Wafer boat

Abstract

The invention relates to a wafer boat. The wafer boat comprises a bottom plate, a top plate and a plurality of supporting columns located between the bottom plate and the top plate. Each supporting column is provided with a plurality of supporting parts, each supporting part is provided with a first sub-supporting part fixedly connected to the corresponding supporting column and a second sub-supporting part fixedly connected to the first sub-supporting part, and the second sub-supporting part is arranged at the end, away from the corresponding supporting column, of the first sub-supporting part. When the wafer is placed on the supporting surface of the second sub-supporting part, the thickness of the first sub-supporting part is larger than that of the second sub-supporting part, so that a step can be formed, and the height of the highest point in the second sub-supporting part is smaller than that of the first sub-supporting part, so that the contact area between the wafer and the wafer boat is small; according to the wafer boat, the transverse displacement of the wafer is reduced, the wafer is effectively prevented from sliding, the contact area of the wafer and the wafer boat is small, particles generated by friction between the wafer and the wafer boat can be reduced, and the cleanliness of the wafer is higher.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and particularly to a wafer boat. Background Art

[0002] In the semiconductor manufacturing process, high-temperature processes for wafers (such as oxidation, diffusion, annealing, etc.) are key steps in forming device structures. During this process, a wafer boat (Cassette), as the core tool for carrying wafers, needs to stably feed multiple wafers into a high-temperature furnace tube for heat treatment.

[0003] Traditional wafer boats are prone to thermal stress deformation at high temperatures, resulting in easy sliding or offset of wafers. In addition, the support structures of traditional wafer boats mostly adopt large-area flat or annular contact designs, and the effective contact area between the wafers and the support frames is relatively large. At high temperatures, due to thermal expansion or vibration, the wafers slide, and more friction particles are generated between the wafers and the support frames, affecting the wafer yield and making it difficult to meet the requirements of advanced processes for wafer cleanliness and process reliability. Summary of the Invention

[0004] In view of this, embodiments of this application provide a wafer boat. By arranging a plurality of support columns between the bottom plate and the top plate of the wafer boat, a plurality of support parts are respectively arranged on the same support column, a first sub-support part fixedly connected to the support column is respectively arranged on each support part, and a second sub-support part fixedly connected to the first sub-support part is arranged on each support part. The second sub-support part is arranged at one end of the first sub-support part away from the support column. When the wafer boat needs to carry wafers, the wafers are placed on the support surface of the second sub-support part. Since the thickness of the first sub-support part is greater than that of the second sub-support part, a step can be formed, and the height of the highest point in the second sub-support part is less than the height of the first sub-support part, so that the contact area between the wafers and the wafer boat is small. When the wafer boat expands due to heat, vibrates or deforms, the lateral displacement of the wafers is reduced, effectively preventing the wafers from sliding. And because the contact area between the wafers and the wafer boat is small, it helps to reduce the particulate matter generated by friction between the wafers and the wafer boat, making the wafer cleanliness higher.

[0005] In a first aspect, this application provides a wafer boat, including: A bottom plate, a top plate, and a plurality of support columns located between the bottom plate and the top plate; a plurality of support parts are respectively arranged on each support column, and there is a gap between two adjacent support parts on the same support column; Each support part respectively includes a first sub-support part and a second sub-support part. The first sub-support part is fixedly connected to the support column, the second sub-support part is fixedly connected to the first sub-support part, and is arranged at one end of the first sub-support part away from the support column. The thickness of the first sub-support part is greater than that of the second sub-support part to form a step, and the height of the highest point in the second sub-support part is less than the height of the first sub-support part. The highest point is used to support the wafers.

[0006] Since two adjacent supporting parts on the same supporting column are spaced by a specified distance, in other words, the multiple supporting parts on each supporting column are evenly distributed, which facilitates the batch placement of wafers and improves production efficiency.

[0007] A plurality of supporting parts are respectively arranged on a plurality of supporting columns of the susceptor. A first sub-supporting part fixedly connected to the supporting column is arranged on each supporting part, and a second sub-supporting part is arranged at one end of each supporting part away from the supporting column. When the susceptor carries a wafer, the wafer is placed on the second sub-supporting part. Since the thickness of the first sub-supporting part is greater than that of the second sub-supporting part, the first sub-supporting part and the second sub-supporting part can form a step, and the height of the highest point in the second sub-supporting part is less than the height of the first sub-supporting part, so that the contact area between the wafer and the supporting part is small. When the susceptor expands due to heat and vibrates or deforms, the lateral displacement of the wafer becomes smaller, and the wafer can be effectively prevented from sliding.

[0008] In a possible implementation of the first aspect, the surface of the first sub-supporting part on the side close to the central axis of the susceptor is a concave surface, the radius of curvature of the concave surface is 3 mm, and the thickness of the first sub-supporting part is 5 mm.

[0009] Since the surface shape of the first sub-supporting part on the side close to the center of the susceptor is concave in the direction away from the center of the susceptor, when the susceptor carries a wafer and the wafer is placed on the second supporting part, the wafer can abut against the concave surface of the first sub-supporting part, preventing the wafer from sliding and blocking the falling of friction particles, reducing wafer contamination.

[0010] In a possible implementation of the first aspect, the supporting surface of the second sub-supporting part facing the top plate is inclined towards the top plate, and the first angle between the supporting surface and the horizontal plane is an acute angle, and the horizontal plane is perpendicular to the extending direction of the supporting column.

[0011] In a possible implementation of the first aspect, the angle of the first angle is from 10 degrees to 30 degrees. In other words, the supporting surface of the second sub-supporting part is inclined relative to the horizontal plane. When the susceptor carries a wafer and the wafer is placed on the supporting surface of the second sub-supporting part, since the supporting surface of the second sub-supporting part is inclined and the angle between the supporting surface of the second sub-supporting part and the horizontal plane is an acute angle, the wafer can be limited at the angle position formed by the first sub-supporting part and the second sub-supporting part, so that the contact area between the wafer edge and the susceptor is greatly reduced, the friction area is reduced, the particulate matter generated by friction becomes less, and even if particulate matter is generated, the generated particulate matter will only fall at the angle position formed by the first sub-supporting part and the second sub-supporting part, and the area of the susceptor contaminated by particulate matter will be greatly reduced, effectively improving the pollution situation. At the same time, due to the reduction of the lateral displacement of the wafer caused by thermal expansion, the wafer is not easily displaced, thereby effectively preventing the wafer from sliding.

[0012] In a possible implementation of the first aspect, the bottom plate is circular, the top plate is circular, the length of the first sub-support portion in the radial direction of the bottom plate is L1, the length of the second sub-support portion in the radial direction of the bottom plate is L2, and the total length of L1 and L2 is determined according to the diameter of the wafer to be carried.

[0013] Since the sum of the length of the first sub-support portion in the radial direction of the bottom plate of the susceptor and the length of the second sub-support portion in the radial direction of the bottom plate is determined according to the diameter of the wafer to be carried, it is possible to avoid the wafer falling off the susceptor due to the first and second sub-support portions being too short, and it is also possible to avoid the anti-slip effect of the wafer being affected due to the first and second sub-support portions being too long.

[0014] In a possible implementation of the first aspect, the numerical range of the total length of L1 and L2 is: 5% to 10% of the wafer diameter.

[0015] In this way, it is possible to avoid the wafer falling off the susceptor due to the first and second sub-support portions being too short, and it is also possible to avoid the anti-slip effect of the wafer being affected due to the first and second sub-support portions being too long. According to experience, assuming that the sum of the length of the first sub-support portion in the radial direction of the susceptor bottom plate and the length of the second sub-support portion in the radial direction of the susceptor bottom plate is set to 5% of the wafer diameter, then only a 2 mm area at the wafer edge contacts the support portion.

[0016] In a possible implementation of the first aspect, the second angle between the support surface of the second sub-support portion facing the top plate and the horizontal plane is 0 degrees, and the horizontal plane is perpendicular to the extending direction of the support column. In other words, the support surface of the second sub-support portion facing the top plate and the horizontal plane are parallel.

[0017] In a possible implementation of the first aspect, a convex portion is further provided on the second sub-support portion, and the convex portion is located in the central region of the above support surface.

[0018] In a possible implementation of the first aspect, the convex portion is a hemispherical protrusion, the height of the convex portion is 2 mm, and the radius is 2 mm.

[0019] Since a hemispherical protrusion is further provided on the second sub-support portion, the wafer can be limited between the first sub-support portion and the hemispherical protrusion, and the lateral displacement of the wafer caused by thermal expansion is further reduced, effectively preventing the wafer from sliding. Since the contact area between the wafer edge and the second sub-support portion can be further reduced, the generation of particulate matter due to the friction of the contact surface between the wafer and the support portion is further reduced, improving the cleanliness of the wafer.

[0020] In a possible implementation of the first aspect, the material of each support portion and the support column is silicon carbide.

[0021] In a possible implementation of the first aspect, each support portion and the support column are integrally formed, making the support portion more firm.

[0022] In the present application, a plurality of support columns are provided between the bottom plate and the top plate of the susceptor. A plurality of support portions are respectively provided on the same support column. A first sub-support portion fixedly connected to the support column is respectively provided on each support portion, and a second sub-support portion fixedly connected to the first sub-support portion is provided. The second sub-support portion is disposed at an end of the first sub-support portion away from the support column. When the susceptor needs to carry wafers, the wafers are placed on the support surface of the second sub-support portion. Since the thickness of the first sub-support portion is greater than that of the second sub-support portion, a step can be formed, and the height of the highest point in the second sub-support portion is less than the height of the first sub-support portion, resulting in a smaller contact area between the wafer and the susceptor. When the susceptor expands due to heat and generates vibration or deformation, the lateral displacement of the wafer is reduced, effectively preventing the wafer from sliding. And because the contact area between the wafer and the susceptor is smaller, it helps to reduce the particulate matter generated by friction between the wafer and the susceptor, making the wafer cleaner. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 Shows a structural diagram of a susceptor in a related technical solution; Figure 2A Shows a side view of a susceptor in a related technical solution; Figure 2B Shows Figure 2A The top view of the susceptor in; Figure 3A Shows a side view of a susceptor provided by an embodiment of the present application; Figure 3B Shows Figure 3A The top view of the susceptor in; Figure 3C Shows Figure 3A The schematic diagram of the angle between the second support portion and the horizontal plane in; Figure 3D Shows Figure 3A The schematic diagram of the length of the first sub-support portion along the radial direction of the bottom plate in; Figure 3E Shows Figure 3A The schematic diagram of the length of the second sub-support portion along the radial direction of the bottom plate in; Figure 4AShows a side view of another susceptor provided by an embodiment of the present application; Figure 4B Shows Figure 4A a top view of the susceptor in

[0025] Description of reference numerals 10. Susceptor; 11. Support column; 12. Support portion; 13. First sub-support portion; 14. Second sub-support portion; 15. Convex portion; 16. Top plate; 17. Bottom plate; 18. Support surface. Detailed implementation manners

[0026] Unless otherwise defined, the technical terms or scientific terms used in this specification and the claims should have the ordinary meanings understood by those of ordinary skill in the technical field to which the present invention belongs. The following will describe the specific implementation manners of the present invention with reference to the drawings. It should be noted that in the process of the specific description of these implementation manners, for the sake of concise description, this specification may not describe all the features of the actual implementation manners in detail. Without departing from the spirit and scope of the present invention, those skilled in the art can modify and replace the implementation manners of the present invention, and the obtained implementation manners are also within the protection scope of the present invention.

[0027] The illustrative embodiments of the present application include, but are not limited to, a susceptor. By providing a plurality of support columns between the bottom plate and the top plate of the susceptor, a plurality of support portions are respectively provided on the same support column, a first sub-support portion fixedly connected to the support column is respectively provided on each support portion, and a second sub-support portion fixedly connected to the first sub-support portion is provided, and the second sub-support portion is provided at one end of the first sub-support portion away from the support column. When the susceptor needs to carry a wafer, the wafer is placed on the support surface of the second sub-support portion. Since the thickness of the first sub-support portion is greater than the thickness of the second sub-support portion, a step can be formed, and the height of the highest point in the second sub-support portion is less than the height of the first sub-support portion, so that the contact area between the wafer and the susceptor is small. When the susceptor expands due to heat and generates vibration or deformation, the lateral displacement of the wafer is reduced, effectively preventing the wafer from sliding. And because the contact area between the wafer and the susceptor is small, it helps to reduce the particulate matter generated by friction between the wafer and the susceptor, making the wafer cleaner.

[0028] In order to make the purpose, technical solution and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0029] Figure 1 Shows a structural diagram of a susceptor in the related art solution. Figure 1The susceptor therein includes a plurality of support columns for carrying the susceptor. For example, in related technical solutions, it is necessary for the susceptor to stably feed multiple wafers into a high-temperature furnace tube for heat treatment. During the heat treatment process, the susceptor is prone to thermal stress deformation at high temperatures, resulting in easy sliding or offset of the wafers. Moreover, the contact area between the susceptor and the wafers is large, that is to say, the friction surface of the wafers is large, so that during the contact process between the wafers, more particulate matter drops, resulting in low cleanliness of the wafers.

[0030] Figure 2A FIG. 4 shows a side view of a susceptor in a related technical solution, Figure 2B showing Figure 2A a top view of the susceptor therein. Refer to Figure 2A and Figure 2B In the susceptor design shown, a support surface is provided on the support columns of the susceptor. If the susceptor is placed on Figure 2A and Figure 2B the support surfaces shown, when the susceptor carries wafers, the wafers are placed on the support surfaces. Since Figure 2A and Figure 2B the support surfaces shown are arranged in the horizontal direction, the contact area between the wafers and the susceptor is large. When the susceptor expands and vibrates or deforms due to heat, the lateral displacement of the wafers is large and the wafers slide significantly. And since Figure 2A and Figure 2B the contact area between the wafers and the susceptor shown is large, the friction surface between the wafers and the susceptor is large, and more particulate matter is generated due to the friction between the wafers and the susceptor, resulting in low cleanliness of the wafers and possibly not meeting the requirements of industrial production.

[0031] To solve the problems of wafer sliding and excessive particulate matter existing in the susceptor carrying wafers during the heat treatment process in related technical solutions, some embodiments of the present application provide a susceptor, and the structure of the susceptor is as shown in Figure 3A and 3B shown.

[0032] Refer to Figure 3A and Figure 3B The susceptor 10 shown, includes: a bottom plate 17, a top plate 16, and a plurality of support columns 11 located between the bottom plate 17 and the top plate 16. A plurality of support portions 12 are respectively provided on each support column 11, and two adjacent support portions 12 on the same support column 11 are spaced apart by a specified distance. In other words, the plurality of support portions 12 on each support column 11 are evenly distributed, facilitating batch placement of wafers and improving production efficiency. Among them, the specified distance between two adjacent support portions 12 on each support column 11 can be set as required, and the present application does not limit this.

[0033] In some embodiments, the bottom plate 17 of the susceptor 10 is circular, the top plate 16 is circular, the first sub-support portion 13 is fixedly connected to the support column 11, the second sub-support portion 14 is fixedly connected to the first sub-support portion 13 and is disposed at one end of the first sub-support portion 13 away from the support column 11. The thickness of the first sub-support portion 13 is greater than that of the second sub-support portion 14 to form a step, and the step surface can prevent frictional particles from falling. The height of the highest point in the second sub-support portion 14 is less than the height of the first sub-support portion 13, and the highest point is used to support the wafer. When the susceptor 10 carries a wafer, the wafer is placed on the support surface 18 of the second sub-support portion 14. Since the thickness of the first sub-support portion 13 is greater than that of the second sub-support portion 14, the first sub-support portion 13 and the second sub-support portion 14 can form a step, and the step surface can prevent particulate matter from falling. And since the height of the highest point in the second sub-support portion 14 is less than the height of the first sub-support portion 13, the contact area between the wafer and the susceptor 10 is small. When the susceptor 10 expands due to heat and generates vibration or deformation, the lateral displacement of the wafer is reduced, effectively preventing the wafer from sliding. And since the contact area between the wafer and the susceptor 10 is small, the friction surface between the wafer and the susceptor 10 is small, which can reduce the particulate matter generated by the friction between the wafer and the susceptor 10 and improve the cleanliness of the wafer.

[0034] Reference Figure 3A and Figure 3B , the first sub-support portion 13 protrudes upward relative to the second sub-support portion 14. The surface of the first sub-support portion 13 on the side close to the central axis of the susceptor 10 is a concave surface, the radius of curvature of the concave surface is 3 mm, and the thickness of the first sub-support portion 13 is 5 mm.

[0035] Since the surface of the first sub-support portion 13 on the side close to the central axis of the susceptor 10 is a concave surface, and the surface of the first sub-support portion 13 on the side close to the center of the susceptor 10 matches the edge of the wafer. Therefore, when the susceptor 10 carries the wafer, the wafer is placed on the support surface 18 of the second sub-support portion 14, and the wafer can abut against the concave surface of the first sub-support portion 13, preventing the wafer from sliding, and can block the falling of frictional particles, reducing the contamination of the wafer and improving the yield of the wafer.

[0036] The support surface 18 of the second sub-support portion 14 facing the top plate 16 is inclined toward the top plate 16. Figure 3C Shows Figure 3A a schematic diagram of the angle between the second support portion 14 and the horizontal plane, reference Figure 3A and Figure 3C , the first angle A between the support surface 18 and the horizontal plane is an acute angle, and the horizontal plane is perpendicular to the extending direction of the support column 11. The angle of the first angle A is: 10 degrees to 30 degrees. For example, the first angle A can be 10 degrees, 15 degrees or 30 degrees.

[0037] In some embodiments, the first included angle A between the support surface 18 of the second sub-support portion 14 and the horizontal direction is designed to be 15 degrees, and the contact area between the wafer edge and the susceptor 10 can be reduced to 12% of that of the conventional planar support.

[0038] In Figure 3A and Figure 3B In the illustrated embodiment, the support surface 18 of the second sub-support portion 14 is inclined with respect to the horizontal plane. When the susceptor 10 carries the wafer, the wafer is placed on the support surface 18 of the second sub-support portion 14. Since the support surface 18 of the second sub-support portion 14 facing the top plate 16 is inclined, the wafer can be limited to the included angle position formed by the first sub-support portion 13 and the second sub-support portion 14, so that the contact area between the wafer edge and the susceptor 10 is greatly reduced, the friction area is reduced, the particulate matter generated by friction becomes less, and the cleanliness of the wafer is improved.

[0039] And even if particulate matter is generated, the generated particulate matter will only fall at the included angle position formed by the first sub-support portion 13 and the second sub-support portion 14. It should be understood that since the shape of the surface of the first sub-support portion 13 on the side close to the center of the susceptor 10 is concave in the direction away from the center of the susceptor 10, and the surface of the first sub-support portion 13 on the side close to the center of the susceptor 10 matches the wafer edge, when particulate matter is generated by the friction between the wafer and the susceptor 10, under the action of gravity, the particulate matter generated by the wafer will fall into the concave surface of the first sub-support portion 13. On the one hand, the particulate matter generated by the friction of the wafer is reduced, and on the other hand, the area of the coverage region of the particulate matter on the susceptor 10 will become smaller. In other words, the area of the susceptor 10 contaminated by the particulate matter will be greatly reduced, effectively improving the contamination condition of the wafer. At the same time, due to the reduction of the lateral displacement of the wafer caused by thermal expansion, the wafer is not easy to shift, thereby effectively preventing the wafer from sliding.

[0040] To avoid the support portion 12 being too long or too short and make the anti-slip effect of the wafer better, referring to Figure 3D , in some embodiments of the present application, the length of the first sub-support portion 13 in the radial direction of the bottom plate 17 of the susceptor 10 is denoted as L1, referring to Figure 3E , the length of the second sub-support portion 14 in the radial direction of the bottom plate 17 is denoted as L2, and the total length of L1 and L2 is determined according to the diameter of the wafer to be carried.

[0041] Since the sum of the length of the first sub-support portion 13 in the radial direction of the bottom plate 17 of the susceptor 10 and the length of the second sub-support portion 14 in the radial direction of the bottom plate 17 of the susceptor 10 is determined according to the diameter of the wafer, it is possible to avoid the wafer falling off the susceptor 10 due to the first sub-support portion 13 and the second sub-support portion 14 being too short, and it is also possible to avoid affecting the anti-slip effect of the wafer due to the first sub-support portion 13 and the second sub-support portion 14 being too long.

[0042] For example, in some embodiments, the numerical range of the total length of L1 and L2 is: 5% to 10% of the wafer diameter. For example, the total length of L1 and L2 can be 5%, 6%, 7.5% or 10%.

[0043] In this way, it is possible to avoid the wafer falling off the susceptor 10 due to the too short first sub-support portion 13 and the second sub-support portion 14, and reduce the risk of wafer breakage during dropping. It is also possible to avoid the anti-slip effect of the wafer being affected due to the too long first sub-support portion 13 and the second sub-support portion 14. According to experience, assuming that the sum of the length of the first sub-support portion 13 along the radial direction of the bottom plate 17 of the susceptor 10 and the length of the second sub-support portion 14 along the radial direction of the bottom plate 17 of the susceptor 10 is set to 5% of the wafer diameter, then only a 2 mm area at the wafer edge contacts the support portion.

[0044] It is not difficult to understand that in Figures 3A to 3B In the illustrated embodiment, when the susceptor 10 carries the wafer, the wafer is placed on the support surface 18 of the second sub-support portion 14. Since the support surface 18 of the second sub-support portion 14 facing the top plate 16 is inclined, and the angle between the support surface 18 and the horizontal plane is an acute angle, the wafer can be limited to the angular position formed by the first sub-support portion 13 and the second sub-support portion 14, so that the contact area between the wafer edge and the susceptor 10 is small, the friction area is small, the particulate matter generated by friction is less, and the wafer cleanliness is high. When particulate matter is generated, the generated particulate matter will only fall in the angular region formed by the first sub-support portion 13 and the second sub-support portion 14. And since the surface of the first sub-support portion 13 in contact with the wafer is a concave surface recessed toward the support post 11, when particulate matter is generated by the friction between the wafer and the susceptor 10, under the action of gravity, the particulate matter will fall into the concave surface of the first sub-support portion 13, and the area of the susceptor 10 contaminated by the particulate matter is small, effectively improving the contamination condition of the wafer. It can not only effectively prevent the wafer from sliding, but also improve the cleanliness of the wafer.

[0045] The following introduces another susceptor 10 provided by the present application, as shown in Figure 4A and Figure 4B shown. Figure 4A and Figure 4B The susceptor 10 shown in is only different from the susceptor 10 shown in Figure 3A and Figure 3B in the structural design of the second support 14 portion. Figure 4A and Figure 4B The first support portion 13 of the susceptor 10 shown in is the same as the first support portion 13 of the susceptor 10 shown in Figure 3A and Figure 3B shown. The following mainly introduces the second support portion 14 of the susceptor 10 shown in 4A and Figure 4B shown in detail.

[0046] Reference Figure 4A and Figure 4B The second included angle between the support surface 18 of the second sub-support portion 14 facing the top plate 16 and the horizontal plane is 0 degrees, and the horizontal plane is perpendicular to the extending direction of the support column 11. In other words, the support surface 18 of the second sub-support portion 14 facing the top plate 16 and the horizontal plane are parallel. Figure 4A and Figure 4B A convex portion 15 is further provided on the second sub-support portion 14 shown in the figure. The convex portion 15 is located in the central region of the support surface 18 of the second sub-support portion 14. In some embodiments, the convex portion 15 on the second sub-support portion 14 is hemispherical, the height of the convex portion 15 is 2 mm, and the radius is 2 mm. Then the contact area between the wafer edge and the susceptor 10 is reduced by 15% relative to Figure 2A and Figure 2B the susceptor 10 shown in the figure, and at the same time, the lateral displacement amount of the wafer caused by thermal expansion is reduced.

[0047] Since a hemispherical convex portion 15 is provided on the second sub-support portion 14, when the susceptor 10 carries the wafer, the wafer is placed on the support surface 18 of the second sub-support. The hemispherical convex portion 15 and the first sub-support portion 13 can limit the wafer between the first sub-support portion 13 and the convex portion 15, and the lateral displacement amount of the wafer caused by thermal expansion is further reduced, effectively preventing the wafer from sliding. Since the contact area between the wafer edge and the second sub-support portion 14 can be further reduced, the generation of particulate matter caused by the friction of the contact surface between the wafer and the support portion is further reduced, and the cleanliness of the wafer is improved.

[0048] In some embodiments, the materials of the support portions 12 and the support columns 11 of the susceptor 10 are both silicon carbide.

[0049] In some embodiments, the support portions 12 and the support columns 11 of the susceptor 10 are integrally formed, so that the support portion 12 is more firm.

[0050] In this application, a plurality of support columns 11 are provided between the bottom plate 17 and the top plate 16 of the susceptor 10. A plurality of support portions 12 are respectively provided on the same support column 11. A first sub-support portion 13 fixedly connected to the support column 11 and a second sub-support portion 14 fixedly connected to the first sub-support portion 13 are respectively provided on each support portion 12. The second sub-support portion 14 is provided at one end of the first sub-support portion 13 away from the support column 11. When the susceptor 10 needs to carry wafers, the wafers are placed on the support surface 18 of the second sub-support portion 14. Since the thickness of the first sub-support portion 13 is greater than that of the second sub-support portion 14, a step can be formed, and the height of the highest point in the second sub-support portion 14 is less than the height of the first sub-support portion 13. The support columns 11 of the susceptor 10, the first sub-support portion 13, the support columns 11, the second sub-support portion 14 of the susceptor 10, the first sub-support portion 13, and the second sub-support portion 14 of the susceptor 10 make the contact area between the wafers and the susceptor 10 relatively small. When the susceptor 10 expands due to heat and vibrates or deforms, the lateral displacement of the wafers is reduced, effectively preventing the wafers from sliding. Moreover, since the contact area between the wafers and the susceptor 10 is relatively small, it helps to reduce the particulate matter generated by friction between the wafers and the susceptor 10, making the wafers cleaner.

[0051] In the drawings, some structural or susceptor features may be shown in a particular arrangement and / or order. However, it should be understood that such a particular arrangement and / or ordering may not be required. Instead, in some embodiments, these features may be arranged in a manner and / or order different from that shown in the illustrative drawings. Additionally, the inclusion of a structural or susceptor feature in a particular figure does not imply that such a feature is required in all embodiments, and in some embodiments, these features may not be included or may be combined with other features.

[0052] It should be noted that in the examples and descriptions of this patent, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process, susceptor, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or elements inherent to such process, susceptor, article or device. Without further limitation, an element defined by the statement "comprising one" does not exclude the presence of additional identical elements in the process, susceptor, article or device comprising the element.

[0053] Although this application has been illustrated and described by reference to certain preferred embodiments of this application, those of ordinary skill in the art should understand that various changes can be made in form and detail without departing from the spirit and scope of this application.

Claims

1. A susceptor, characterized in that, Comprising: A bottom plate, a top plate, and a plurality of support columns located between the bottom plate and the top plate; A plurality of support portions are respectively provided on each of the support columns, and there is a gap between two adjacent support portions on the same support column; Each of the support portions respectively includes a first sub-support portion and a second sub-support portion. The first sub-support portion is fixedly connected to the support column. The second sub-support portion is fixedly connected to the first sub-support portion and is disposed at an end of the first sub-support portion away from the support column. The thickness of the first sub-support portion is greater than the thickness of the second sub-support portion to form a step. The height of the highest point in the second sub-support portion is less than the height of the first sub-support portion, and the highest point is used to support the wafer.

2. The susceptor according to claim 1, wherein The surface of the first sub-support portion on the side close to the central axis of the susceptor is a concave surface, the radius of curvature of the concave surface is 3 mm, and the thickness of the first sub-support portion is 5 mm.

3. The susceptor according to claim 2, wherein, The support surface of the second sub-support portion facing the top plate is inclined towards the top plate. The first angle between the support surface and the horizontal plane is an acute angle, and the horizontal plane is perpendicular to the extending direction of the support column.

4. The susceptor according to claim 3, wherein, The angle of the first angle is from 10 degrees to 30 degrees.

5. The susceptor according to claim 3, wherein The bottom plate is circular, the top plate is circular, the length of the first sub-support portion in the radial direction of the bottom plate is L1, the length of the second sub-support portion in the radial direction of the bottom plate is L2, and the total length of L1 and L2 is determined according to the diameter of the wafer to be carried.

6. The susceptor according to claim 5, wherein The numerical range of the total length of L1 and L2 is: 5% to 10% of the wafer diameter.

7. The susceptor according to claim 2, wherein The angle of the second angle between the support surface of the second sub-support portion facing the top plate and the horizontal plane is 0 degree, and the horizontal plane is perpendicular to the extending direction of the support column.

8. The susceptor according to claim 7, wherein A convex portion is further provided on the second sub-support portion, and the convex portion is located in the central area of the support surface.

9. The susceptor according to claim 8, wherein, The convex portion is a hemispherical protrusion, the height of the convex portion is 2 mm, and the radius is 2 mm.

10. The susceptor according to claim 1, characterized in that, The material of each of the support portions and each of the support columns is silicon carbide; or, each of the support portions and each of the support columns are integrally formed.

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