Silicon carbide bearing table

Abstract

The silicon carbide wafer bearing table comprises a plate part, the front face of the plate part comprises a center circular table face and a peripheral front face circular ring face, the back face of the plate part comprises a center circular sinking groove, a first peripheral back face circular ring face and a second peripheral back face circular ring face which are concentric, and three ejector pin passing holes are formed in the plate part. A plurality of groups of linear rows of air suction holes are formed in the central circular truncated cone surface, a plurality of ventilation channels are formed in the side wall of the plate part, vacuumizing holes are formed in the back surface of the plate part, a mounting groove is further formed in the front surface of the plate part, the outer side of the mounting groove penetrates through the periphery of the plate part to form an opening structure, and a positioning through hole is formed in the mounting groove; an avoiding groove is formed in the inner side wall of the mounting groove, two positioning structures are further arranged on the front face of the plate part and located on the annular face of the front face of the periphery, and the positioning structures and positioning columns in the avoiding groove position the wafer in a three-point mode. The silicon carbide wafer bearing platform can reduce the processing difficulty and meet the wafer carrying requirements of wafers.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor wafers, and in particular to a silicon carbide wafer stage. Background Art

[0002] The silicon carbide wafer stage is one of the most important parts of the workpiece stage of the photolithography machine, which is used to carry silicon wafers. The invention application document with patent publication number CN116810972A discloses a molding process for a silicon carbide wafer stage. The silicon carbide wafer stage processed by the molding process has a specific structure including a plate portion, the front side of which includes a central circular table surface and a peripheral front circular annular surface outside the central circular table surface, and the peripheral front circular annular surface is lower than the central circular table surface; the back side of the plate portion includes a concentric central circular groove, a first peripheral back circular annular surface and a second peripheral back circular annular surface, the central circular groove is located at the center of the plate portion, the first peripheral back circular annular surface is located outside the central circular groove, and the second peripheral back circular annular surface is located outside the central circular groove. The annular surface is outside the first outer peripheral back annular surface and lower than the first outer peripheral back annular surface; three ejector holes arranged in an equilateral triangle and located on the central circular table are arranged on the plate portion, and a mounting strip hole is also arranged on the plate portion, which is located on the outer peripheral front annular surface and passes through the plate portion. The back side of the plate portion is provided with inner straight strip grooves and outer straight strip grooves on the inner and outer sides of the mounting strip holes, and the bottom of the inner straight strip groove is higher than the outer straight strip groove. Two strip arc grooves are arranged on the first outer peripheral back annular surface on the back side of the plate portion; and a vacuum hole, a positioning hole and a mounting hole are provided.

[0003] However, this silicon carbide wafer table has the following disadvantages: 1. The wafer table has a mounting bar hole, and the mounting bar hole runs through the plate as a whole, so it is difficult to process the mounting bar hole; 2. The central circular table surface of the wafer table needs to be engraved on a laser engraving machine to form support bumps, and the support bumps are used to support the wafer, and the support bumps are very difficult to process, and when processing the support bumps on the wafer table, what is actually engraved are other areas between the support bumps, resulting in a very large area that requires laser engraving, so that there are more areas that are lost in the engraving, and the energy consumption of the laser engraving machine is also very large. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a silicon carbide wafer stage, which can reduce the processing difficulty and meet the wafer loading requirements.

[0005] In order to solve the above technical problems, the technical solution of the present invention is: a silicon carbide wafer table, including a plate portion, the front side of the plate portion includes a central circular table surface and a peripheral front circular annular surface outside the central circular table surface, and the peripheral front circular annular surface is lower than the central circular table surface; the back side of the plate portion includes a concentric central circular groove, a first peripheral back circular annular surface and a second peripheral back circular annular surface, the central circular groove is located at the center of the plate portion, the first peripheral back circular annular surface is outside the central circular groove, and the second peripheral back circular annular surface is outside the first peripheral back circular annular surface and lower than the first peripheral back circular annular surface; three ejector pin passing holes arranged in an equilateral triangle and located on the central circular table surface are provided on the plate portion, and a plurality of groups of suction hole straight lines are provided on the central circular table surface, and each group of suction hole straight lines includes a plurality of straight lines arranged in a straight line The air intake holes are arranged in a row, and the air intake holes spread outward from the middle of the central circular table surface. A plurality of ventilation channels are arranged on the side walls of the plate portion, and the ventilation channels correspond to each group of straight lines of air intake holes one by one to connect the air intake holes. The ends of the ventilation channels are sealed. The back side of the plate portion is provided with a vacuum hole connected with each ventilation channel. The front side of the plate portion is also provided with a mounting groove for convenient installation of a positioning mechanism. The outer side of the mounting groove passes through the outer periphery of the plate portion to form an opening structure. A positioning through hole is arranged in the mounting groove. The inner side wall of the mounting groove is provided with an avoidance groove for convenient avoidance of the positioning column of the positioning mechanism. The front side of the plate portion is located on the outer peripheral front annular surface. Two positioning structures for positioning the wafer on the central circular table surface are also arranged. The positioning structure and the positioning column in the avoidance groove position the wafer at three points.

[0006] As a preferred solution, a plurality of concentric circular grooves are further provided on the central circular table surface, and the air suction holes are all located in the corresponding concentric circular grooves.

[0007] As a preferred solution, the positioning structure includes a positioning shaft fixedly mounted on the outer peripheral front annular surface, a positioning plate is rotatably mounted on the positioning shaft, the bottom plate surface of the positioning plate extends into the central circular table surface, and the two positioning plates and the positioning column constitute a three-point support.

[0008] As a preferred solution, the bottom surface of the positioning plate is flush with the center circular table surface.

[0009] As a preferred solution, the two positioning plates and the positioning post form an isosceles triangle with the positioning post as the vertex.

[0010] As a preferred solution, at least one positioning countersunk hole is also provided on the annular surface of the first outer circumference back side.

[0011] As a preferred solution, the positioning countersunk hole includes a circular countersunk hole and a strip countersunk hole.

[0012] After adopting the above technical scheme, the effect of the present invention is as follows: since the front of the plate part is also provided with a mounting groove for facilitating the installation of the positioning mechanism, the outer side of the mounting groove penetrates the outer periphery of the plate part to form an opening structure, a positioning through hole is provided in the mounting groove, and an avoidance groove is provided on the inner side wall of the mounting groove for facilitating the avoidance of the positioning column of the positioning mechanism, the front of the plate part is located on the outer front annular surface and is also provided with two positioning structures for positioning the wafer on the central circular table surface, and the positioning structure and the positioning column in the avoidance groove position the wafer at three points, therefore, only the mounting groove is processed on the plate part without processing the through hole, and the installation of the positioning mechanism can be facilitated in the mounting groove, and the accurate assembly of the positioning mechanism can be facilitated through the positioning through hole, and at the same time, the positioning column on the positioning mechanism is adapted to the avoidance groove, so that the overall installation of the positioning mechanism is not only convenient, but also reduces the processing difficulty. The positioning column and the other two positioning structures cooperate with each other to facilitate the positioning of the wafer.

[0013] Since a number of concentric circular grooves are provided on the central circular table, the air suction holes are all located in the corresponding concentric circular grooves. Therefore, the air suction holes are located in the concentric circular grooves. When the wafer is placed on the central circular table, it will be supported by the central circular table. At the same time, negative pressure will be drawn in the concentric circular grooves, so that the wafer can be reliably fixed on the silicon carbide wafer, and the overall force on the wafer is more uniform.

[0014] Furthermore, since the positioning structure includes a positioning shaft fixedly mounted on the outer peripheral front annular surface, a positioning plate is rotatably mounted on the positioning shaft, and the bottom plate surface of the positioning plate extends into the central circular table surface, the two positioning plates and the positioning column form a three-point support. Therefore, the edge positioning of the wafer can be better facilitated by using the rotating positioning plate, and the wafer can be conveniently rotated during the positioning process, thereby better adjusting the position of the wafer.

[0015] Furthermore, since the bottom surface of the positioning plate is flush with the central circular table surface, the wafer can be better positioned to prevent the wafer from entering the gap between the positioning plate and the central circular table surface.

[0016] Furthermore, since the two positioning plates and the positioning post form an isosceles triangle with the positioning post as the vertex, the position of the wafer can be adjusted more smoothly during position adjustment.

[0017] Furthermore, since at least one positioning countersunk hole is provided on the annular surface on the back of the first outer periphery, the positioning countersunk hole includes a circular countersunk hole and a strip countersunk hole, thus assembling the silicon carbide wafer stage can be more convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0019] Figure 1 is a three-dimensional structural diagram of an embodiment of the present invention;

[0020] Figure 2 is a reverse perspective view of an embodiment of the present invention;

[0021] In the attached drawings: 1, plate; 2, center circular table surface; 3, outer peripheral front annular surface; 4, installation groove; 5, avoidance groove; 6, positioning through hole; 7, ejector pin through hole; 8, suction hole; 9, concentric groove; 10, positioning plate; 11, strip countersunk hole; 12, vacuum hole; 13, ventilation channel; 14, center circular countersunk groove; 15, first outer peripheral back annular surface; 16, second outer peripheral back annular surface; 17, circular countersunk hole. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below through specific examples.

[0023] like Figure 1 and Figure 2 As shown, a silicon carbide wafer carrier comprises a plate portion 1, the front face of the plate portion 1 comprises a central circular table surface 2 and a peripheral front circular annular surface 3 located outside the central circular table surface 2, the peripheral front circular annular surface 3 being lower than the central circular table surface 2; the back face of the plate portion 1 comprises a concentric central circular groove 14, a first peripheral back circular annular surface 15 and a second peripheral back circular annular surface 16, the central circular groove 14 is located at the center of the plate portion 1, the first peripheral back circular annular surface 15 is located outside the central circular groove 14, the second peripheral back circular annular surface 16 is located outside the first peripheral back circular annular surface 15 and is lower than the first peripheral back circular annular surface 15; the plate portion 1 is provided with three equilateral triangles arranged on the central circular table surface 2 A pin passing hole 7 is provided, and a plurality of groups of straight lines of air suction holes 8 are arranged on the central frustum table 2, and each group of straight lines of air suction holes 8 includes a plurality of straightly arranged air suction holes 8, and the air suction holes 8 diffuse outward from the middle of the central frustum table 2, and a plurality of ventilation channels are provided on the side wall of the plate portion 1, and the ventilation channels correspond to each straight line of air suction holes 8 one by one to connect the air suction holes 8, and the ends of the ventilation channels are sealed, and a vacuum hole 12 connected to each ventilation channel is provided on the back side of the plate portion 1, and the vacuum hole 12 is used for installing a vacuum nozzle, and the vacuum nozzle is used to connect with the vacuum system, and the ventilation channels are connected to each other, so the number of the vacuum hole 12 is one, so that all the ventilation channels can be evacuated by one vacuum nozzle.

[0024] The front of the plate portion 1 is also provided with a mounting groove 4 for facilitating the installation of a positioning mechanism. The outer side of the mounting groove 4 passes through the outer periphery of the plate portion 1 to form an opening structure. A positioning through hole 6 is provided in the mounting groove 4. The inner side wall of the mounting groove 4 is provided with an avoidance groove 5 for conveniently avoiding the positioning column of the positioning mechanism. The front of the plate portion 1 is located on the outer peripheral front annular surface 3 and is also provided with two positioning structures for positioning the wafer on the central circular table surface 2. The positioning structure and the positioning column in the avoidance groove 5 position the wafer at three points.

[0025] The positioning mechanism in this embodiment is a conventional positioning mechanism for the current silicon carbide wafer stage, which mainly includes a mounting plate and a positioning column. Since the mounting groove 4 is provided in this embodiment, the mounting plate is directly installed in the mounting groove 4, and the mounting plate is adapted to the positioning through hole 6 in the mounting groove 4 through the positioning pin to complete the overall positioning installation. The positioning column is located in the avoidance groove 5, and the positioning column has a radial elastic sliding displacement, so that the position of the wafer can be pushed and adjusted when the wafer is placed. Finally, when the positioning column falls into the avoidance groove 5, it constrains the positioning wafer together with other positioning structures.

[0026] like Figure 1 As shown, a plurality of concentric circular grooves 9 are also provided on the central circular table 2, and the suction holes 8 are all located in the corresponding concentric circular grooves 9. When the wafer is placed on the central circular table 2 and the suction holes 8 are sucked, the entire concentric circular grooves 9 will generate negative pressure, thereby adsorbing the wafer as a whole. The vacuum adsorption effect is good and the force is more reasonable. At the same time, due to the setting of the concentric circular grooves 9, the processing difficulty of the concentric circular grooves 9 is lower than that of the supporting protrusions that need to be processed in the background technology, and the processing accuracy requirements of the concentric circular grooves 9 are also lower.

[0027] like Figure 1 As shown, the positioning structure includes a positioning shaft fixedly mounted on the outer front annular surface 3, a positioning plate 10 is rotatably mounted on the positioning shaft, the bottom plate surface of the positioning plate 10 extends into the central circular table surface 2, and the two positioning plates 10 and the positioning column form a three-point support. The bottom plate surface of the positioning plate 10 is flush with the central circular table surface 2, and preferably the positioning plate 10 and the central circular table surface 2 are in contact with each other.

[0028] The two positioning plates 10 and the positioning column form an isosceles triangle with the positioning column as the vertex. At least one positioning countersunk hole is also provided on the first outer peripheral back annular surface 15. The positioning countersunk hole includes a circular countersunk hole 17 and a strip countersunk hole 11.

[0029] Among them, the positioning countersunk holes are mainly used to facilitate better positioning of the wafer table during installation and ensure the accuracy of the installation angle.

[0030] The above-described embodiments are merely descriptions of preferred implementations of the present invention and are not intended to limit the scope of the present invention. Various modifications and alterations to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A silicon carbide wafer table, comprising a plate portion, the front side of the plate portion comprising a central circular table surface and a peripheral front circular annular surface outside the central circular table surface, the peripheral front circular annular surface being lower than the central circular table surface; the back side of the plate portion comprising a concentric central circular groove, a first peripheral back circular annular surface and a second peripheral back circular annular surface, the central circular groove being located at the center of the plate portion, the first peripheral back circular annular surface being located outside the central circular groove, the second peripheral back circular annular surface being located outside the first peripheral back circular annular surface and being lower than the first peripheral back circular annular surface; the plate portion is provided with three ejector pin holes arranged in an equilateral triangle and located on the central circular table surface, characterized in that: The central circular table is provided with a plurality of straight lines of suction holes, each group of straight lines of suction holes includes a plurality of suction holes arranged in a straight line, and the suction holes spread outward from the middle of the central circular table; the side walls of the plate are provided with a plurality of ventilation channels, and the ventilation channels correspond to each group of straight lines of suction holes one by one to connect the suction holes; the ends of the ventilation channels are sealed; the back of the plate is provided with a vacuum hole connected with each ventilation channel; the front of the plate is also provided with a mounting groove for facilitating the installation of a positioning mechanism; the outer side of the mounting groove passes through the outer periphery of the plate to form an opening structure; a positioning through hole is provided in the mounting groove; an avoidance groove is provided on the inner side wall of the mounting groove for facilitating the avoidance of a positioning column of the positioning mechanism; the front of the plate is located on the outer peripheral front annular surface; and two positioning structures for positioning the wafer on the central circular table are also provided; the positioning structure and the positioning column in the avoidance groove position the wafer at three points.

2. A silicon carbide wafer stage according to claim 1, characterized in that: The central circular table surface is also provided with a plurality of concentric circular grooves, and the air suction holes are all located in the corresponding concentric circular grooves.

3. A silicon carbide wafer stage according to claim 2, characterized in that: The positioning structure comprises a positioning shaft fixedly mounted on the outer peripheral front annular surface, a positioning plate rotatably mounted on the positioning shaft, the bottom plate surface of the positioning plate extends into the central circular table surface, and two positioning plates and the positioning column form a three-point support.

4. A silicon carbide wafer stage according to claim 3, characterized in that: The bottom plate surface of the positioning plate is flush with the central circular table surface.

5. The silicon carbide wafer stage according to claim 4, characterized in that: The two positioning plates and the positioning post form an isosceles triangle with the positioning post as the vertex.

6. The silicon carbide wafer stage according to claim 5, characterized in that: At least one positioning countersunk hole is also provided on the annular surface of the first outer peripheral back side.

7. The silicon carbide wafer stage according to claim 6, characterized in that: The positioning countersink includes a circular countersink and a bar countersink.

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