阅读说明：本技术 一种用于高温共烧陶瓷的填孔浆料 (Hole filling slurry for high-temperature co-fired ceramic ) 是由 张栎方 张巍 胡蝶 马俊峰 朱顺存 于 2021-08-19 设计创作，主要内容包括：本发明公开了一种用于高温共烧陶瓷的填孔浆料,由粉体和有机介质组成,粉体由钨粉和无机相粉体组成,所述钨粉为不同粒径范围的钨粉按下列质量配比组成：0.2-0.8μm粒径钨粉：0％-10％；1-2μm粒径钨粉：70-90％；2-5μm粒径钨粉：0-20％；其中的0代表无限接近于0但不为0,即钨粉由三种不同粒径的钨粉组合而成。本发明还提供行星球磨机预混三辊研磨机轧制制备填孔浆料的方法。本发明提供的填孔浆料可在120N的低压力下一次填孔,小孔饱满,烧结后方阻值在5-10mΩ/□范围内,气密性＜10～(-9)Pa·m～(3)/S。表面及背面平整,填孔处与陶瓷高度差小于±15μm,与陶瓷料带相匹配,解决了陶瓷金属共烧时填孔浆料与陶瓷料带收缩比例不一致的问题。(The invention discloses a pore-filling slurry for high-temperature co-fired ceramic, which consists of powder and an organic medium, wherein the powder consists of tungsten powder and inorganic phase powder, and the tungsten powder is prepared from the following tungsten powder with different particle size ranges in percentage by mass: tungsten powder with a particle size of 0.2-0.8 μm: 0% -10%; 1-2 μm particle size tungsten powder: 70-90%; tungsten powder with particle size of 2-5 μm: 0 to 20 percent; wherein 0 represents infinitely close to 0 but is not 0, namely the tungsten powder is formed by combining tungsten powder with three different particle sizes. The invention also provides a method for preparing the hole-filling slurry by rolling the planet ball mill premixing three-roller grinder. The pore-filling slurry provided by the invention can be used for filling pores at one time under the low pressure of 120N, small pores are full, the resistance value after sintering is within the range of 5-10m omega/□, and the air tightness is less than 10 ‑9 Pa·m 3 and/S. The surface and the back surface are smooth, the height difference between the filling hole and the ceramic is less than +/-15 mu m,the ceramic material belt is matched, so that the problem that the shrinkage proportion of the hole filling slurry and the ceramic material belt is inconsistent when the ceramic metal is co-fired is solved.)

1. The pore-filling slurry for the high-temperature co-fired ceramic is composed of powder and an organic medium, wherein the powder is composed of tungsten powder and inorganic phase powder, and is characterized in that the tungsten powder is composed of tungsten powder with different particle size ranges according to the following mass ratio:

tungsten powder with a particle size of 0.2-0.8 μm: 0% -10%;

1-2 μm particle size tungsten powder: 70-90%;

tungsten powder with particle size of 2-5 μm: 0 to 20 percent;

wherein 0 represents infinitely close to 0 but is not 0, namely the tungsten powder is formed by combining tungsten powder with three different particle sizes.

2. The pore-filling slurry according to claim 1, wherein the pore-filling slurry comprises the following components in parts by mass: 80-90 parts of tungsten powder, 5-10 parts of inorganic phase powder and 5-15 parts of organic medium.

3. The pore-filling slurry of claim 1, wherein the organic medium is made from raw materials consisting of, by mass:

ester solvent: 20-50 parts of

Alcohol solvent: 20-50 parts of

Phthalic acid series plasticizers: 3-10 parts of

Adhesive: 3-10 parts of

The ester solvent is butyl carbitol acetate;

the alcohol solvent is: terpineol or butyl carbitol;

the phthalic acid series plasticizer is dibutyl phthalate or butyl benzyl phthalate;

the binder is polyvinyl butyral or ethyl cellulose.

4. The pore-filling slurry according to claim 1, wherein the inorganic phase powder is alumina, or a mixture of alumina and one or more of magnesia, silica and calcium carbonate.

5. The pore-filling slurry according to claim 4, wherein the alumina, the magnesia, the silica and the calcium carbonate are composed of the following components in percentage by mass:

80-100% of aluminum oxide, 0-10% of magnesium oxide, 0-5% of silicon oxide and 0-5% of calcium carbonate, wherein 0 can be 0, namely when the magnesium oxide, the silicon oxide and the calcium carbonate are all 0, the aluminum oxide is 100%, and the inorganic phase powder is aluminum oxide; or when one or two of the magnesium oxide, the silicon oxide and the calcium carbonate are 0, the mixture is the mixture of the aluminum oxide and one or two of the magnesium oxide, the silicon oxide and the calcium carbonate; when the content of magnesium oxide, silicon oxide and calcium carbonate is not 0, the inorganic phase powder is the mixture of aluminum oxide, magnesium oxide, silicon oxide and calcium carbonate.

6. The pore-filling slurry according to claim 1, wherein the tungsten powder is prepared from tungsten powder with different particle size ranges according to the following mass ratio:

tungsten powder with a particle size of 0.2-0.8 μm: 5% -10%;

1-2 μm particle size tungsten powder: 70-85%;

tungsten powder with particle size of 2-5 μm: 5 to 20 percent.

7. The pore-filling slurry of claim 1, wherein the pore-filling slurry is prepared by the following method: adding tungsten powder, inorganic phase powder and an organic medium into a planetary ball mill in sequence according to a proportion, discharging slurry after ball milling of the planetary ball mill, and rolling by using a three-roll grinder; dispersing to the fineness of below 12 microns to prepare the pore-filling slurry.

8. The pore-filling slurry of claim 7, wherein the pore-filling slurry is prepared by the following method: adding tungsten powder, inorganic phase powder and an organic medium into a planetary ball mill in sequence according to a proportion, performing ball milling for 24-48 hours under 35-45HZ of the planetary ball mill, discharging slurry, and rolling for 4-7 times by using a three-roll grinding machine, wherein the gap between the rolls is 10-30 mu m; dispersing to the fineness of below 12 microns to prepare the pore-filling slurry.

9. The use of the pore-filling slurry according to claim 1 for high-temperature co-fired ceramics, characterized in that the method of application is: and filling small holes in the ceramic material belt with the hole filling slurry, filling the small holes at 120N pressure for the first time, wherein the small holes are uniform and full, heating the mixture to 1600 ℃ in a hydrogen and nitrogen atmosphere, sintering the mixture for 2 to 3 hours, cooling the mixture along with a furnace, and enabling the height difference between the filled holes and the ceramic to be less than +/-15 mu m.

Technical Field

The invention relates to a pore-filling slurry for high-temperature co-fired ceramic metallization.

Background

The SMD ceramic packaging base is a three-dimensional interconnection structure formed by overlapping ceramic green sheets printed with conductive patterns and punched with conductive holes in a certain order and processing the ceramic green sheets by an atmosphere protection sintering process. Common through hole filling methods are print via filling and squeeze via filling. The extrusion mode is used for filling holes, the pressure is high, after multiple times of hole filling, the viscosity of slurry is increased, the hole filling difficulty is increased, the hole filling quality is reduced, and the phenomenon of slurry diffusion around filled through holes is serious. The printing type hole filling has relatively stable slurry property and small slurry loss, but the phenomenon of small hole fullness after one-time hole filling is easy to occur. The small holes filled by the two modes are easy to be unmatched with the ceramic material belt after being sintered.

Therefore, it is necessary to improve the pore-filling slurry, and the pore-filling slurry is prepared, so that the pores can be filled at a time under low pressure, small pores are full, and no obvious concave and convex parts exist after sintering, and the pore-filling slurry is matched with the ceramic material belt.

Disclosure of Invention

The invention aims to provide pore-filling slurry which can be used for filling pores at a low pressure (120N) for one time, has full pores, has no obvious concave and convex parts after sintering and is matched with a ceramic material belt.

The technical scheme adopted by the invention is as follows:

the pore-filling slurry for the high-temperature co-fired ceramic is composed of powder and an organic medium, wherein the powder is composed of tungsten powder and inorganic phase powder, and the tungsten powder is composed of tungsten powder with different particle size ranges according to the following mass ratio:

tungsten powder with a particle size of 0.2-0.8 μm: 0% -10%;

1-2 μm particle size tungsten powder: 70-90%;

tungsten powder with particle size of 2-5 μm: 0 to 20 percent.

Wherein 0 represents infinitely close to 0 but not 0, that is, the tungsten powder is formed by combining tungsten powders with three different particle sizes.

Specifically, the pore-filling slurry comprises the following components in parts by weight: 80-90 parts of tungsten powder, 5-10 parts of inorganic phase powder and 5-15 parts of organic medium; preferably: 81-87 parts of tungsten powder, 6-8 parts of inorganic phase powder and 7-11 parts of organic medium.

Further, the mass ratio of the powder to the organic medium is preferably 8-13: 1.

The organic medium is prepared from the following raw materials in parts by mass:

ester solvent: 20-50 parts of

Alcohol solvent: 20-50 parts of

Phthalic acid series plasticizers: 3-10 parts of

Adhesive: 3-10 parts of

The ester solvent is butyl carbitol acetate;

the alcohol solvent is: terpineol or butyl carbitol;

the phthalic acid series plasticizer is dibutyl phthalate or butyl benzyl phthalate;

the binder is polyvinyl butyral or ethyl cellulose.

Further, the powder preferably comprises metal tungsten powder and inorganic phase powder according to a mass ratio of 9: 1-15: 1, the components of the composition are mixed,

the inorganic phase powder is alumina, or the mixture of alumina and one or more than two of magnesia, silica and calcium carbonate, and specifically, the alumina, the magnesia, the calcium carbonate and the silica are composed of the following components in percentage by mass:

80-100% of aluminum oxide, 0-10% of magnesium oxide, 0-5% of silicon oxide and 0-5% of calcium carbonate, wherein 0 can be 0, namely when the magnesium oxide, the silicon oxide and the calcium carbonate are all 0, the aluminum oxide is 100%; or when one or two of magnesium oxide, silicon oxide and calcium carbonate is 0, the mixture is the mixture of aluminum oxide and other two or one; when the content of magnesium oxide, silicon oxide and calcium carbonate is not 0, the inorganic phase powder is the mixture of aluminum oxide, magnesium oxide, silicon oxide and calcium carbonate.

Further, the composition of the inorganic phase powder is preferably: 90-99% of aluminum oxide, 0-5% of magnesium oxide, 0.5-5% of silicon oxide and 0-1% of calcium carbonate.

The particle size of the inorganic phase powder is usually 1-3 microns;

the particle shape of the tungsten powder is one or more of spherical, flaky and scaly particles.

Further, the tungsten powder is preferably tungsten powder with different particle size ranges, and comprises the following components in percentage by mass:

tungsten powder with a particle size of 0.2-0.8 μm: 5% -10%;

1-2 μm particle size tungsten powder: 70-85%;

tungsten powder with particle size of 2-5 μm: 5 to 20 percent.

The invention also provides a preparation method of the pore-filling slurry, and the pore-filling slurry can be prepared by the following steps: adding tungsten powder, inorganic phase powder and an organic medium into a planetary ball mill in sequence according to a proportion, discharging slurry after ball milling of the planetary ball mill, and rolling by using a three-roll grinder; dispersing to the fineness of below 12 microns to prepare the pore-filling slurry.

More specifically, the method may be:

adding tungsten powder, inorganic phase powder and an organic medium into a planetary ball mill in sequence according to a proportion, performing ball milling for 24-48 hours under 35-45HZ of the planetary ball mill, discharging slurry, and rolling for 4-7 times by using a three-roll grinding machine, wherein the gap between the rolls is 10-30 mu m; dispersing to the fineness of below 12 microns to prepare the pore-filling slurry.

The organic medium is prepared by uniformly mixing an ester solvent, an alcohol solvent and a phthalic acid series plasticizer according to a ratio at the temperature of 80-90 ℃, adding a binder, continuously heating and stirring for 6-8 hours, and cooling to room temperature.

The invention also provides an application of the pore-filling slurry in high-temperature co-fired ceramics, and the application method comprises the following steps: and filling small holes in the ceramic material belt with the hole filling slurry, filling the small holes at 120N pressure for the first time, wherein the small holes are uniform and full, heating the mixture to 1600 ℃ in a hydrogen and nitrogen atmosphere, sintering the mixture for 2 to 3 hours, cooling the mixture along with a furnace, and enabling the height difference between the filled holes and the ceramic to be less than +/-15 mu m. In the hydrogen and nitrogen atmosphere, the volume ratio of hydrogen to nitrogen is 3: 1.

According to the invention, through the combination and proportion of tungsten powder with different particle sizes, the hole can be filled at one time under low pressure (120N), the small hole is full, and the air tightness is less than 10 after sintering^-9Pa·m³(S), the surface and the back are flat without obvious concave and convex, the height difference between the filling hole and the ceramic is less than +/-15 mu m, and the filling hole is matched with the ceramic material beltThe problem that the shrinkage proportion of the hole filling slurry and the ceramic material belt is inconsistent when the ceramic metal is co-fired is solved. And the pore filling slurry matched with tungsten powder with various particle sizes also improves the conduction performance of small pores, and the sheet resistance of the pore filling slurry is 5-10m omega/□, which is reduced by 25-50% compared with the slurry in the prior art. The invention also improves the preparation process, improves the stability of the pore-filling slurry, keeps the viscosity and the fineness of the slurry stable in the storage process of the pore-filling slurry, and solves the problems of rapid change of the viscosity and the fineness, layering and solid-liquid separation in the storage of the slurry prepared by the conventional process.

Detailed Description

The technical solution of the present invention is further illustrated by the following specific examples, but the scope of the present invention is not limited thereto.

In the embodiment of the invention, the particle sizes of the alumina, the magnesia, the silica and the calcium carbonate are 1-3 mu m.

Comparative example 1:

the organic medium formula comprises: 40 parts of terpineol, 50 parts of butyl carbitol acetate, 5 parts of dibutyl phthalate and 5 parts of ethyl cellulose;

in a 90 ℃ oil bath kettle, evenly mixing terpineol, butyl carbitol acetate and dibutyl phthalate according to a certain proportion, adding ethyl cellulose according to a certain proportion, continuously heating and stirring for 6 hours, and cooling to room temperature to obtain an organic medium;

87 parts of tungsten powder (0.2-0.8 mu m), 6 parts of inorganic phase substances (96% of aluminum oxide, 2.5% of magnesium oxide, 1% of calcium carbonate and 0.5% of silicon oxide) and 7 parts of organic medium are sequentially added into the planetary ball mill according to the proportion, the mixture is ball-milled for 24 hours by the planetary ball mill at the frequency of 45Hz, and then is discharged, rolled for 5 times by a three-roll mill at the roll interval of 15 mu m, and dispersed until the fineness is below 12 mu m. The slurry is used for filling small holes with the diameter of 0.2mm on a ceramic material belt with the thickness of 0.254mm, and the small holes are uniformly filled at one time under the pressure of 120N. Under the atmosphere of hydrogen and nitrogen (the volume ratio of hydrogen to nitrogen is 3:1), heating from room temperature to 800 ℃ at 1 ℃/min, heating from 800 ℃ to 1600 ℃ at 2 ℃/min, sintering at 1600 ℃ for 2 hours, cooling along with the furnace, and lowering the hole filling position by 20 microns compared with the ceramic position.

Comparative example 2:

the organic medium formula comprises: 40 parts of terpineol, 50 parts of butyl carbitol acetate, 5 parts of dibutyl phthalate and 5 parts of ethyl cellulose;

in a 90 ℃ oil bath kettle, evenly mixing terpineol, butyl carbitol acetate and dibutyl phthalate according to a certain proportion, adding ethyl cellulose according to a certain proportion, continuously heating and stirring for 6 hours, and cooling to room temperature to obtain an organic medium;

87 parts of tungsten powder (1-2 mu m), 6 parts of inorganic phase substances (96% of aluminum oxide, 2.5% of magnesium oxide, 1% of calcium carbonate and 0.5% of silicon oxide) and 7 parts of organic medium are sequentially added into the planetary ball mill according to the proportion, the mixture is ball-milled for 24 hours by the planetary ball mill at the frequency of 45Hz and then is discharged, the mixture is rolled for 5 times by a three-roll mill at the roll interval of 15 mu m, and the mixture is dispersed until the fineness is below 12 mu m. The slurry is used for filling small holes with the diameter of 0.2mm on a ceramic material belt with the thickness of 0.254mm, and the small holes are uniformly filled at one time under the pressure of 120N. Under the atmosphere of hydrogen and nitrogen (the volume ratio of hydrogen to nitrogen is 3:1), heating from room temperature to 800 ℃ at 1 ℃/min, heating from 800 ℃ to 1600 ℃ at 2 ℃/min, sintering at 1600 ℃ for 2 hours, cooling along with the furnace, and filling holes 18 microns higher than the ceramic.

Comparative example 3:

the organic medium formula comprises: 40 parts of terpineol, 50 parts of butyl carbitol acetate, 5 parts of dibutyl phthalate and 5 parts of ethyl cellulose;

in a 90 ℃ oil bath kettle, evenly mixing terpineol, butyl carbitol acetate and dibutyl phthalate according to a certain proportion, adding ethyl cellulose according to a certain proportion, continuously heating and stirring for 6 hours, and cooling to room temperature to obtain an organic medium;

87 parts (2-5 mu m) of tungsten powder, 6 parts (96% of aluminum oxide, 2.5% of magnesium oxide, 1% of calcium carbonate and 0.5% of silicon oxide) of inorganic phase substances and 7 parts of organic medium are sequentially added into the planetary ball mill according to the proportion, the mixture is ball-milled for 24 hours by the planetary ball mill under the frequency of 45Hz and then is discharged, the mixture is rolled for 5 times under the roller spacing of a three-roller mill of 15 mu m, and the mixture is dispersed until the fineness is below 12 mu m. The slurry is used for filling small holes with the diameter of 0.2mm on a ceramic material belt with the thickness of 0.254mm, and the small holes are uniformly filled at one time under the pressure of 120N. Under the atmosphere of hydrogen and nitrogen (the volume ratio of hydrogen to nitrogen is 3:1), heating from room temperature to 800 ℃ at 1 ℃/min, heating from 800 ℃ to 1600 ℃ at 2 ℃/min, sintering at 1600 ℃ for 2 hours, cooling along with the furnace, and filling holes with the height of 30 microns higher than that of the ceramic.

Comparative example 4:

the organic medium formula comprises: 40 parts of terpineol, 50 parts of butyl carbitol acetate, 5 parts of dibutyl phthalate and 5 parts of ethyl cellulose;

in a 90 ℃ oil bath kettle, evenly mixing terpineol, butyl carbitol acetate and dibutyl phthalate according to a certain proportion, adding ethyl cellulose according to a certain proportion, continuously heating and stirring for 6 hours, and cooling to room temperature to obtain an organic medium;

87 parts of tungsten powder (0.2-0.8 mu m 5%, 1-2 mu m 80% and 2-5 mu m 15%), 6 parts of inorganic phase substances (aluminum oxide 96%, magnesium oxide 2.5%, calcium carbonate 1% and silicon oxide 0.5%) and 7 parts of organic medium are added into a stirrer in sequence according to the proportion, fully stirred, rolled for 5 times by a three-roll grinder with the roll spacing of 15 mu m, and dispersed until the fineness is below 12 mu m. The slurry is used for filling small holes with the diameter of 0.2mm on a ceramic material belt with the thickness of 0.254mm, the small holes are filled at one time under the pressure of 120N and are sunken, the small holes are filled at one time under the pressure of 150N, and the small holes are uniform and full. Under the atmosphere of hydrogen and nitrogen (the volume ratio of hydrogen to nitrogen is 3:1), heating from room temperature to 800 ℃ at 1 ℃/min, heating from 800 ℃ to 1600 ℃ at 2 ℃/min, sintering at 1600 ℃ for 2 hours, cooling along with the furnace, and filling holes 12 microns lower than the ceramic.

Comparative example 5:

the organic medium formula comprises: 40 parts of terpineol, 50 parts of butyl carbitol acetate, 5 parts of dibutyl phthalate and 5 parts of ethyl cellulose;

in a 90 ℃ oil bath kettle, evenly mixing terpineol, butyl carbitol acetate and dibutyl phthalate according to a certain proportion, adding ethyl cellulose according to a certain proportion, continuously heating and stirring for 6 hours, and cooling to room temperature to obtain an organic medium;

87 parts of tungsten powder (0.2-0.8 mu m 5%, 1-2 mu m 80%, 2-5 mu m 15%), 6 parts of inorganic phase substances (aluminum oxide 96%, magnesium oxide 2.5%, calcium carbonate 1%, silicon oxide 0.5%), alcohol and powder in a ratio of 1:2 are sequentially added into a roller ball milling tank according to the proportion, the mixture is subjected to roller ball milling for 24 hours, slurry is discharged, the powder is dried, the powder is sieved by a 300-mesh sieve, the mixed powder and 7 parts of organic medium are added into a stirrer, the mixture is fully stirred, the mixture is rolled for 5 times by a three-roller mill at a roller spacing of 15 mu m, and the mixture is dispersed until the fineness is below 12 mu m. The pressure of 120N is used for filling once, the small holes are sunken, the pressure of 120N is used for filling twice, and the small holes are uniform and full. Under the atmosphere of hydrogen and nitrogen (the volume ratio of hydrogen to nitrogen is 3:1), heating from room temperature to 800 ℃ at 1 ℃/min, heating from 800 ℃ to 1600 ℃ at 2 ℃/min, sintering at 1600 ℃ for 2 hours, cooling along with the furnace, and filling holes with a depth 14 microns lower than that of the ceramic.

Example 1:

the organic medium formula comprises: 40 parts of terpineol, 50 parts of butyl carbitol acetate, 5 parts of dibutyl phthalate and 5 parts of ethyl cellulose;

in a 90 ℃ oil bath kettle, evenly mixing terpineol, butyl carbitol acetate and dibutyl phthalate according to a certain proportion, adding ethyl cellulose according to a certain proportion, continuously heating and stirring for 6 hours, and cooling to room temperature to obtain an organic medium;

87 parts of tungsten powder (0.2-0.8 mu m 5%, 1-2 mu m 80%, 2-5 mu m 15%), 6 parts of inorganic phase substances (aluminum oxide 96%, magnesium oxide 2.5%, calcium carbonate 1%, silicon oxide 0.5%) and 7 parts of organic medium are sequentially added into a planetary ball mill according to the proportion, the mixture is ball-milled for 24 hours under the frequency of 45Hz by the planetary ball mill, slurry is discharged, the mixture is rolled for 5 times under the roller interval of 15 mu m of a three-roller mill, and the mixture is dispersed until the fineness is below 12 mu m. The slurry is used for filling 1736 small holes with the diameter of 0.2mm on a flake ceramic material strip with the length of 110mm X110mm and the thickness of 0.254mm, and the small holes are uniformly filled under the pressure of 120N. Under the atmosphere of hydrogen and nitrogen (the volume ratio of hydrogen to nitrogen is 3:1), heating from room temperature to 800 ℃ at 1 ℃/min, heating from 800 ℃ to 1600 ℃ at 2 ℃/min, sintering at 1600 ℃ for 2 hours, cooling along with the furnace, and lowering the hole filling position by 8 microns than that of the ceramic.

Example 2:

the organic medium formula comprises: 50 parts of terpineol, 40 parts of butyl carbitol acetate, 4 parts of dibutyl phthalate and 6 parts of ethyl cellulose;

in a 90 ℃ oil bath kettle, evenly mixing terpineol, butyl carbitol acetate and dibutyl phthalate according to a certain proportion, adding ethyl cellulose according to a certain proportion, continuously heating and stirring for 6 hours, and cooling to room temperature to obtain an organic medium;

adding 85 parts (0.2-0.8 mu m 10%, 1-2 mu m 85%, 2-5 mu m 5%) of tungsten powder, 6 parts (aluminum oxide 94%, magnesium oxide 3.5%, calcium carbonate 1%, silicon oxide 1.5%) of inorganic phase substances and 9 parts of organic medium into a planetary ball mill in sequence according to a proportion, carrying out ball milling for 24 hours by the planetary ball mill at a frequency of 40 Hz, discharging slurry, rolling for 4 times at a roller interval of 20 mu m by a three-roller mill, and dispersing until the fineness is below 12 mu m. The slurry is used for filling small holes with the diameter of 0.2mm on a ceramic material belt with the thickness of 0.254mm, and the small holes are uniformly filled at one time under the pressure of 120N. Under the atmosphere of hydrogen and nitrogen (the volume ratio of hydrogen to nitrogen is 3:1), heating from room temperature to 800 ℃ at 1 ℃/min, heating from 800 ℃ to 1600 ℃ at 2 ℃/min, sintering at 1600 ℃ for 2 hours, cooling along with the furnace, and enabling the hole filling position to be 9 micrometers higher than the ceramic position.

Example 3:

the organic medium formula comprises: 42 parts of butyl carbitol, 42 parts of butyl carbitol acetate, 8 parts of butyl benzyl phthalate and 8 parts of polyvinyl butyral;

uniformly mixing butyl carbitol, butyl carbitol acetate and butyl benzyl phthalate in proportion in a 90 ℃ oil bath kettle, adding a certain proportion of polyvinyl butyral, continuously heating and stirring for 6 hours, and cooling to room temperature to obtain an organic medium;

81 parts of tungsten powder (0.2-0.8 mu m 10%, 1-2 mu m 70% and 2-5 mu m 20%) and 8 parts of inorganic phase substance (aluminum oxide 96% and silicon oxide 4%) and 11 parts of organic medium are sequentially added into the planetary ball mill according to the proportion, the mixture is ball-milled for 24 hours by the planetary ball mill under the frequency of 40 Hz and then is discharged, and the mixture is rolled for 6 times under the roller spacing of a three-roller mill of 30 mu m and dispersed until the fineness is below 12 mu m. The slurry is used for filling small holes with the diameter of 0.2mm on a ceramic material belt with the thickness of 0.254mm, and the small holes are uniformly filled at one time under the pressure of 120N. Under the atmosphere of hydrogen and nitrogen (the volume ratio of hydrogen to nitrogen is 3:1), heating from room temperature to 800 ℃ at 1 ℃/min, heating from 800 ℃ to 1600 ℃ at 2 ℃/min, sintering at 1600 ℃ for 2 hours, cooling along with the furnace, and making the hole filling position 10 micrometers higher than the ceramic position.

The pore-filling effect, the pore-filling protrusion height test result, and the pore-filling paste sheet resistance test result of the pore-filling pastes prepared in examples 1 to 3 and comparative examples 1 to 5 are shown in table 1 below. The pore-filling slurries prepared in examples 1 to 3 and comparative examples 1 to 5 were stored while being left to stand, sampled every month to measure the viscosity and fineness thereof, and the results are shown in tables 2 and 3 below.

The sheet resistance test is carried out according to the determination of sheet resistance of the method for testing noble metal slurry for microelectronic technology, standard number: the method of GB/T17473.3-2008.

TABLE 1

As can be seen from Table 1, examples 1-3 and comparative examples 1-3 were all prepared by a preparation process of a planetary ball mill pre-mixing three-roll mill, and the obtained hole-filling slurry was subjected to hole filling once under a pressure of 120N, and the small holes were filled and the edges were smooth. However, the tungsten powder with a single particle size is adopted in the comparative examples 1 to 3, the matching performance of the pore-filling slurry and the green body after sintering is poor, and the protruding height is unqualified. In the examples 1 to 3, tungsten powder with various particle size combinations is adopted, the protruding height is qualified, and the matching performance is good.

The formulations of comparative examples 4 to 5 were the same as in the examples, but the preparation process was different. The comparative examples 4-5 adopt the existing conventional process, the preparation process of the comparative example 4 is that the powder and the organic medium are directly stirred by a stirrer and then rolled by a three-high mill, the preparation process of the comparative example 5 is that the powder is added with alcohol to be ball-milled by a roller, and then slurry is produced, dried and sieved, and the mixed powder is added with the organic medium to be stirred and then rolled by the three-high mill, the two processes have poor hole filling effect, the small hole of the next hole filling of 120N can be sunken, and secondary hole filling is needed or the hole filling is carried out for 150N under higher pressure. However, the slurries of comparative examples 4 to 5 had better compatibility with the green stock and the protrusion height was acceptable.

From the test results of the sheet resistance of the pore-filling slurry, the sheet resistance of the slurry in the application is adopted in the examples 1-3 and the comparative examples 4 and 5, the sheet resistance value is in the range of 5-10m omega/□, and compared with the comparative examples 1-3, the sheet resistance is obviously reduced, and the reduction ratio is up to 50%. The reduction of the sheet resistance of the pore-filling slurry is beneficial to improving the conduction performance of the small holes, and the upper layer and the lower layer can be better interconnected and conducted during wiring.

TABLE 2

TABLE 3

As can be seen from table 2 and table 3, in comparative examples 1 to 3 and examples 1 to 3, the preparation process of the planetary ball mill premixing three-roll mill rolling is adopted, the viscosity and the fineness of the pore-filling slurry are stable and the amplitude of the pore-filling slurry is small during storage for three months, and in comparative example 4, the viscosity and the fineness of the pore-filling slurry prepared in comparative example 5 are unstable and the amplitude of the pore-filling slurry is large. After the viscosity and the fineness are increased, the difficulty of hole filling is increased, the hole filling quality is deteriorated, and even the slurry cannot be normally used.