Aluminum nitride heater based on slurry synergistic heating structure design and slurry preparation method thereof

Abstract

The invention discloses an aluminum nitride heater designed based on a slurry synergistic heating structure and a slurry preparation method of the aluminum nitride heater, and relates to the technical field of aluminum nitride heaters, the heater comprises a base body, a kovar electrode, a heating circuit and a protrusion structure, the heating circuit and the kovar electrode are brazed through the base body through soldering paste, and the protrusion structure is arranged on the base body. A protruding structure is arranged on the side wall of the base body, the kovar electrode penetrates through the protruding structure, and a pin circuit is arranged in the protruding structure. Through the collaborative design of the low-square-resistance slurry and the protruding structures, the problem that a traditional aluminum nitride heater loses efficacy at a high temperature due to the limitation of the melting point of silver-copper-titanium brazing solder is effectively solved, and compared with the limitation that the traditional heater can only stably work within 450 DEG C for a long time, when the electrode temperature of the heater is 450 DEG C, the electrode temperature of the aluminum nitride heater is 450 DEG C; the heating temperature of the working face can be increased to 550 DEG C, long-term stable work at the temperature of 550 DEG C or above is successfully achieved, the application scene of the heater is greatly expanded, and the use requirement under the high-temperature working condition is met.

Description

Technical Field

[0001] This invention relates to the field of aluminum nitride heater technology, specifically to an aluminum nitride heater based on a slurry-assisted heating structure design and a slurry preparation method thereof. Background Technology

[0002] Currently, most brazing solders are silver-copper-titanium. Silver-copper-titanium can effectively bond ceramics with circuits and electrodes, ensuring that the heater can operate stably for a long time within 450℃ and meet the temperature uniformity requirements of the entire working surface, with normal requirements controlled within ±1%. However, due to the low melting point of silver, copper, and titanium, the heater can only operate at a temperature below 450°C for extended periods. If the operating temperature is too high, the brazing solder at the electrodes softens, causing the electrodes to detach and preventing further heating. Therefore, ensuring long-term operation above 550°C while maintaining temperature uniformity across the entire working surface is a technical challenge that is currently difficult to overcome.

[0003] Based on this, we now provide an aluminum nitride heater based on a slurry-coordinated heating structure design and a slurry preparation method, which can eliminate the drawbacks of existing heaters. Summary of the Invention

[0004] The purpose of this invention is to provide an aluminum nitride heater based on a slurry-coordinated heating structure design and a slurry preparation method thereof, so as to solve the problems in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: An aluminum nitride heater based on a slurry-coordinated heating structure design includes a substrate, a Kovar electrode, a heating circuit, and a raised structure. The heating circuit and the Kovar electrode are brazed together on the substrate using solder paste. The raised structure is provided on the sidewall of the substrate, and the Kovar electrode passes through the raised structure. A pin circuit is provided inside the raised structure, and the pin circuit is made of a low sheet resistance slurry.

[0006] Based on the above technical solutions, the present invention also provides the following optional technical solutions: In one alternative: the matrix material is aluminum nitride ceramic.

[0007] This invention also discloses a method for preparing low sheet resistance slurry, comprising the following steps: S1: Add metal powder and ceramic powder in a certain proportion, grind them to obtain a mixed powder, and then add anhydrous ethanol for wet grinding to obtain a mixture. S2: After drying the mixture obtained in step S1 in a water bath, add an appropriate amount of binder to obtain the base slurry. S3: Grind the base slurry again to obtain a low sheet resistance slurry.

[0008] In one alternative: the binder solvent accounts for 2-5% of the mass percentage of the low-resistivity slurry, the ceramic powder accounts for 1-5% of the mass percentage of the low-resistivity slurry, the metal powder accounts for 68-78% of the mass percentage of the electronic slurry, and the anhydrous ethanol accounts for 10-12% of the mass percentage of the low-resistivity slurry.

[0009] In one alternative: In step S2, the binder component is ethyl cellulose.

[0010] In one alternative: In step S1, the metal powder is tungsten powder.

[0011] In one alternative: In step S2, the water bath drying temperature is 80°C.

[0012] In one alternative: the wet grinding time in step S1 is two hours.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention effectively solves the high-temperature failure problem of traditional aluminum nitride heaters caused by the melting point limitation of silver-copper-titanium brazing solder through the synergistic design of low sheet resistance slurry and raised structure. Compared with the limitation of traditional heaters that can only operate stably for a long time within 450°C, this heater can increase the working surface heating temperature to 550°C when the electrode temperature is 450°C, successfully achieving long-term stable operation above 550°C, greatly expanding the application scenarios of the heater and meeting the needs of use under high-temperature conditions.

[0014] This invention, through the rational design of the raised structure and the performance adaptation of the low sheet resistance slurry, increases the heating temperature while ensuring that the temperature uniformity of the entire working surface is controlled within ±1%, which is consistent with the temperature uniformity standard of traditional heaters. This avoids local equipment damage or malfunction caused by uneven temperature distribution during high-temperature operation, and ensures the stable operation of the heater.

[0015] The synergistic effect of the raised structure and the low sheet resistance slurry of the present invention not only enhances the heat insulation effect and reduces heat loss at the electrode, but also reduces energy loss through the low resistance characteristics of the low sheet resistance slurry, so that the input heat energy can be applied to the working surface heating more efficiently. While increasing the heating temperature, it also optimizes the energy utilization efficiency, combining high temperature performance and energy saving advantages. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention.

[0017] Figure 2 This is a flowchart illustrating the preparation process of the low sheet resistance slurry of the present invention.

[0018] Figure labeling: 1. Substrate, 2. Kovar electrode, 3. Heating circuit, 4. Protruding structure. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0020] In one embodiment, such as Figures 1-2 As shown, an aluminum nitride heater based on a slurry-coordinated heating structure design includes a substrate 1, a Kovar electrode 2, a heating circuit 3, and a raised structure 4. The heating circuit 3 and the Kovar electrode 2 are brazed together with solder paste on the substrate 1. The raised structure 4 is provided on the side wall of the substrate 1. The Kovar electrode 2 passes through the raised structure 4. A pin circuit is provided inside the raised structure 4. The pin circuit is made of low sheet resistance slurry.

[0021] In one embodiment, the substrate 1 material is aluminum nitride ceramic.

[0022] A method for preparing a low sheet resistance slurry includes the following steps: S1: Add metal powder and ceramic powder in a certain proportion, grind them to obtain a mixed powder, and then add anhydrous ethanol for wet grinding to obtain a mixture. S2: After drying the mixture obtained in step S1 in a water bath, add an appropriate amount of binder to obtain the base slurry. S3: Grind the base slurry again to obtain a low sheet resistance slurry.

[0023] In one embodiment, the binder solvent accounts for 2-5% of the mass percentage of the low sheet resistance slurry, the ceramic powder accounts for 1-5% of the mass percentage of the low sheet resistance slurry, the metal powder accounts for 68-78% of the mass percentage of the electronic slurry, and the anhydrous ethanol accounts for 10-12% of the mass percentage of the low sheet resistance slurry.

[0024] In one embodiment, in step S2, the binder component is ethyl cellulose.

[0025] In one embodiment, in step S1, the metal powder is tungsten powder.

[0026] In one embodiment, in step S2, the water bath drying temperature is 80°C.

[0027] In one embodiment, the wet grinding time in step S1 is two hours.

[0028] Taking a 35*35*3mm heater as an example: Comparative Example 1: The substrate 1 does not have the protruding structure 4 added, and ordinary slurry is used near the electrode; The working surface heating temperature is 455℃ when the electrode temperature is 450℃, and the temperature uniformity of the entire working surface is ±4%. Example 1: The substrate 1 does not have the protrusion structure 4, and the paste for the pin circuit near the electrode is improved by using a low sheet resistance paste; The working surface heating temperature is 480℃ when the electrode temperature is 450℃, and the temperature uniformity of the entire working surface is ±4%. Conclusion: Although the insulation effect is improved, it also leads to a decrease in temperature uniformity; Example 2: Add protrusion structure 4, but do not adjust the slurry near the electrode, and use ordinary slurry; The working surface heating temperature is 460℃ when the electrode temperature is 450℃, and the temperature uniformity of the entire working surface is ±1%. Conclusion: Temperature uniformity is not affected; although the insulation effect will be improved, the improvement is not significant. Example 3: Add a raised structure 4 and improve the paste of the pin circuit near the electrode by using a low sheet resistance paste; The working surface heating temperature is 550℃ when the electrode temperature is 450℃, and the temperature uniformity of the entire working surface is ±1%. Conclusion: Temperature uniformity is unaffected and the insulation effect is increased and enhanced.

[0029] The results are shown in the table below:

[0030] Compared to the limitations of traditional heaters that can only operate stably at temperatures below 450°C for extended periods, this heater can raise the working surface heating temperature to 550°C when the electrode temperature is 450°C, successfully achieving long-term stable operation above 550°C. This significantly expands the application scenarios of the heater and meets the usage requirements under high-temperature conditions.

[0031] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An aluminum nitride heater based on a slurry-co-heating structure design, characterized in that, The device includes a substrate (1), a Kovar electrode (2), a heating circuit (3), and a raised structure (4). The heating circuit (3) and the Kovar electrode (2) are brazed together by solder paste on the substrate (1). The raised structure (4) is provided on the side wall of the substrate (1). The Kovar electrode (2) passes through the raised structure (4). A pin circuit is provided inside the raised structure (4). The pin circuit is made of low sheet resistance paste.

2. The aluminum nitride heater based on a slurry-co-heating structure design according to claim 1, characterized in that, The substrate (1) material is aluminum nitride ceramic.

3. A method for preparing the low sheet resistance slurry according to claim 1, characterized in that, Includes the following steps: S1: Add metal powder and ceramic powder in a certain proportion, grind them to obtain a mixed powder, and then add anhydrous ethanol for wet grinding to obtain a mixture. S2: After drying the mixture obtained in step S1 in a water bath, add an appropriate amount of binder to obtain the base slurry. S3: Grind the base slurry again to obtain a low sheet resistance slurry.

4. The method for preparing low sheet resistance slurry according to claim 3, characterized in that, The binder solvent accounts for 2-5% of the mass percentage of the low-resistivity slurry, the ceramic powder accounts for 1-5% of the mass percentage of the low-resistivity slurry, the metal powder accounts for 68-78% of the mass percentage of the electronic slurry, and the anhydrous ethanol accounts for 10-12% of the mass percentage of the low-resistivity slurry.

5. The method for preparing low sheet resistance slurry according to claim 3, characterized in that, In step S2, the binder component is ethyl cellulose.

6. The method for preparing low sheet resistance slurry according to claim 3, characterized in that, In step S1, the metal powder is tungsten powder.

7. The method for preparing low sheet resistance slurry according to claim 3, characterized in that, In step S2, the water bath drying temperature is 80℃.

8. The method for preparing low sheet resistance slurry according to claim 3, characterized in that, The wet grinding time in step S1 is two hours.

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