Tray for epitaxy and epitaxy equipment

Abstract

The invention provides a tray for epitaxy and epitaxy equipment. The tray for extension comprises: a tray body; the side wall is arranged around the tray body and comprises an inclined surface, the inclined surface is used for supporting a wafer, and the inclined surface of the side wall is connected with the tray body through a vertical surface perpendicular to the tray body. The inclined surface of the side wall is connected with the tray body through the vertical surface perpendicular to the tray body, so that the dimension of the lower space of the wafer is consistent along the direction of heating the wafer, and the thermal radiation environment is not changed. And compared with a direct inclined surface, the consistency of a heat radiation environment is ensured.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor equipment, and in particular to an epitaxial tray and an epitaxial equipment. Background Art

[0002] Silicon epitaxy refers to the process of growing homogeneous epitaxial layers on or above a silicon substrate. This process is usually carried out at high temperatures through a gas phase chemical reaction, using a polished silicon single crystal as a substrate. By controlling the growth conditions, an epitaxial layer with good crystal quality and consistent thickness can be obtained. Silicon epitaxial materials are mainly used as important basic materials in the manufacture of various silicon integrated circuits and discrete devices, especially in large-diameter silicon integrated circuit chip production lines, where silicon epitaxy is a commonly used starting material.

[0003] However, in the prior art, we have found that the thickness of the epitaxial layer cannot be uniform, and there will be a thickness change from the center to the periphery, which will affect the implementation of subsequent processes. Therefore, how to obtain an epitaxial layer with uniform thickness is a problem that the prior art needs to solve. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an epitaxial tray and an epitaxial device, which can improve the uniformity of the epitaxial layer.

[0005] In order to solve the above problems, the present invention provides a tray for epitaxial growth, comprising: a tray body; a side wall, wherein the side wall is arranged around the tray body and comprises an inclined surface, wherein the inclined surface is used to support the wafer, and the inclined surface of the side wall is connected to the tray body via a vertical surface perpendicular to the tray body.

[0006] Optionally, the tray is made of graphite and coated with SiC.

[0007] Optionally, the edge of the wafer has a chamfer, and the diameter of the intersection line between the inclined surface and the vertical surface of the side wall is larger than the inner edge diameter of the chamfer and smaller than the outer edge diameter of the chamfer.

[0008] In order to solve the above problems, the present invention provides an epitaxial device, including: a tray for placing wafers; a heater for heating the wafers from the top and bottom of the tray by thermal radiation; the tray includes: a tray body; a side wall, the side wall is arranged around the tray body and includes an inclined surface, the inclined surface is used to support the wafer, and the inclined surface of the side wall is connected to the tray body through a vertical surface perpendicular to the tray body.

[0009] Optionally, the tray is made of graphite and coated with SiC.

[0010] Optionally, the edge of the wafer has a chamfer, and the diameter of the intersection line between the inclined surface and the vertical surface of the side wall is larger than the diameter of the inner edge of the chamfer of the wafer and smaller than the diameter of the outer edge of the chamfer of the wafer.

[0011] The inclined surface of the side wall of the present invention is connected to the tray body through a vertical surface perpendicular to the tray body, which ensures that the size of the space below the wafer is consistent along the direction of heating the wafer, and the thermal radiation environment does not change. Compared with a directly inclined inclined surface, the consistency of the thermal radiation environment is ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Attached Figure 1 Shown is a schematic structural diagram of a specific implementation of the epitaxial device of the present invention.

[0013] Attached Figure 2 Shown is an enlarged schematic diagram of the junction between the tray side wall and the body of the specific implementation mode of the epitaxial device of the present invention. DETAILED DESCRIPTION

[0014] The specific implementation of the epitaxial tray and epitaxial equipment provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0015] Attached Figure 1 The structure diagram of the specific embodiment of the epitaxial device of the present invention is shown in FIG. The epitaxial device comprises a tray 10 and a heater 11 .

[0016] The tray 10 is used to place the wafer 13. The heater 11 includes an upper heater 11a and a lower lower heater 11b. The upper and lower heaters can be a combination of one or more, and in this specific embodiment, there are multiple heaters, which heat the wafer 13 from the middle and the edge respectively. The upper heater 11a and the lower lower heater 11b heat the wafer 13 from the upper and lower parts of the tray 10 by thermal radiation. The material of the tray is graphite and coated with SiC. The wafer 13 can be a wafer of any common semiconductor material including silicon, germanium, silicon carbide, GaAs, and GaN. The epitaxial material on the surface can be a homoepitaxial layer, or a heteroepitaxial layer such as GaN, GaAs, and stressed silicon. The tray 10 can be rotating or stationary, and the upper heater 11a and the lower lower heater 11b can also be independently set to rotate synchronously with the tray 10 or remain relatively stationary.

[0017] In this specific embodiment, the tray 10 includes a tray body 101 and a side wall 102. Figure 2 The figure shows an enlarged schematic diagram of the junction between the side wall and the body of the tray. Figure 2As shown, the side wall 102 is arranged around the tray body 101 and includes a slope 102a. The slope 102a is used to support the wafer 13. The slope 102a of the side wall 102 is connected to the tray body 101 through a vertical surface 102b perpendicular to the tray body 101. Since the heater heats the wafer 13 in the form of thermal radiation, especially the lower heater 11b, the thermal radiation must act on the wafer 13 through the tray body 101. Therefore, the shape of the space between the tray body 101 and the wafer 13 will inevitably affect the effect of thermal radiation. In the above-mentioned setting, the slope 102a of the side wall 102 is connected to the tray body 101 through a vertical surface 102b perpendicular to the tray body 101, which ensures that the size of the space below the wafer 10 is consistent along the direction of heating the wafer, and the thermal radiation environment will not change. Compared with a directly inclined slope (dashed line shape), the consistency of the thermal radiation environment is guaranteed. The dotted-line-shaped inclined surface has a smaller longitudinal space near the edge of the wafer, which may lead to overheating and cause the temperature at the edge of the wafer 13 to be inconsistent with that at the center, thereby affecting the consistency of the thickness of the epitaxial layer.

[0018] Preferably, in this specific embodiment, the edge of the wafer 13 has a chamfer, and the chamfer structure has an inner edge 13a and an outer edge 13b. Figure 2 In the figure, the intersection line of the inclined surface 102a of the side wall and the vertical surface 102b is a point. In the actual three-dimensional structure, this position is a circular intersection line surrounding the tray body 101. In this specific embodiment, the diameter of the circular intersection line should be larger than the diameter of the inner edge 13a of the chamfer, and smaller than the diameter of the outer edge 13b of the chamfer, that is, the intersection line is just stuck on the chamfer of the wafer 13. The epitaxial layer will not grow where the wafer has a chamfer, so this setting can ensure that the thermal environment of the entire effective area of ​​the wafer 13 is the same, and the chamfer can be used to clamp the wafer 13 and the tray 10 to each other.

[0019] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An epitaxial tray, characterized in that: include: Tray body; The side wall is arranged around the tray body and includes an inclined surface, wherein the inclined surface is used to support the wafer, and the inclined surface of the side wall and the tray body are connected to each other through a vertical surface perpendicular to the tray body.

2. The tray for extension according to claim 1, characterized in that: The material of the tray is graphite and coated with SiC.

3. The tray for extension according to claim 1, characterized in that: The edge of the wafer has a chamfer, and the diameter of the intersection line between the inclined surface and the vertical surface of the side wall is larger than the inner edge diameter of the chamfer and smaller than the outer edge diameter of the chamfer.

4. An epitaxial device, comprising: A tray for placing wafers; A heater that heats the wafer from above and below the tray by means of thermal radiation; Characterized in that the tray comprises: Tray body; The side wall is arranged around the tray body and includes an inclined surface, wherein the inclined surface is used to support the wafer, and the inclined surface of the side wall and the tray body are connected to each other through a vertical surface perpendicular to the tray body.

5. The epitaxial device according to claim 4, characterized in that: The material of the tray is graphite and coated with SiC.

6. The epitaxial device according to claim 4, characterized in that: The edge of the wafer has a chamfer, and the diameter of the intersection line between the inclined surface and the vertical surface of the side wall is larger than the diameter of the inner edge of the chamfer of the wafer and smaller than the diameter of the outer edge of the chamfer of the wafer.

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