阅读说明：本技术 电子陶瓷基片一体烧结方法 (Integrated sintering method for electronic ceramic substrate ) 是由 尚华 王刚 段冰 林贵洪 于 2021-09-22 设计创作，主要内容包括：本发明涉及电子陶瓷材料制备工艺领域,尤其是一种有效提高电子陶瓷基片品质,同时由于陶瓷基片熟烧和复平两个工序合并为一个烧结工序,还可以节能减排,又能缩短生产制造周期的电子陶瓷基片一体烧结方法,包括如下步骤：a、陶瓷基片坯体的排胶脱脂处理；b、钨钼片间夹陶瓷基片的设置；c、还原气氛炉的烧结；d、熟烧和复平一体烧结,分别取出钨钼片及陶瓷基片得到产品。本方法烧结后,产品的翘曲度可以直接达到0.05mm以内,陶瓷体积密度不受压烧影响而降低,烧结后基片表面粗糙度可直接达到0.1μm以下,整体产品性能优良,满足高端陶瓷基片需求。本发明尤其适用于电子陶瓷基片一体烧结工艺之中。(The invention relates to the field of electronic ceramic material preparation processes, in particular to an electronic ceramic substrate integrated sintering method which can effectively improve the quality of an electronic ceramic substrate, can save energy and reduce emission and can shorten the production and manufacturing period due to the fact that a ceramic substrate is subjected to mature firing and re-flattening and is combined into a sintering process, and comprises the following steps: a. glue removing and degreasing treatment of the ceramic substrate blank; b. arranging a ceramic substrate between tungsten-molybdenum sheets; c. sintering in a reducing atmosphere furnace; d. and (4) performing cooking, sintering and flattening integrated sintering, and respectively taking out the tungsten-molybdenum sheet and the ceramic substrate to obtain a product. After the sintering, the warping degree of the product can be directly within 0.05mm, the ceramic volume density is not reduced by the influence of pressure sintering, the surface roughness of the substrate after sintering can be directly below 0.1 mu m, the overall product performance is excellent, and the requirement of a high-end ceramic substrate is met. The invention is especially suitable for the integral sintering process of the electronic ceramic substrate.)

1. The integral sintering method of the electronic ceramic substrate is characterized by comprising the following steps of:

a. glue removing and degreasing treatment of the ceramic substrate blank: placing the formed ceramic substrate into a glue discharging and degreasing kiln, and performing glue discharging and degreasing treatment on the ceramic substrate, wherein the glue discharging, degreasing and sintering temperature range is 1300-1400 ℃;

B. arranging a ceramic substrate sandwiched between tungsten and molybdenum sheets: the sintering kiln tool adopts a high-temperature tungsten-molybdenum plate, wherein the size of the tungsten-molybdenum plate is slightly larger than that of the ceramic substrate, the green body single piece after the ceramic substrate is subjected to glue removal and degreasing is placed on the tungsten-molybdenum plate, a layer of tungsten-molybdenum plate is covered on the ceramic substrate, the next ceramic substrate is placed on the previous tungsten-molybdenum plate, and the operation is repeated and circulated in sequence, wherein the number of stacked layers ensures that the ceramic substrate at the bottommost part cannot be crushed;

C. sintering in a reducing atmosphere furnace: putting the well placed kiln furniture and the sintered whole body of the ceramic into a kiln with a reducing atmosphere or a protective atmosphere for sintering at a high temperature;

D. and (3) cooking, sintering and flattening integrated sintering: in the sintering process, the highest sintering temperature range of the ceramic substrate is 1620-1700 ℃, the high-temperature heat preservation time range is 4-5h, and after sintering and cooling, the tungsten-molybdenum plate and the ceramic substrate are respectively taken out to obtain a product.

2. An electronic ceramic substrate integral sintering method as claimed in claim 1, characterized in that: in the step b, the thickness of the tungsten-molybdenum plate is 2-3 mm.

3. An electronic ceramic substrate integral sintering method as claimed in claim 1, characterized in that: in the step b, the surface roughness range of the tungsten-molybdenum plate is Ra0.2-0.4 μm.

4. An electronic ceramic substrate integral sintering method as claimed in claim 1, characterized in that: in the step b, the warping degree of the tungsten-molybdenum plate is less than or equal to 0.1 mm.

5. An integral sintering method of an electronic ceramic substrate as claimed in claim 1, 2, 3 or 4, characterized in that: in the step b, when the thickness of the final product is within 0.5mm, the number of the ceramic substrates placed in the layer is not more than 5, namely the number of the tungsten-molybdenum plates is not more than 6.

6. An integral sintering method of an electronic ceramic substrate as claimed in claim 1, 2, 3 or 4, characterized in that: in the step b, when the thickness of the final product is within 0.5-1mm, the number of the ceramic substrates to be placed is not more than 10, namely, the number of the tungsten-molybdenum plates is not more than 11.

7. An integral sintering method of an electronic ceramic substrate as claimed in claim 1, 2, 3 or 4, characterized in that: in the step c, the gas in the reducing atmosphere is a mixed gas of hydrogen and nitrogen and hydrogen.

8. An integral sintering method of an electronic ceramic substrate as claimed in claim 1, 2, 3 or 4, characterized in that: in the step c, the gas in the protective atmosphere is nitrogen and other inert gases.

9. An integral sintering method of an electronic ceramic substrate as claimed in claim 1, 2, 3 or 4, characterized in that: in the step c, the fluctuation range of the temperature difference interval of the kiln in the high-temperature sintering state is within 30 ℃.

Technical Field

The invention relates to the field of electronic ceramic material preparation processes, in particular to an integrated sintering method of an electronic ceramic substrate.

Background

In recent years, electric vehicles, semiconductor illumination aerospace, satellite communication and the like enter a high-speed development stage, electronic devices of the electronic devices have large working current, high temperature and high frequency, higher requirements are put forward on chip carriers in order to meet the working stability of the devices and circuits, and ceramic substrates have the advantages of excellent thermal performance, microwave performance, mechanical performance, high reliability and the like and can be widely applied to the fields. No matter the traditional alumina and beryllium oxide ceramic substrate or the silicon nitride and aluminum nitride ceramic substrate which is hot in the current market, the ceramic substrate which is subjected to ceramic formation is required to have better flatness so as to be convenient for subsequent processing, the thickness of the ceramic substrate is basically required to be within 1mm, and the flatness is not more than 10% of the thickness of the ceramic.

The manufacturing process of the existing ceramic substrate basically adopts a mode of adding flattening sintering after firing, and flattening is carried out by a mode of weighting and pressing firing after the ceramic substrates are stacked, and the mode mainly has several problems at present:

firstly, after the ceramic substrate is fired, the warpage degrees are different, the pressing firing after lamination cannot play a leveling role on a substrate with serious part warpage, so that the leveling effect is uneven, the substrate with serious part warpage needs to be leveled and sintered again or even three times, secondary development of ceramic crystal grains is necessarily brought by multiple sintering, the crystal grains are too large, and the mechanical strength of the ceramic substrate is influenced.

Secondly, the leveling occupies kiln resources, the production and preparation period is increased by multiple leveling, the labor and energy consumption cost in the production process is increased, the overall efficiency is not high, finally, a lamination pressing and burning mode is adopted, the flatness of the substrate after leveling is basically within 0.2mm, the requirement of the current high-performance thin film circuit substrate within 0.05mm cannot be met, the leveling temperature control range is strict, ceramic substrates are easy to stick when the temperature is too high, and the leveling effect cannot be achieved when the temperature is too low and leveling sintering is carried out.

Disclosure of Invention

The invention aims to solve the technical problem of providing an integral sintering method of an electronic ceramic substrate, which can effectively improve the quality of the electronic ceramic substrate, save energy and reduce emission and shorten the production and manufacturing period because the two procedures of the ceramic substrate cooking and leveling are combined into one sintering procedure.

The technical scheme adopted by the invention for solving the technical problems is as follows: the integral sintering method of the electronic ceramic substrate comprises the following steps: a. glue removing and degreasing treatment of the ceramic substrate blank: placing the formed ceramic substrate into a glue discharging and degreasing kiln, and performing glue discharging and degreasing treatment on the ceramic substrate, wherein the glue discharging, degreasing and sintering temperature range is 1300-1400 ℃; b. arranging a ceramic substrate sandwiched between tungsten and molybdenum sheets: the sintering kiln tool adopts a high-temperature tungsten-molybdenum plate, wherein the size of the tungsten-molybdenum plate is slightly larger than that of the ceramic substrate, the green body single piece after the ceramic substrate is subjected to glue removal and degreasing is placed on the tungsten-molybdenum plate, a layer of tungsten-molybdenum plate is covered on the ceramic substrate, the next ceramic substrate is placed on the previous tungsten-molybdenum plate, and the operation is repeated and circulated in sequence, wherein the number of stacked layers ensures that the ceramic substrate at the bottommost part cannot be crushed; c. sintering in a reducing atmosphere furnace: putting the well placed kiln furniture and the sintered whole body of the ceramic into a kiln with a reducing atmosphere or a protective atmosphere for sintering at a high temperature; d. and (3) cooking, sintering and flattening integrated sintering: in the sintering process, the highest sintering temperature range of the ceramic substrate is 1620-1700 ℃, the high-temperature heat preservation time range is 4-5h, and after sintering and cooling, the tungsten-molybdenum plate and the ceramic substrate are respectively taken out to obtain a product.

Furthermore, in the step b, the thickness of the tungsten-molybdenum plate is 2-3 mm.

Furthermore, in the step b, the surface roughness of the tungsten-molybdenum plate ranges from Ra0.2 to 0.4 μm.

Furthermore, in the step b, the warping degree of the tungsten-molybdenum plate is less than or equal to 0.1 mm.

Furthermore, in the step b, when the thickness of the final product is within 0.5mm, the number of the ceramic substrates to be placed is not more than 5, that is, the number of the tungsten-molybdenum plates is not more than 6.

Furthermore, in the step b, when the thickness of the final product is within 0.5-1mm, the number of the ceramic substrates to be placed does not exceed 10, that is, the number of the tungsten-molybdenum plates does not exceed 11.

Further, in the step c, the gas in the reducing atmosphere is a mixed gas of hydrogen and nitrogen and hydrogen.

Furthermore, in step c, the atmosphere in the protective atmosphere is nitrogen or other inert gases.

Furthermore, in the step c, the fluctuation range of the temperature difference interval of the kiln in the high-temperature sintering state is within 30 ℃.

The invention has the beneficial effects that: after the sintering, the warping degree of the product can be directly within 0.05mm, the ceramic volume density is not reduced by the influence of pressure sintering, the surface roughness of the substrate after sintering can be directly below 0.1 mu m, the overall product performance is excellent, and the requirement of a high-end ceramic substrate is met.

The invention successfully combines the two working procedures of the conventional ceramic substrate baking and flattening into one sintering working procedure. The energy conservation and emission reduction in the production process are realized, the production and manufacturing period is shortened, and the high-quality and high-efficiency manufacturing process of the ceramic substrate is realized. The invention is especially suitable for the integral sintering process of the electronic ceramic substrate.

Detailed Description

The integral sintering method of the electronic ceramic substrate comprises the following steps: a. glue removing and degreasing treatment of the ceramic substrate blank: placing the formed ceramic substrate into a glue discharging and degreasing kiln, and performing glue discharging and degreasing treatment on the ceramic substrate, wherein the glue discharging, degreasing and sintering temperature range is 1300-1400 ℃; B. arranging a ceramic substrate sandwiched between tungsten and molybdenum sheets: the sintering kiln tool adopts a high-temperature tungsten-molybdenum plate, wherein the size of the tungsten-molybdenum plate is slightly larger than that of the ceramic substrate, the green body single piece after the ceramic substrate is subjected to glue removal and degreasing is placed on the tungsten-molybdenum plate, a layer of tungsten-molybdenum plate is covered on the ceramic substrate, the next ceramic substrate is placed on the previous tungsten-molybdenum plate, and the operation is repeated and circulated in sequence, wherein the number of stacked layers ensures that the ceramic substrate at the bottommost part cannot be crushed; C. sintering in a reducing atmosphere furnace: putting the well placed kiln furniture and the sintered whole body of the ceramic into a kiln with a reducing atmosphere or a protective atmosphere for sintering at a high temperature; D. and (3) cooking, sintering and flattening integrated sintering: in the sintering process, the highest sintering temperature range of the ceramic substrate is 1620-1700 ℃, the high-temperature heat preservation time range is 4-5h, and after sintering and cooling, the tungsten-molybdenum plate and the ceramic substrate are respectively taken out to obtain a product.

The ceramic substrate sintered by the method provided by the invention can realize the integrated sintering of the substrate sintering and flattening, not only saves energy and reduces emission in the production process, but also shortens the production and manufacturing period, and realizes the high-quality and high-efficiency manufacturing process of the ceramic substrate

In order to achieve more precise sintering control and thus better product quality, the tungsten molybdenum plate is defined as follows, preferably as follows: in the step b, the thickness of the tungsten-molybdenum plate is 2-3 mm; preferably, in the step b, the surface roughness range of the tungsten-molybdenum plate is Ra0.2-0.4 μm; in the step b, the warping degree of the tungsten-molybdenum plate is less than or equal to 0.1 mm.

In the actual manufacturing process, the number of the ceramic substrates to be placed is limited according to the requirements of the final product, so that the bottommost ceramic substrate cannot be crushed, and in the step b, preferably, when the thickness of the final product is within 0.5mm, the number of the ceramic substrates to be placed does not exceed 5, that is, the number of the tungsten-molybdenum plates does not exceed 6. Preferably, in the step b, when the thickness of the final product is within 0.5-1mm, the number of the ceramic substrates to be placed is not more than 10, that is, the number of the tungsten-molybdenum plates is not more than 11.

In order to obtain a better reducing atmosphere, it is preferable that in step c, the gas in the reducing atmosphere is a mixed gas of hydrogen and nitrogen and hydrogen. In order to obtain a better protective atmosphere, in step c, the gas in the protective atmosphere is nitrogen and other inert gases. In order to ensure the stability of temperature fluctuation of the kiln during high-temperature sintering so as to ensure the product quality, in the step c, the fluctuation range of the temperature difference interval of the kiln in a high-temperature sintering state is preferably within 30 ℃.

Examples

Example 1

The 99.6 percent alumina ceramic substrate is molded by adopting a dry pressing molding mode. The specification of the formed green body is 62mm 1mm, the green body is subjected to binder removal and degreasing in a kiln with an oxidizing atmosphere, the highest temperature of the binder removal and degreasing is 1350 ℃, the green body subjected to binder removal is subjected to interlapping by using a high-temperature molybdenum plate with the thickness of 65mm 2.5mm, the green body is placed in a mode of clamping 10 ceramic substrate green bodies by using 11 high-temperature molybdenum plates, after the placement of the green body is finished, the molybdenum plate and the sintered whole green body are placed in a kiln with a reducing atmosphere, the sintering atmosphere is nitrogen-hydrogen mixed gas, and nitrogen gas: the hydrogen molar ratio is 1:3, the sintering highest temperature is 1620 ℃, the heat preservation time is 4h, the product is marked as C1 after sintering, the volume density, the warping degree and the surface roughness of C1 are tested, and the test results are shown in Table 1.

Example 2

And forming the 99.6 percent alumina ceramic substrate by adopting a tape casting mode. Forming a green body with the specification of 62mm 0.47mm, carrying out binder removal and degreasing on the green body in a kiln with an oxidizing atmosphere, carrying out binder removal and degreasing at the highest temperature of 1300 ℃ on the green body, sandwiching the binder removed green body by using a high-temperature molybdenum plate with the thickness of 65mm 2.5mm, carrying out blank arranging in a manner that 5 ceramic substrate blanks are sandwiched by 6 high-temperature tungsten plates, placing the sintered whole of the tungsten plate and the green body in the kiln with the nitrogen atmosphere after the blank arranging is finished, wherein the purity of the nitrogen is 99.9%, the sintering highest temperature is 1620 ℃, and the heat preservation time is 4h, marking the product as C2 after sintering, and testing the volume density, warping degree and surface roughness of C2, wherein the test results are shown in Table 1.

Example 3

And forming the 99% beryllium oxide ceramic substrate in a dry pressing forming mode. The specification of the formed green body is 62mm 1mm, the green body is subjected to binder removal and degreasing in a kiln with an oxidizing atmosphere, the highest binder removal and degreasing temperature is 1400 ℃, the green body subjected to binder removal is subjected to interlapping by using a high-temperature molybdenum plate with 65mm 2.5mm, the blank is placed in a mode that 10 ceramic substrate blanks are clamped by 11 high-temperature tungsten plates, after the blank is placed, the whole sintering of the tungsten plate and the blank is placed in a reducing atmosphere kiln, the sintering atmosphere is nitrogen-hydrogen mixed gas, wherein nitrogen gas: the hydrogen molar ratio is 1:3, the sintering maximum temperature is 1700 ℃, the heat preservation time is 5h, the product is marked as C3 after sintering, the volume density, the warping degree and the surface roughness of C3 are tested, and the test results are shown in Table 1.

TABLE 1

The experimental data can show that the warping degree of the ceramic substrate can be within 0.05mm directly, the ceramic volume density is not reduced due to the influence of compression sintering, the surface roughness of the sintered substrate can be below 0.1 mu m directly, the overall product performance is excellent, the requirements of high-end ceramic substrates are met, the technical advantages are obvious, and the market popularization prospect is wide.