle layer by a sol-gel-dip-coating method, which comprises the following steps:

1) Mixing a mixture of 1: 1.5: 15, mixing tetrabutyl titanate, glacial acetic acid and absolute ethyl alcohol, and uniformly mixing by magnetic stirring to prepare a solution A;

2) Mixing the components in a molar ratio of 2: 10, mixing deionized water and absolute ethyl alcohol, adding hydrochloric acid to adjust the pH value of the solution to 2, and uniformly mixing by magnetic stirring to prepare solution B;

3) Slowly adding the solution B into the solution A at a rate of 20 drops/min, and magnetically stirring the mixed solution for 1 h;

4) placing the A, B mixed solution for 1h, adding N-N dimethylformamide with the molar ratio of 4 to tetrabutyl titanate, and continuing stirring for 1 h;

5) And aging for 20h, immersing the fused quartz ceramic into the sol, controlling the pulling speed, preparing a titanium dioxide sol film on the surface of the quartz ceramic, and drying at 70-100 ℃ to obtain a gel film.

6) And (3) putting the sample into an electric furnace for heat treatment at 600 ℃ for 30min to obtain the titanium dioxide film.

And 3, screen printing on the titanium dioxide in the middle layer to prepare a silver layer.

In some specific examples, the specific steps are as follows:

Firstly, preparing an organic carrier, wherein the organic carrier comprises ethyl cellulose, terpineol, turpentine and a dispersant BYK-W980, and the mass percentage of the organic carrier is 4: 60: 35: 1, placing the organic carrier in a water bath at 80 ℃, heating and stirring for 4 hours, taking out and cooling for later use.

preparing silver electrode slurry, wherein the silver slurry comprises silver powder, an organic carrier and bismuth oxide, and the mass percentage of the silver slurry is 70: 28: 2. uniformly mixing silver powder and bismuth oxide powder, adding an organic carrier, stirring the slurry by using a tin paste stirrer for 5 hours, and standing the silver electrode slurry for 20 hours;

and then, screen printing silver paste with 200 meshes on the titanium dioxide of the middle layer, drying for half an hour in a drying oven at 100 ℃, and sintering for 1 hour at 800 ℃ in a box-type furnace.

In order to more intuitively know the adhesion of the metallized film layer prepared by the method, a blank control group is selected for comparison, the blank control group 1 is free of titanium dioxide in the middle layer, the silver electrode slurry is prepared by mixing silver powder and an organic carrier, and the mass percentage of the silver electrode slurry is 70: 30. adopting ISO2409 to test, adopting a grid cutting method to judge the adhesive force of the metal film layer to the surface of the fused quartz ceramic, and specifically comprising the following steps: adopting the hundred check sword of 11 edges that the sword tooth interval is 1mm to draw into the grid that the interval is 1mm to the metallized film layer, then clear up with the brush along the direction of mar, glue on the metal level with 3M sticky tape, make sticky tape and metal level have good contact, then evenly tear 3M sticky tape fast, if do not have any to drop for 5B, the volume of dropping is 4B between 0 ~ 5%, be 3B between 5 ~ 15%, be 2B between 15 ~ 35%, be 1B between 35 ~ 65%, be 0B within 65%.

Meanwhile, in order to visually understand that the metallized film layer prepared by the method has lower dielectric loss compared with the conventional screen printing method, a blank control group 3 (without middle layer titanium dioxide, silver electrode slurry is silver powder, an organic carrier and glass)The glass powder is prepared by mixing 70 mass percent: 27: 3). The sheet resistance of the metal layer is tested by a four-probe method, and the dielectric constant (epsilon) of a metalized sample on the surface of the fused quartz is tested by an impedance analyzer_r) And dielectric loss (tan δ), the test results are shown in table 1.

TABLE 1 test of the properties of the surface of fused silica ceramics after metallization

[ example two ]

step 1, ultrasonic cleaning the surface of fused quartz ceramic with the specification of phi 20 multiplied by 2mm for 10min by using acetone, ethanol and deionized water respectively in sequence, and drying in an oven at 70-100 ℃ for 1 hour for later use.

Step 2, preparing the titanium dioxide in the middle layer by a sol-gel-dip-coating method, which comprises the following steps:

1) mixing a mixture of 1: 2: 10: 10, mixing isopropyl titanate, glacial acetic acid, absolute ethyl alcohol and n-butyl alcohol, and uniformly stirring and mixing by magnetic force to prepare solution A;

2) Mixing a mixture of 3: 9: 6, mixing the deionized water, the absolute ethyl alcohol and the n-butyl alcohol, adding hydrochloric acid to adjust the pH value of the solution to be 4, and uniformly mixing the solution by magnetic stirring to prepare solution B;

3) slowly adding the solution B into the solution A at a rate of 20 drops/min, and magnetically stirring the mixed solution for 1 h;

4) placing the A, B mixed solution for 1h, adding N-N dimethylacetamide with the molar ratio of 4 to the isopropyl titanate, and continuing stirring for 1 h;

5) and aging for 20h, soaking the fused quartz ceramic into the sol, controlling the pulling speed, preparing a layer of titanium dioxide sol film on the surface of the quartz ceramic, and drying at 70-100 ℃ to obtain a gel film.

6) and (3) putting the sample into an electric furnace for heat treatment at 600 ℃ for 30min to obtain the titanium dioxide film.

Step 3, preparing a silver layer on the titanium dioxide of the middle layer by screen printing

In an alternative example, the specific steps are as follows:

Firstly, preparing an organic carrier, wherein the organic carrier comprises ethyl cellulose, polyvinyl butanol, terpineol, turpentine, castor oil and a silane coupling agent, and the mass percentage of the organic carrier is 6: 2: 50: 40: 1: 1, placing the organic carrier in a water bath at 80 ℃, heating and stirring for 4 hours, taking out and cooling for later use.

preparing silver electrode slurry, wherein the silver slurry comprises silver powder, an organic carrier, bismuth oxide and glass powder, and the mass percentage of the silver electrode slurry is 60: 38: 1.5: 0.5. uniformly mixing silver powder, bismuth oxide powder and glass powder, adding the organic carrier, stirring the slurry by using a tin paste stirrer for 6 hours, and standing the silver electrode slurry for 20 hours.

And then, screen printing silver paste of 200 meshes on the titanium dioxide of the middle layer, drying for half an hour in a drying oven at 100 ℃, and sintering for 1 hour at 820 ℃ in a box-type furnace.

The blank control group 1 is prepared by mixing silver powder and an organic carrier without titanium dioxide in the middle layer, and the mass percentage of the silver electrode slurry is 60: 40. the blank control group 2 is prepared by mixing silver powder, an organic carrier and glass powder without an intermediate layer of titanium dioxide, and the mass percentage of the silver electrode slurry is 60: 39.5: 0.5. blank control 3 was the same as in example 1.

The adhesion of the metal film layer to the surface of the fused silica was tested by the cross-hatch method in example 1, the sheet resistance of the metal layer was tested by the four-probe method, the dielectric constant and the dielectric loss were tested by the impedance analyzer, and the test results are shown in table 2.

TABLE 2 post-metallization performance testing of fused silica ceramic surfaces

from the test results of tables 1 and 2 above, it can be seen that: the method for introducing the titanium dioxide layer in the middle layer provided by the invention is adopted to metalize the surface of the low-dielectric fused quartz ceramic, so that the adhesion between the metal layer on the surface of the quartz ceramic and the quartz ceramic is obviously improved, the sheet resistance meets the expected performance requirements, and the dielectric loss of the low-dielectric fused quartz ceramic is obviously reduced because no glass powder or a small amount of glass powder is introduced.

although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention should be determined by the appended claims.