Graphite piece for silicon carbide epitaxy

Abstract

The utility model discloses a graphite piece for silicon carbide epitaxy, which comprises an upper half-moon seat, a lower half-moon seat and two connecting side parts respectively connected with two sides of the upper half-moon seat and the lower half-moon seat, and the upper half-moon seat, the lower half-moon seat and the connecting side parts are of an integrated structure. The upper half-moon seat comprises an upper arc-shaped part and an upper connecting plate connected with the two sides of the upper arc-shaped part, the lower half-moon seat comprises a lower arc-shaped part and a lower connecting plate connected with the two sides of the lower arc-shaped part, and the upper connecting plate, the lower connecting plate and the two connecting side parts form a reaction cavity. According to the utility model, through the arrangement of the graphite piece with the integrated structure, the difference during assembly is reduced, the identity of the structure of the graphite piece in the life cycle is ensured, and the badness caused by the assembly difference is reduced; and meanwhile, the graphite piece can be integrally detached for cleaning, so that the cleaning effect is ensured, the cleanliness of the reaction hearth after each maintenance is favorably improved, and the condition that the wafer has defects due to insufficient cleanliness of the hearth is reduced.

Description

Technical Field

[0001] The utility model relates to the field of silicon carbide epitaxial equipment, in particular to a graphite component for silicon carbide epitaxy. Background Art

[0002] In the existing horizontal gas flow type silicon carbide epitaxial equipment, the reaction zone of the furnace body is divided into two semi-circular graphite components, namely the upper semi-moon and the lower semi-moon. By installing a strip-shaped cuboid silicon carbide support block on both sides between the upper and lower semi-circular graphite components, a reaction cavity in the shape of a cylinder is formed.

[0003] The above-mentioned split structure has high requirements for the restoration and assembly of equipment maintenance personnel. It is relatively easy to have assembly differences between the upper semi-moon and the lower semi-moon, resulting in a lack of certain airtightness on the side of the furnace reaction zone or upstream of the air inlet, leading to air flow disorder and abnormal growth. In addition, when maintaining the graphite component with a split structure, the entire graphite component reaction zone cannot be removed as a whole. Only the upper semi-moon can be removed for cleaning. The removal of the lower semi-moon is relatively complicated, resulting in incomplete cleaning during the production cycle maintenance, which will cause many problems with the wafers produced after the furnace is maintained. Summary of the Invention

[0004] The purpose of the utility model is to provide a graphite component for silicon carbide epitaxy to solve the problems of inconvenient disassembly and assembly and incomplete maintenance of the existing upper semi-moon and lower semi-moon with a split structure.

[0005] To achieve the above purpose, a graphite component for silicon carbide epitaxy provided by the utility model includes an upper semi-moon seat, a lower semi-moon seat, and two connecting side parts respectively connecting the two sides of the upper semi-moon seat and the lower semi-moon seat. The upper semi-moon seat, the lower semi-moon seat, and the connecting side parts are of an integral structure. The upper semi-moon seat includes an upper arc part and upper connecting plates connecting both sides of the upper arc part. The lower semi-moon seat includes a lower arc part and lower connecting plates connecting both sides of the lower arc part. The upper connecting plates, the lower connecting plates, and the two connecting side parts form a reaction cavity.

[0006] Preferably, the upper semi-moon seat, the lower semi-moon seat, and the connecting side parts are integrally in an elliptical cylindrical shape, and the upper semi-moon seat and the lower semi-moon seat are symmetrically arranged.

[0007] Preferably, the thickness of the upper connecting plate is greater than the thickness of the upper arc part, and the thickness of the lower connecting plate is greater than the thickness of the lower arc part.

[0008] Preferably, the lower connecting plate has a first side facing the upper connecting plate. A circular groove is formed in the middle of the first side for setting a graphite tray, which is used to carry wafers. The lower connecting plate is also provided with ventilation holes that extend from one end of the lower connecting plate towards the circular groove and communicate with the graphite tray for suspending the wafers.

[0009] Preferably, the upper connecting plate is also provided with a temperature measuring hole that extends towards the middle of the upper connecting plate.

[0010] Preferably, the reaction chamber has an intake upstream end and an exhaust downstream end. The ventilation holes and the temperature measuring holes are both arranged near the intake upstream end.

[0011] Preferably, a first positioning strip and a second positioning strip are respectively arranged on both sides of the lower connecting plate. The first positioning strip is attached to the connecting side part close to it, and the second positioning strip is attached to the connecting side part close to it. There is a reserved distance between the two ends of the first positioning strip and the second positioning strip and the two end faces of the lower connecting plate respectively. A U-shaped protective part is also arranged in the reaction chamber. The U-shaped protective part includes a bottom plate and a first vertical plate and a second vertical plate respectively connected to both sides of the bottom plate. A first matching groove for cooperating with the first positioning strip is formed on the first vertical plate, and a second matching groove for cooperating with the second positioning strip is formed on the second vertical plate. The bottom plate is attached to the inner wall of the upper connecting plate, and the first vertical plate and the second vertical plate are respectively engaged with the first positioning strip and the second positioning strip and the first vertical plate and the second vertical plate are respectively attached to the corresponding connecting side parts.

[0012] Compared with the prior art, by setting the graphite part with an integrated structure, the present invention reduces the differences during assembly, ensures the identity of the structure of the graphite part during the life cycle, and reduces the defects caused by assembly differences; at the same time, the graphite part can be removed as a whole for cleaning, which ensures the cleaning effect, is beneficial to improving the cleanliness of the reaction furnace chamber after each maintenance, and reduces the situation that wafers have defects due to insufficient cleanliness of the furnace chamber. Description of the Drawings

[0013] Figure 1 It is a structural diagram of the graphite part for silicon carbide epitaxy of the present invention from one angle.

[0014] Figure 2 It is a structural diagram of the graphite part for silicon carbide epitaxy of the present invention from another angle.

[0015] Figure 3 is Figure 2 The cross-sectional view taken along line A-A in

[0016] Figure 4 isFigure 2 Cross-sectional view along line B-B in the middle.

[0017] Figure 5 It is a structural diagram of the U-shaped protective part in the present utility model. Specific embodiments

[0018] To describe in detail the technical content, structural features, and achieved effects of the present utility model, the following will be described in detail in conjunction with the embodiments and with reference to the accompanying drawings.

[0019] As Figures 1 to 4 As shown, an embodiment of the present utility model provides a graphite part 10 for silicon carbide epitaxy, which includes an upper semi-cylindrical seat 1, a lower semi-cylindrical seat 2, and two connecting side parts 3 respectively connecting the two sides of the upper semi-cylindrical seat 1 and the lower semi-cylindrical seat 2. The upper semi-cylindrical seat 1, the lower semi-cylindrical seat 2, and the connecting side parts 3 are of an integral structure. The upper semi-cylindrical seat 1 includes an upper arc portion 11 and upper connecting plates 12 connecting the two sides of the upper arc portion 11. The lower semi-cylindrical seat 2 includes a lower arc portion 21 and lower connecting plates 22 connecting the two sides of the lower arc portion 21. The upper connecting plates 12, the lower connecting plates 22, and the two connecting side parts 3 form a reaction chamber 4. Specifically, the upper semi-cylindrical seat 1, the lower semi-cylindrical seat 2, and the connecting side parts 3 are all made of graphite. A reaction chamber 4 is provided between the upper semi-cylindrical seat 1 and the lower semi-cylindrical seat 2. The reaction chamber 4 is used for wafer epitaxial growth. The reaction chamber 4 has a rectangular structure and is surrounded by the integral structure of the upper semi-cylindrical seat 1, the lower semi-cylindrical seat 2, and the connecting side parts 3. The structure is stable and will not cause problems of gas flow disorder due to assembly differences, facilitating the stable introduction of reaction gases and ensuring the effect of wafer epitaxial growth.

[0020] By setting the graphite part 10 of the integral structure in the embodiment of the present utility model, the differences during assembly are reduced, ensuring the identity of the structure of the graphite part 10 during the life cycle and reducing the defects caused by assembly differences. At the same time, the graphite part 10 can be taken out as a whole for cleaning, ensuring the cleaning effect, being beneficial to improving the cleanliness of the reaction furnace chamber after each maintenance, and reducing the situation where wafers have defects due to insufficient cleanliness of the furnace chamber.

[0021] In the embodiment of the present utility model, as Figure 1 As shown, the upper semi-cylindrical seat 1, the lower semi-cylindrical seat 2, and the connecting side parts 3 are integrally in an elliptical cylindrical shape, and the upper semi-cylindrical seat 1 and the lower semi-cylindrical seat 2 are symmetrically arranged. By designing the graphite part 10 into an elliptical cylindrical structure, it is ensured that the deformation of the graphite part 10 in a high-temperature environment is small, because the elliptical cylindrical design can enhance the overall structural strength of the graphite part 10, and there will be no deformation or cracking due to the wall thickness in some areas.

[0022] In the embodiment of the present utility model, as Figure 2As shown, the thickness of the upper connecting plate 12 is greater than that of the upper arc portion 11, and the thickness of the lower connecting plate 22 is greater than that of the lower arc portion 21. By setting the thicknesses of the upper connecting plate 12 and the lower connecting plate 22 to be relatively thick, the support strength of the graphite member 10 is further improved, and the design is ingenious.

[0023] In the embodiment of the present utility model, as Figures 1 to 4 shown, the lower connecting plate 22 has a first side surface 221 facing the upper connecting plate 12. A circular groove 5 is formed in the middle of the first side surface 221 for arranging a graphite tray, and the graphite tray is used for carrying wafers. An air vent 23 is also arranged on the lower connecting plate 22. The air vent 23 extends from one end of the lower connecting plate 22 towards the circular groove 5 and communicates with the graphite tray for suspending the wafers. Specifically, the wafers for epitaxy are first placed on the graphite tray, and gas is passed through the air vent 23 into the graphite tray to suspend the wafers.

[0024] In the embodiment of the present utility model, as Figures 1 to 3 shown, a temperature measuring hole 13 is also arranged on the upper connecting plate 12. The temperature measuring hole 13 extends towards the middle of the upper connecting plate 12, and the temperature measuring hole 13 is used for measuring the temperature of the graphite member 10.

[0025] Furthermore, the reaction chamber 4 has an intake upstream end 41 and an exhaust downstream end. Both the air vent 23 and the temperature measuring hole 13 are arranged close to the intake upstream end 41. Specifically, the intake upstream end 41 and the exhaust downstream end are arranged opposite to each other. By arranging both the air vent 23 and the temperature measuring hole 13 close to the intake upstream end 41, the structure is neater.

[0026] In the embodiment of the present utility model, as Figures 1 to 5As shown in the figure, the first positioning strip 61 and the second positioning strip 61 are respectively provided on both sides of the lower connecting plate 22. The first positioning strip 61 is attached to the connecting side part 3 close to it, and the second positioning strip 61 is attached to the connecting side part 3 close to it. There is a reserved distance between the two ends of the first positioning strip 61 and the second positioning strip 61 and the two end faces of the lower connecting plate 22 respectively. A U-shaped protective part 7 is also provided in the reaction chamber 4. The U-shaped protective part 7 includes a bottom plate 71 and a first vertical plate 72 and a second vertical plate 73 respectively connected to both sides of the bottom plate 71. A first matching groove 721 matching with the first positioning strip 61 is opened on the first vertical plate 72, and a second matching groove 731 matching with the second positioning strip 61 is opened on the second vertical plate 73. The bottom plate 71 is attached to the inner wall of the upper connecting plate 12. The first vertical plate 72 and the second vertical plate 73 are respectively engaged with the first positioning strip 61 and the second positioning strip 61, and the first vertical plate 72 and the second vertical plate 73 are respectively attached to the corresponding connecting side parts 3. Specifically, in order to prevent the reaction gas flow from depositing on the surfaces of the upper connecting plate 12 and the connecting side part 13, a U-shaped protective part 7 is placed in the reaction chamber 4 to separate the reaction gas flow from the upper connecting plate 12 and the connecting side part 13. During maintenance, only the U-shaped protective part 7 needs to be taken out and the deposits on its surface can be cleaned. The lengths of the first positioning strip 61 and the second positioning strip 61 are less than the length of the lower connecting plate 22 so that there is a reserved distance between the two ends of the first positioning strip 61 and the second positioning strip 61 and the two end faces of the lower connecting plate 22 respectively, which is convenient for the engagement connection with the first matching groove 721 and the second matching groove 731.

[0027] The above-disclosed are only the preferred examples of the present invention. Of course, the scope of rights of the present invention cannot be limited by this. Therefore, the equivalent changes made according to the scope of the patent application of the present invention still fall within the scope covered by the present invention.

Claims

1. A graphite part for silicon carbide epitaxy, characterized in that: It includes an upper semi-lunar seat, a lower semi-lunar seat and two connecting side portions respectively connected to the upper semi-lunar seat and the lower semi-lunar seat on both sides. The upper semi-lunar seat, the lower semi-lunar seat and the connecting side portions are an integrated structure. The upper semi-lunar seat includes an upper arc-shaped portion and an upper connecting plate connecting the two sides of the upper arc-shaped portion. The lower semi-lunar seat includes a lower arc-shaped portion and a lower connecting plate connecting the two sides of the lower arc-shaped portion. The upper connecting plate, the lower connecting plate and the two connecting side portions form a reaction chamber.

2. The graphite article for silicon carbide epitaxy according to claim 1, characterized in that: The upper half-moon seat, the lower half-moon seat and the connecting side portion are in an elliptical cylindrical shape as a whole, and the upper half-moon seat and the lower half-moon seat are symmetrically arranged.

3. The graphite article for silicon carbide epitaxy according to claim 1, characterized in that: The thickness of the upper connecting plate is greater than the thickness of the upper arc-shaped portion, and the thickness of the lower connecting plate is greater than the thickness of the lower arc-shaped portion.

4. The graphite article for silicon carbide epitaxy according to claim 1, characterized in that: The lower connecting plate has a first side surface facing the upper connecting plate, a circular groove is provided in the middle of the first side surface for arranging a graphite tray, and the graphite tray is used to carry the wafer. The lower connecting plate is also provided with an air vent, which extends from one end of the lower connecting plate toward the circular groove and is connected to the graphite tray for suspending the wafer.

5. The graphite article for silicon carbide epitaxy according to claim 4, characterized in that: The upper connecting plate is also provided with a temperature measuring hole, and the temperature measuring hole extends toward the middle of the upper connecting plate.

6. The graphite article for silicon carbide epitaxy according to claim 5, characterized in that: The reaction chamber has an air intake upstream end and an exhaust gas downstream end, and the air vent and the temperature measuring hole are both arranged close to the air intake upstream end.

7. The graphite article for silicon carbide epitaxy according to claim 1, characterized in that: The first and second positioning strips are respectively provided on both sides of the lower connecting plate, the first positioning strip is arranged in contact with the connecting side portion close to the first positioning strip, and the second positioning strip is arranged in contact with the connecting side portion close to the second positioning strip, and both ends of the first positioning strip and the second positioning strip have a reserved distance from the two end surfaces of the lower connecting plate respectively, and a U-shaped protective member is also provided in the reaction chamber, and the U-shaped protective member includes a bottom plate and a first vertical plate and a second vertical plate respectively connected to both sides of the bottom plate, a first matching groove matching with the first positioning strip is provided on the first vertical plate, and a second matching groove matching with the second positioning strip is provided on the second vertical plate, the bottom plate is fitted with the inner wall of the upper connecting plate, the first vertical plate and the second vertical plate are respectively engaged and connected with the first positioning strip and the second positioning strip, and the first vertical plate and the second vertical plate are respectively fitted with the corresponding connecting side portions.

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