Heat treatment process for aluminum nitride thin disc type products and blow-off crucible

Abstract

The invention discloses an aluminum nitride thin disc type product heat treatment process and a blow-off crucible, and the heat treatment process comprises the following steps: step 1, selecting an annealing crucible matched with the flatness of a product, and the flatness of the annealing crucible is not greater than 0.04 mm; 2, the positions of the annealing crucible and the product in the step 1 are adjusted, so that the annealing crucible and the product are combined; 3, the placing position of the annealing crucible in the annealing furnace is adjusted; 4, the temperature curve of the annealing furnace is controlled; and 5, the annealing crucible which is used for many times is subjected to flatness finishing. The annealing crucible comprises a crucible body, a containing cavity is formed in the crucible body, and the flatness of the bottom wall of the containing cavity is not larger than 0.04 mm. According to the method, the flatness of the aluminum nitride thin disc type product can be stably controlled, the efficiency and precision of heat treatment equipment can be effectively improved, and the high requirement of high-end manufacturing for the heat treatment equipment is met.

Description

Technical Field

[0001] The invention relates to the technical field of heat treatment, and in particular to a heat treatment process for aluminum nitride thin disk products and an annealing crucible. Background Art

[0002] In the field of heat treatment equipment, ceramic materials and mechanical processing, heat treatment of aluminum nitride thin disc products is a key process. Aluminum nitride is a high-performance ceramic material with excellent thermal conductivity, electrical conductivity, mechanical strength and chemical stability. Therefore, aluminum nitride thin disc products are widely used in electronics, electricity, machinery and aerospace. However, during the heat treatment process, aluminum nitride thin disc products are prone to unstable flatness, which will have an adverse effect on the performance and service life of the product.

[0003] In the related art, an annealing crucible is usually used to heat treat aluminum nitride thin disc products. An annealing crucible is a container used in the annealing process, usually made of graphite or ceramic materials. By placing the aluminum nitride thin disc products in the annealing crucible and then heating them in an annealing furnace, the aluminum nitride thin disc products can reach a uniform temperature, thereby eliminating internal stress and improving the flatness and dimensional stability of the products.

[0004] When the flatness of the annealing crucible does not match the flatness of the aluminum nitride thin disc product, it may cause the flatness of the product to be unstable during the heat treatment process, thereby affecting the final quality of the aluminum nitride thin disc product. Summary of the invention

[0005] The purpose of the present invention is to solve the above problems and provide a heat treatment process and annealing crucible for aluminum nitride thin disc products.

[0006] In order to achieve the above-mentioned purpose, the present invention specifically adopts the following technical solutions:

[0007] A heat treatment process for aluminum nitride thin disc products, comprising:

[0008] Step 1: Select an annealing crucible that matches the flatness of the product, and the flatness of the annealing crucible is not greater than 0.04 mm;

[0009] Step 2: adjusting the positions of the annealing crucible and the product in step 1 so that the two are combined;

[0010] Step 3: adjusting the placement position of the annealing crucible in the annealing furnace;

[0011] Step 4: Control the temperature curve of the annealing furnace;

[0012] Step 5: performing flatness trimming on the annealing crucible that has been used multiple times.

[0013] As a further description of the above technical solution, in step three, the annealing crucible is arranged in the middle of the annealing furnace.

[0014] As a further description of the above technical solution, in step 4, the temperature curve includes a heating curve, a heat preservation time and a cooling curve;

[0015] The heating range of the heating curve is 30-120°C / h, the heat preservation time is 1-6h, and the cooling range of the cooling curve is 60-120°C / h.

[0016] As a further description of the above technical solution, in step 4, the method of controlling the temperature curve includes using pulse heating and pulse cooling to achieve precise control of the temperature in the annealing furnace.

[0017] As a further description of the above technical solution, in step one, the flatness of the inner bottom wall of the annealing crucible is 0.04 mm.

[0018] As a further description of the above technical solution, in step three, a plurality of groups of annealing crucibles and products are placed in the annealing furnace in a stacked manner;

[0019] Therein, the annealing crucible for the product with a lower flatness value is arranged at the bottom of the combination.

[0020] As a further description of the above technical solution, in step four, the insulation temperature of the annealing furnace is not higher than 1600°C.

[0021] As a further description of the above technical solution, in step four, the heating rate of the annealing furnace is no more than 80° C. / h.

[0022] An annealing crucible, which is used in the heat treatment process of aluminum nitride thin disk products described in any of the above items, comprises a crucible body, a containing cavity is opened inside the crucible body, and the flatness of the bottom wall of the containing cavity is not greater than 0.04mm.

[0023] As a further description of the above technical solution, the material of the annealing crucible is boron nitride, and the beneficial effects of the present invention are as follows:

[0024] 1. The present invention can stably control the flatness of aluminum nitride thin disc products by designing an annealing crucible with better flatness, adjusting the combination of products with different flatness and crucibles, and the placement position in the annealing furnace, thereby effectively improving the efficiency and accuracy of heat treatment equipment and meeting the high requirements of high-end manufacturing for heat treatment equipment.

[0025] 2. The present invention can effectively improve the flatness stability of aluminum nitride thin disk products, thereby improving their performance and service life, and meeting the market demand for high-performance ceramic materials.

[0026] In order to more clearly illustrate the structural features and functions of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic flow diagram of the heat treatment process of the present invention;

[0028] Figure 2 is a schematic diagram of a combination of multiple annealing crucibles of the present invention;

[0029] Figure 3 It is a structural schematic diagram of the annealing crucible of the present invention;

[0030] Figure 4 It is a schematic diagram of placing multiple groups of annealing crucibles in an annealing furnace according to the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0032] like Figure 1 As shown, in one embodiment, a heat treatment process for aluminum nitride thin disk products comprises the following specific steps:

[0033] Step 1: Select an annealing crucible that matches the flatness of the product (aluminum nitride thin disc), where the flatness of the annealing crucible is no more than 0.04mm to meet the flatness requirements of most aluminum nitride thin disc products. Aluminum nitride thin disc products are not limited to aluminum nitride ceramic substrates and aluminum nitride films. Aluminum nitride thin disc products have high thermal conductivity, good insulation properties and chemical stability, and are widely used in high-power semiconductor integrated circuits, thick film circuits and thin film devices.

[0034] The influence of annealing crucibles with different flatness on the flatness of thin disc products is shown in the following table:

[0035] Product Number 1 2 3 4 5 Annealing crucible flatness (mm) 0.015 0.025 0.035 0.045 0.055 Thin plate product flatness (mm) - front 0.030 0.030 0.030 0.030 0.030 Flatness of thin disc products (mm) - rear 0.027 0.038 0.040 0.048 0.065 Product flatness change value (mm) -0.003 +0.008 +0.010 +0.018 +0.035

[0036] From the above data, it can be seen that as the flatness of the annealing crucible increases, the flatness change value of the thin disc product with the same flatness after heat treatment will also increase. And when the flatness of the annealing crucible is greater than 0.045mm, the flatness change value of the product after heat treatment increases exponentially. In some embodiments, the flatness of the annealing crucible is maintained below 0.04mm.

[0037] Step 2: Adjust the position of the annealing crucible and the product in step 1 so that the two are combined. Specifically, according to the flatness of the aluminum nitride thin disc product, select a suitable annealing crucible, and combine the product and the annealing crucible, that is, place the flat surface of the aluminum nitride thin disc product on the flat surface of the annealing crucible to achieve the best flatness stability effect. It is understandable that when the non-flat surface of the aluminum oxide thin film product is placed on the flat surface of the annealing crucible, during the heating or annealing process, it will affect the heat treatment effect of the aluminum nitride thin disc product, and further affect the performance and service life of the product. In some embodiments, the flatness of the aluminum nitride thin disc product is 0.05 mm, and an annealing crucible with a bottom inner wall flatness of 0.03 mm is selected, and then the aluminum nitride thin disc product is combined with the annealing crucible;

[0038] Step 3: Optimize the placement of the annealing crucible in the annealing furnace. Figure 2 In some embodiments, a combination of multiple sets of annealing crucibles and products are placed in an annealing furnace in a stacked manner. In this embodiment, 7 layers of annealing crucibles are arranged from top to bottom. When the thin disk product is heat treated, the change in flatness will also be different at different placement positions. Figure 4 In the two groups of comparative experiments, annealing crucibles with a flatness of 0.02-0.03mm and aluminum nitride thin discs with a flatness of 0.03-0.05mm were uniformly selected for experimental analysis, with three products in each group. The results are shown in the following table:

[0039] 1 2 3 average 1 2 3 average C06 +0.005 +0.010 +0.019 +0.011 C03 +0.018 +0.005 +0.021 +0.015 C05 -0.008 +0.003 +0.007 +0.001 C06 +0.010 -0.010 +0.004 +0.001 C04 -0.015 -0.020 -0.006 -0.014 C05 -0.003 -0.015 -0.004 -0.007 C03 -0.005 -0.015 +0.002 -0.006 C04 +0.011 -0.005 +0.002 +0.003 C02 +0.028 +0.003 +0.031 +0.021 C02 +0.030 +0.011 +0.029 +0.023 C01 +0.053 +0.085 +0.046 +0.061 C01 +0.086 +0.023 +0.045 +0.051

[0040] Among them, different numbers represent different placement layers of annealing crucibles.

[0041] The above two groups of comparative experiments show that when the annealing crucible is placed in the middle of the annealing furnace, that is, on the third and fourth layers of the annealing furnace, the flatness change of the product after heat treatment is relatively small or the flatness change of the product shows a trend of improvement. When the annealing crucible is placed at the bottom, the deformation of the product after heat treatment is the largest, and generally exceeds 0.05mm. When in use, place products with lower initial flatness values ​​at the bottom of the combination. If the final flatness requirements of the product are high, the bottom position can be left empty.

[0042] Step 4, controlling the temperature curve of the annealing furnace, the temperature curve includes a heating curve, a holding time and a cooling curve, wherein the heating temperature is 30-120°C / h, the holding time is 1-6h, and the cooling rate is 60-120°C / h. At the same time, the temperature curve is controlled by pulse heating or pulse cooling to achieve precise control of the temperature in the annealing furnace.

[0043] The following table shows the deformation of thin disc products after heat treatment at different heating rates, which is described in conjunction with specific embodiments:

[0044]

[0045] When the heating rate is slow, the flatness change of the product after heat treatment is small; when the heating rate is close to the upper limit of the range, the change in flatness after heat treatment increases significantly.

[0046]

[0047]

[0048] When the maximum temperature during insulation changes, the impact on the flatness of the thin disc product is shown in the table above. When the maximum temperature is ≤1600℃, the change in flatness is relatively small; when the maximum temperature is too high, the deformation increases sharply.

[0049] In summary, when the heating rate or holding temperature is too high, the flatness change of the thin disc product after heat treatment will increase, that is, the flatness of the thin disc product will deteriorate, while the holding time and cooling rate have little effect on the flatness of the product after heat treatment.

[0050] Step 5: Regularly and maintain the annealing crucible, and regularly check the status of the annealing crucible, and perform maintenance and replacement to ensure that its flatness is stably controlled. In some embodiments, the annealing crucible can be checked once a month. When it is found that the flatness exceeds 0.04 mm, it is necessary to trim the flatness in time to ensure that the flatness of the annealing crucible can meet the use requirements during subsequent use.

[0051] Step 6: Establish a complete quality control system and strictly monitor and manage every link in the heat treatment process to ensure that the flatness of the product is controlled.

[0052] In summary, the above steps can achieve stable control of the flatness of aluminum nitride thin disc products during heat treatment, so as to improve the quality and performance of aluminum nitride thin disc products.

[0053] refer to Figure 3 The present application also discloses an annealing crucible, which is used in the above-mentioned heat treatment process of aluminum nitride thin disc products, and includes a crucible body 1, and a receiving cavity 2 is opened inside the crucible body 1. The flatness of the bottom wall 2 of the receiving cavity is not greater than 0.04mm, so as to reduce the flatness change of aluminum nitride thin film products during the heat treatment process, thereby improving the performance and stability of aluminum nitride thin film products.

[0054] Optionally, the material of the annealing crucible is boron nitride, which can be selected according to actual needs.

[0055] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A heat treatment process for aluminum nitride thin disc products, characterized in that: include: Step 1: Select an annealing crucible that matches the flatness of the product, and the flatness of the annealing crucible is not greater than 0.04 mm; Step 2: adjusting the positions of the annealing crucible and the product in step 1 so that the two are combined; Step 3: adjusting the placement position of the annealing crucible in the annealing furnace; Step 4: Control the temperature curve of the annealing furnace; Step 5: performing flatness trimming on the annealing crucible that has been used multiple times.

2. The heat treatment process for aluminum nitride thin disk products according to claim 1, characterized in that: In step three, the annealing crucible is arranged in the middle of the annealing furnace.

3. The heat treatment process for aluminum nitride thin disk products according to claim 1, characterized in that: In step 4, the temperature curve includes a heating curve, a heat preservation time and a cooling curve; The heating range of the heating curve is 30-120°C / h, the heat preservation time is 1-6h, and the cooling range of the cooling curve is 60-120°C / h.

4. The heat treatment process for aluminum nitride thin disk products according to claim 1, characterized in that: In step 4, the temperature curve is controlled by pulse heating and pulse cooling to achieve precise control of the temperature in the annealing furnace.

5. The heat treatment process for aluminum nitride thin disk products according to claim 1, characterized in that: In step 1, the flatness of the inner bottom wall of the annealing crucible is 0.04 mm.

6. The heat treatment process for aluminum nitride thin disk products according to claim 1, characterized in that: In step three, a plurality of sets of annealing crucibles and products are placed in the annealing furnace in a stacked manner; Therein, the annealing crucible for the product with a lower flatness value is arranged at the bottom of the combination.

7. The heat treatment process for aluminum nitride thin disk products according to claim 1, characterized in that: In step 4, the insulation temperature of the annealing furnace is not higher than 1600°C.

8. The heat treatment process for aluminum nitride thin disk products according to claim 1, characterized in that: In step 4, the heating rate of the annealing furnace is no more than 80° C. / h.

9. An annealing crucible, used in the heat treatment process of aluminum nitride thin disk products according to any one of claims 1 to 8, characterized in that: The crucible comprises a crucible body, wherein a containing cavity is provided inside the crucible body, and the flatness of the bottom wall of the containing cavity is not greater than 0.04 mm.

10. The annealing crucible according to claim 9, characterized in that: The material of the annealing crucible is boron nitride.

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