Loading and placing device and method for preparing large-size high-precision ceramic polishing disc
By using a device with hollow spheres covered between the disk-shaped sintering plate and the pad during the large-size ceramic sintering process, the warping and deformation problem is solved, and the sintering of high-precision ceramic discs is achieved, ensuring the flatness and performance of the product Uniformity reduces manufacturing costs.
Patent Information
- Application Number
- CN202411016629.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-29
- Publication Date
- 2024-12-10
AI Technical Summary
During the preparation of large-size ceramics, warping and deformation are prone to occur, resulting in a decline in product performance. In addition, traditional methods increase thickness or use high-temperature corundum sand carriers will increase manufacturing cost and affect performance.
The disc-shaped fire plate and pad plate are used to cover the hollow spheres, and the spheres are fixed by high-temperature corundum sand rings to ensure that the spheres are placed in a horizontal state to reduce the tensile stress during sintering and shrinking, and promote the gap between the spheres. Hot air flow exchange to alleviate shrinkage deformation.
It effectively avoids warping and deformation, improves the flatness and performance uniformity of ceramic discs, reduces manufacturing costs, and ensures high precision and stability of the product.
Smart Images
Figure CN119099020A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of electrostatic chucks, and in particular to a mounting device and method for preparing large-size high-precision ceramic polishing discs. Background Art
[0002] With the localization of semiconductor component manufacturing processes, large-size ceramic green body preparation can completely replace foreign products to achieve independent research and development and manufacturing. In the process of structural parts preparation, forming is generally achieved by dry pressing and isostatic pressing. After forming, the green body has a certain strength and uniformity, which is conducive to obtaining a ceramic sintered body with stable performance and uniform crystal phase. In the process of ceramic sintering, the loading process and sintering process are the key to preparation. If the loading process is unreasonable, it is difficult to obtain a product with good performance even with a mature sintering curve. Especially for high-precision and large-size products, the defects produced need to be compensated by heat treatment, and the green body performance (mechanical properties and electrical properties) after heat treatment will be reduced by an order of magnitude. Or it can be achieved by increasing the thickness of the green body. Increasing the thickness will undoubtedly increase the manufacturing cost and have a certain impact on the product performance. For the sintering of ceramic parts within general size (300mm), high-temperature corundum sand is used as a carrier. The high-temperature corundum sand that has been leveled by horizontal measurement is placed on the ceramic green body for sintering. Due to the light weight of the green body, the performance of the product after sintering meets the process requirements after testing. However, when preparing and sintering large-size structural parts (φ650mm or larger), warping and deformation will occur when sintering in the same way. Summary of the invention
[0003] The technical problem to be solved by the present invention is to provide a device and method for preparing large-sized high-precision ceramic polishing disks, so as to solve the problems raised in the background technology and avoid warping and deformation during sintering of large-sized ceramics.
[0004] In order to solve the above technical problems, the technical solution of the present invention is:
[0005] On the one hand, the present invention provides a loading device for preparing large-size high-precision ceramic polishing discs, the loading device comprising a disc-shaped supporting plate, a disc-shaped padding plate being provided on the supporting plate, the diameter of the disc-shaped padding plate being smaller than the diameter of the disc-shaped supporting plate, a plurality of first spheres being evenly spread between the padding plate and the supporting plate, any one of the first spheres having a certain gap with other adjacent first spheres, the first spheres being hollow spheres, a plurality of second spheres being evenly spread above the padding plate, any one of the second spheres having a certain gap with other adjacent second spheres, the second spheres being hollow spheres, the plurality of second spheres being used for placing disc-shaped ceramic discs to be sintered, the diameter of the disc-shaped ceramic discs to be sintered being smaller than the diameter of the padding plate.
[0006] Preferably, the area covered with several of the first spheres is larger than the area of the pad, the area covered with several of the first spheres is smaller than the area of the supporting plate, the area covered with several of the second spheres is smaller than the area of the pad, and the area covered with several of the second spheres is larger than the area of the disc-shaped ceramic disk to be sintered.
[0007] Preferably, a circle of first high-temperature corundum sand is arranged at the edge of the first sphere that is covered with sand, and a circle of second high-temperature corundum sand is arranged at the edge of the second sphere that is covered with sand.
[0008] Preferably, the material of the backing plate is the same as the material of the disc-shaped ceramic disc to be sintered.
[0009] Preferably, the disc-shaped ceramic disk to be sintered is an alumina ceramic disk.
[0010] Preferably, the first sphere and the second sphere are both high-temperature alumina hollow spheres.
[0011] Preferably, the diameters of the first sphere and the second sphere are both 3 μm to 5 μm.
[0012] Preferably, the diameter of the disc-shaped ceramic disc to be sintered is greater than or equal to 650 mm, and the thickness is greater than or equal to 35 mm.
[0013] Another aspect of the present invention discloses a method for using the above-mentioned device for preparing a large-size high-precision ceramic polishing disc, characterized in that the method comprises the following steps:
[0014] Sprinkle a circle of first high-temperature corundum sand on the outer periphery of the firing plate, and pile it up to a certain height with tools. Place the first hollow sphere within the first high-temperature corundum sand circle, and place the first machined ceramic pad on the firing plate adjusted to a horizontal state, and adjust the spacing in the furnace;
[0015] Sprinkle a circle of second high-temperature corundum sand around the gasket, and use tools to pile up the second high-temperature corundum sand circle to a certain height to prevent the hollow second ball from overflowing and leaking;
[0016] Place the second hollow sphere in the space of the second high-temperature corundum sand circle, rotate it with a water plate to make the hollow sphere fully fill the space, and then use a level to adjust its level in different directions to make it all in a horizontal state;
[0017] The machined disc-shaped ceramic disc to be sintered is slowly placed on the adjusted gasket and properly adjusted;
[0018] The kiln car slowly rises into the furnace and sintering is carried out according to the same curve. After the temperature drops, the flatness and appearance of the green body are measured.
[0019] The above technical solution has the following beneficial effects:
[0020] The carrier does not contaminate the product;
[0021] The point contact between the hollow ball and the green body can reduce the tensile stress during sintering shrinkage, and the gap between the balls is conducive to the heat exchange of the hot air flow to ensure uniform product performance;
[0022] The added gaskets can alleviate shrinkage deformation. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 The present invention is a schematic structural diagram of a device for preparing large-size and high-precision ceramic polishing discs. DETAILED DESCRIPTION
[0024] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0025] Example 1
[0026] A device for preparing a large-size high-precision ceramic polishing disc, comprising a disc-shaped support plate 1, a disc-shaped pad 4 is arranged on the support plate 1, the diameter of the disc-shaped pad 4 is smaller than the diameter of the disc-shaped support plate 1, a plurality of first spheres 2 are evenly spread between the pad 4 and the support plate 1, any one of the first spheres 2 has a certain gap with other adjacent first spheres 2, the first spheres 2 are hollow spheres, the weight of the hollow spheres is lighter, and the manufacturing material can be saved, a plurality of second spheres 5 are evenly spread above the pad 4, any one of the second spheres 5 has a certain gap with other adjacent second spheres 5, the second spheres 5 are hollow spheres, and disc-shaped ceramic discs 7 to be sintered are placed on the plurality of second spheres 5, and the diameter of the disc-shaped ceramic discs 7 to be sintered is smaller than the diameter of the pad 4;
[0027] The disc-shaped pad 4 is placed on the setter 1, and a plurality of first spheres 2 are evenly spread between the pad 4 and the setter 1. The diameter of the disc-shaped pad 4 is smaller than the diameter of the disc-shaped setter 1, so that the disc-shaped pad 4 is conveniently placed. The pad 4 can alleviate shrinkage deformation.
[0028] The contact between the points of the second sphere 5 and the disc-shaped ceramic disk 7 to be sintered can reduce the tensile stress during sintering shrinkage. The gap between the spheres is conducive to the heat exchange of the hot air flow to ensure uniform product performance and improve the sintering efficiency. Since the disc-shaped ceramic disk 7 to be sintered is in contact with the surface of the second sphere 5, the thermal expansion and contraction generated during the sintering process will cause the second sphere 5 to move some positions, and it is not easy to cause the disc-shaped ceramic disk 7 to be sintered to be broken due to the thermal expansion and contraction during the sintering process.
[0029] The area covered with a plurality of the first spheres 2 is larger than the area of the backing plate 4, the area covered with a plurality of the first spheres 2 is smaller than the area of the setting plate 1, the area covered with a plurality of the second spheres 5 is smaller than the area of the backing plate 4, and the area covered with a plurality of the second spheres 5 is larger than the area of the disc-shaped ceramic plate 7 to be sintered, so as to facilitate the placement of the backing plate 4 and the disc-shaped ceramic plate 7 to be sintered;
[0030] A first high-temperature corundum sand circle 3 is arranged at the edge of the first sphere 2, and a second high-temperature corundum sand circle 6 is arranged at the edge of the second sphere 5. The first high-temperature corundum sand circle 3 can limit the position of the first sphere 2 to prevent the first sphere 2 from running around and keep the approximate position of the first sphere 2. The second high-temperature corundum sand circle 6 can limit the position of the second sphere 5 to prevent the second sphere 5 from running around and keep the approximate position of the second sphere 5.
[0031] The material of the backing plate 4 is the same as that of the disc-shaped ceramic plate 7 to be sintered, so as to prevent the backing plate 4 from contaminating the disc-shaped ceramic plate 7 during the sintering process;
[0032] The disc-shaped ceramic disk 7 to be sintered is an alumina ceramic disk. In other implementations of this embodiment, the disc-shaped ceramic disk 7 to be sintered may be an aluminum nitride ceramic disk, or other types of ceramics;
[0033] The first sphere 2 and the second sphere 5 are both high-temperature alumina hollow spheres. The materials of the first sphere 2 and the second sphere 5 can be selected according to the material of the disc-shaped ceramic disc 7 to be sintered, and can be the same as the material of the disc-shaped ceramic disc 7 to be sintered; the diameters of the first sphere 2 and the second sphere 5 are both 3 μm to 5 μm, preferably 4 μm;
[0034] The diameter of the disc-shaped ceramic disk 7 to be sintered is 650mm and the thickness is 35mm. For ceramic disks of general size, i.e., with a diameter within 300mm, high-temperature corundum sand is used as a carrier. The high-temperature corundum sand that has been leveled by horizontal measurement is placed on the ceramic green body for sintering. Since the green body is light in weight, the performance of the product after sintering meets the process requirements after testing. For ceramic disks with a diameter of 650mm and a thickness of 35mm, the loading device in this application is used for placement and sintering into ceramic disks, which can meet the needs. In other implementations of this embodiment, the diameter of the disc-shaped ceramic disk 7 can be greater than 650mm and the thickness can be greater than 35mm.
[0035] Example 2
[0036] A method for using the above-mentioned device for preparing a large-size high-precision ceramic polishing disc is characterized by comprising the following steps:
[0037] Sprinkle a circle of first high-temperature corundum sand 3 around the outer periphery of the setting plate 1, and pile it up to a certain height with tools, and place the first hollow sphere 2 within the range of the first high-temperature corundum sand circle 3, and first place the machined ceramic pad 4 on the setting plate 1 in a horizontal state, and adjust the spacing in the furnace;
[0038] Sprinkle a circle of second high-temperature corundum sand ring 6 on the outer periphery of the gasket, and use tools to pile up the second high-temperature corundum sand ring 6 to a certain height to prevent the hollow second ball from overflowing and leaking;
[0039] Place the hollow second sphere 5 in the space of the second high-temperature corundum sand circle 6, rotate it with a water plate to make the hollow sphere fully fill the space, and then use a level to adjust its level in different directions so that it is in a horizontal state;
[0040] The machined disc-shaped ceramic disc 7 to be sintered is slowly placed on the adjusted gasket and properly adjusted;
[0041] The kiln car slowly rises into the furnace and sintering is carried out according to the same curve. After the temperature drops, the flatness and appearance of the green body are measured.
[0042] The preparation process of large-size high-precision ceramic parts requires that each process section should try not to have or avoid process defects as much as possible, or the defects should be compensated in the next process. The defects caused by the sintering of the ceramic disc body are due to the irregular selection of the supporting auxiliary material particles, and the natural accumulation and filling of the particles with each other have a bridging phenomenon. During the sintering process, the body shrinks and moves due to the increase in temperature, and the bridges between the supporting particles will be destroyed as the temperature increases and the gravity of the body causes the body to deform. Although the bridge phenomenon is destroyed by the vibrated supporting material, the displacement of the supporting material with the shrinkage displacement of the body during sintering is very small or there is no displacement, which will generate tensile stress. When the stress exceeds the ultimate strength of the body, cracking occurs.
[0043] The customized high-temperature alumina hollow balls have high hardness, high purity, good sphericity, light weight and regular particle size. During sintering, the green body shrinks and the hollow balls move slightly with the shrinkage, which relieves the shrinkage resistance and avoids the tensile stress caused by unevenness. The evenly distributed and flat arrangement can realize the exchange of hot air flow between the balls, reduce the temperature gradient, and obtain a sintered body with consistent performance. According to the size and weight of the green body, alumina hollow balls with a diameter of 4μm are selected for sintering tests. Without changing the sintering system, green bodies of the same size are tested. After sintering, the green body is tested to have good flatness within the tolerance range, uniform shrinkage, no warping, deformation, and color difference, which fully meets the process requirements.
[0044] The above method can be used to sinter a ceramic disc blank with a diameter of 650 mm and a thickness of 35 mm, and the sintered product meets the requirements.
[0045] Since the support is made of the same material as the disc-shaped ceramic disc 7 to be sintered, there is no contamination to the disc-shaped ceramic disc 7 to be sintered;
[0046] The point contact between the hollow ball and the green body can reduce the tensile stress during sintering shrinkage, and the gap between the balls is conducive to the heat exchange of the hot air flow to ensure uniform product performance;
[0047] The added gaskets can alleviate shrinkage deformation.
[0048] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the scope of protection of the present invention.
Claims
1. A device for preparing large-size high-precision ceramic polishing discs, characterized in that: The loading device includes a disc-shaped firing plate, on which a disc-shaped pad is provided, the diameter of the disc-shaped pad is smaller than the diameter of the disc-shaped firing plate, a plurality of first spheres are evenly spread between the pad and the firing plate, any one of the first spheres has a certain gap with other adjacent first spheres, and the first spheres are hollow spheres, a plurality of second spheres are evenly spread above the pad, any one of the second spheres has a certain gap with other adjacent second spheres, and the second spheres are hollow spheres, and a plurality of second spheres are used to place disc-shaped ceramic disks to be sintered, and the diameter of the disc-shaped ceramic disks to be sintered is smaller than the diameter of the pad.
2. A device for preparing large-size high-precision ceramic polishing discs according to claim 1, characterized in that: The area of the region covered with a plurality of the first spheres is larger than the area of the pad, the area of the region covered with a plurality of the first spheres is smaller than the area of the supporting plate, the area of the region covered with a plurality of the second spheres is smaller than the area of the pad, and the area of the region covered with a plurality of the second spheres is larger than the area of the disc-shaped ceramic disk to be sintered.
3. The device for preparing large-size high-precision ceramic polishing discs according to claim 2 is characterized in that: A circle of first high-temperature corundum sand is arranged at the edge of the first sphere that is fully covered, and a circle of second high-temperature corundum sand is arranged at the edge of the second sphere that is fully covered.
4. The device for preparing large-size high-precision ceramic polishing discs according to claim 1, characterized in that: The material of the backing plate is the same as the material of the disc-shaped ceramic disc to be sintered.
5. The device for preparing large-size high-precision ceramic polishing discs according to claim 1, characterized in that: The disc-shaped ceramic disk to be sintered is an alumina ceramic disk.
6. A device for preparing large-size high-precision ceramic polishing discs according to claim 5, characterized in that: The first sphere and the second sphere are both high-temperature alumina hollow spheres.
7. A device for preparing large-size high-precision ceramic polishing discs according to claim 6, characterized in that: The diameters of the first sphere and the second sphere are both 3 μm to 5 μm.
8. The device for preparing large-size high-precision ceramic polishing discs according to claim 1, characterized in that: The diameter of the disc-shaped ceramic disc to be sintered is greater than or equal to 650 mm, and the thickness is greater than or equal to 35 mm.
9. A method for preparing a large-size high-precision ceramic polishing disc loading device using the device as claimed in claims 1 to 8, characterized in that: The method comprises the following steps: Sprinkle a circle of first high-temperature corundum sand on the outer periphery of the firing plate, and pile it up to a certain height with tools. Place the first hollow sphere within the first high-temperature corundum sand circle, and place the first machined ceramic pad on the firing plate adjusted to a horizontal state, and adjust the spacing in the furnace; Sprinkle a circle of second high-temperature corundum sand around the gasket, and use tools to pile up the second high-temperature corundum sand circle to a certain height to prevent the hollow second ball from overflowing and leaking; Place the second hollow sphere in the space of the second high-temperature corundum sand circle, rotate it with a water plate to make the hollow sphere fully fill the space, and then use a level to adjust its level in different directions to make it all in a horizontal state; The machined disc-shaped ceramic disc to be sintered is slowly placed on the adjusted gasket and properly adjusted; The kiln car slowly rises into the furnace and sintering is carried out according to the same curve. After the temperature drops, the flatness and appearance of the green body are measured.