Bearing apparatus and semiconductor processing device

Abstract

The present disclosure provides a bearing apparatus and a semiconductor processing device. The bearing apparatus comprises a base body, the plane where the base body bears a wafer is a reference plane, the base body is provided with an annular protrusion, and the top surface of the annular protrusion is flush with the reference plane and is used for supporting and sealing the edge area of the wafer; the base body is further provided with a first surface and a second surface which are lower than the reference plane, the first surface is close to the inner peripheral edge of the annular protrusion, the second surface is located in the center area of the base body, and the base body is further provided with a third surface located between the first surface and the second surface and recessed in a direction away from the reference plane; and gas channel structures communicated with each other are distributed in the first, second and third surfaces. The present solution can improve the pressure distribution uniformity between the wafer and a base, thereby improving process uniformity.

Description

Bearing device and semiconductor processing equipment TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor manufacturing, in particular to a bearing device and semiconductor processing equipment. BACKGROUND

[0002] In the process of wafer preparation, especially in the key links such as deposition, lithography and etching, the wafer must be stably fixed and heated (or cooled) to ensure the smooth development of related process operations on the wafer. Therefore, the equipment for fixing and heating (or cooling) the wafer has very high performance requirements. At present, the vacuum chuck heater is a commonly used wafer fixing and heating (or cooling) equipment. The base is fixed by vacuumizing between the wafer and the base, and the wafer is fixed by using the pressure difference between the upper and lower surfaces of the wafer. In addition, the gas between the wafer and the base can play a role in heat conduction, and the top surface of the base can achieve uniform gas effect by designing different gas path shapes.

[0003] The prior art has the problem of uneven distribution of gas space pressure between the wafer and the base, which leads to uneven distribution of wafer temperature, thereby resulting in poor process uniformity (such as film thickness uniformity). SUMMARY

[0004] The present application aims to at least solve one of the technical problems existing in the prior art, and proposes a bearing device and semiconductor processing equipment which can solve the problem of uneven distribution of gas space pressure between the wafer and the base body in the prior art, thereby improving the process uniformity.

[0005] To achieve the purpose of the present application, a bearing device is provided, comprising a base body, the base body carrying a wafer is a reference surface, the base body has an annular convex part, the top surface of the annular convex part is flush with the reference surface, and the annular convex part is used to support and seal the edge region of the wafer; the base body also has a first surface and a second surface lower than the reference surface, the first surface is close to the inner peripheral edge of the annular convex part, the second surface is located in the central region of the base body, and the base body also has a third surface located between the first surface and the second surface and recessed away from the reference surface;

[0006] The first surface, the second surface and the third surface are all distributed with gas channel structures connected in communication.

[0007] In some embodiments, the third surface is a first annular surface surrounding the second surface; or the third surface is a plurality of surfaces surrounding the second surface;

[0008] The first surface is a second annular surface surrounding the first annular surface.

[0009] In some embodiments, the third surface is an arc surface or a stepped surface.

[0010] In some embodiments, the first annular surface and the second annular surface are both circular annular surfaces; the second surface is a circular surface;

[0011] The inner peripheral diameter of the second annular surface is equal to the outer peripheral diameter of the first annular surface; the inner peripheral diameter of the first annular surface is equal to the outer peripheral diameter of the second surface.

[0012] In some embodiments, the airway structure distributed on the second annular surface comprises an annular airway extending along the circumferential direction of the second annular surface.

[0013] In some embodiments, a plurality of adsorption air holes communicating with the airway structure are formed on the second surface, and the centers of the plurality of adsorption air holes are distributed on a circle with the center of the second surface as the center.

[0014] In some embodiments, the ratio of the outer peripheral diameter of the second surface to the diameter of the circle on which the centers of the adsorption air holes are distributed is greater than or equal to 1.2 and less than or equal to 1.8.

[0015] In some embodiments, the ratio of the outer peripheral diameter of the second annular surface to the outer peripheral diameter of the second surface is greater than or equal to 2.35 and less than or equal to 3.73; the ratio of the inner peripheral diameter of the second annular surface to the outer peripheral diameter of the second surface is greater than or equal to 2.16 and less than or equal to 3.48.

[0016] In some embodiments, the outer peripheral diameter of the second annular surface is greater than or equal to 282 mm and less than or equal to 298 mm; the inner peripheral diameter of the second annular surface is greater than or equal to 259 mm and less than or equal to 279 mm.

[0017] In some embodiments, the outer peripheral diameter of the second surface is greater than or equal to 80 mm and less than or equal to 120 mm.

[0018] In some embodiments, the distance between the third surface and the reference surface is 4.5 times to 15 times the distance between the second surface and the reference surface; and / or,

[0019] The distance between the third surface and the reference surface is 4.5 times to 15 times the distance between the first surface and the reference surface.

[0020] In some embodiments, the distance between the second surface and the reference surface is less than or equal to the distance between the first surface and the reference surface.

[0021] In some embodiments, the distance between the second surface and the reference surface is greater than 0 pm and less than or equal to 50 pm; and / or,

[0022] the distance between the first surface and the reference surface is greater than 0 pm and less than or equal to 50 pm.

[0023] In some embodiments, the difference between the distance between the third surface and the reference surface and the distance between the second surface and the reference surface is greater than or equal to 60 pm and less than or equal to 140 pm; and / or,

[0024] the difference between the distance between the third surface and the reference surface and the distance between the first surface and the reference surface is greater than or equal to 60 pm and less than or equal to 140 pm.

[0025] In some embodiments, the depths of the airway structures where the first surface, the second surface and the third surface are distributed are the same.

[0026] In some embodiments, the depths of the airway structures where the first surface, the second surface and the third surface are distributed are greater than or equal to 60 pm and less than or equal to 140 pm.

[0027] In some embodiments, a plurality of protrusions are distributed on the second surface and the third surface, and a top surface of each of the protrusions is flush with the reference surface for supporting a wafer.

[0028] The percentage of the total horizontal cross-sectional area of the protrusions on the second surface to the area of the second surface is greater than the percentage of the total horizontal cross-sectional area of the protrusions on the third surface to the area of the second surface.

[0029] In some embodiments, the percentage of the total horizontal cross-sectional area of the protrusions on the third surface to the area of the second surface is greater than or equal to 0.8% and less than or equal to 2%;

[0030] The percentage of the total horizontal cross-sectional area of the protrusions on the second surface to the area of the second surface is greater than or equal to 1% and less than or equal to 2.2%.

[0031] In some embodiments, a plurality of protrusions are distributed on the second surface and the third surface, and a top surface of each of the protrusions is flush with the reference surface for supporting a wafer.

[0032] The plurality of protrusions on the second surface and the third surface are distributed at least one circle in the circumference of the base body;

[0033] The distance between adjacent protrusions in the same circle on the second surface is less than the distance between adjacent protrusions in the same circle on the third surface; and / or, the radial distance between circumferences of adjacent two circles of protrusions on the second surface is less than the radial distance between circumferences of adjacent two circles of protrusions on the third surface.

[0034] In some embodiments, a plurality of adsorption air holes in communication with the gas passage structure are formed on the second surface, and the bearing device further comprises a base shaft arranged at the bottom of the base body, wherein a gas passage is arranged in the base shaft, one end of the gas passage is in communication with the adsorption air hole, and the other end of the gas passage is used to communicate with a gas extraction device;

[0035] A reduced diameter portion is arranged in the gas passage, and the reduced diameter portion is used to reduce the air passage cross-sectional area of the gas passage at the position of the reduced diameter portion.

[0036] In some embodiments, the reduced diameter portion is located at the end of the gas passage away from the base body.

[0037] In some embodiments, the diameter of the reduced diameter portion is three-eighths to five-eighths of the diameter of the gas passage.

[0038] As another technical solution, the application also provides a semiconductor processing equipment, which comprises a process chamber and a bearing device arranged in the process chamber, and the bearing device adopts the above bearing device provided by the application.

[0039] The application has the following beneficial effects:

[0040] The carrier provided by the application has a susceptor body with a first surface and a second surface lower than a reference surface on which a wafer is carried, the first surface is close to the edge of the susceptor body, and the second surface is located in the central region of the susceptor body; the susceptor body also has a third surface located between the first surface and the second surface and recessed in a direction away from the reference surface. The third surface is located in the region (referred to as the inner ring region) between the edge region and the central region of the gas space formed between the susceptor body and the wafer; by recessing the third surface in a direction away from the reference surface, the volume of the inner ring region of the gas space can be increased, the increase in the volume helps to make the pressure distribution in the radial direction of the inner ring region more uniform, and the pressure in the central region can be increased, so that the pressure distribution uniformity of the inner ring region can be improved, and the pressure difference between the central region and the inner ring region of the gas space can be compensated, and the pressure distribution uniformity can be further improved. On this basis, the distances between the first surface, the second surface and the third surface and the reference surface can be adjusted according to the pressure distribution of different regions of the gas space, so as to change the volumes of the edge region, the central region and the inner ring region of the gas space, and the pressure difference between the edge region, the central region and the inner ring region of the gas space can be further compensated. At the same time, by distributing the gas passage structure connected in communication on the first surface, the second surface and the third surface, the volumes of the edge region, the central region and the inner ring region of the gas space can be further increased, and a way of adjusting the volume of the gas space is added, so that the pressure distribution of different diameters of the gas space can be more flexibly adjusted, the pressure distribution uniformity is further improved, the wafer temperature distribution uniformity is improved, and the process uniformity (such as film thickness uniformity) is improved.

[0041] The semiconductor processing equipment provided by the application can improve the pressure distribution uniformity, and further improve the wafer temperature distribution uniformity, so as to improve the process uniformity (such as film thickness uniformity). BRIEF DESCRIPTION OF DRAWINGS

[0042] FIG. 1 is a sectional view of a carrier of the prior art;

[0043] FIG. 2 is a comparison diagram of the pressure of different diameters of the susceptor body of the prior art and the embodiment of the application;

[0044] FIG. 3 is a simulation diagram of the pressure of different diameters of the susceptor body of the prior art;

[0045] FIG. 4 is a top view of the susceptor body adopted in the embodiment of the application;

[0046] FIG. 5 is a partial enlarged view of the susceptor body adopted in the embodiment of the application along line A-A in FIG. 4;

[0047] FIG. 6 is a perspective view of the susceptor body adopted in the embodiment of the application;

[0048] Fig. 7 is an enlarged view of region I in Fig. 6;

[0049] Fig. 8 is an enlarged view of region II in Fig. 6;

[0050] Fig. 9 is a simulation diagram of pressure distribution of a gas space of a susceptor body used in Fig. 6;

[0051] Fig. 10 is a structure top view of a susceptor body above the height of the bottom surface of a gas passage structure distributed on a first surface and a second surface;

[0052] Fig. 11 is a structure top view of a susceptor body below the height of a third surface;

[0053] Fig. 12 is a simulation diagram of pressure distribution of a gas space when a first surface and a second surface are distributed with a gas passage structure, and a third surface is recessed away from a reference surface, but is not distributed with a gas passage structure;

[0054] Fig. 13 is a simulation diagram of pressure distribution of a gas space when a third surface is reduced to a distance from a reference surface consistent with the distance of a first surface and a second surface from the reference surface, and the first surface, the second surface and the third surface are all provided with a gas passage structure, and the depth of the gas passage structure distributed on the third surface is greater than the depth of the gas passage structure distributed on the first surface and the second surface;

[0055] Fig. 14 is a comparison diagram of pressure distribution curves of the gas spaces in Fig. 12, Fig. 13 and Fig. 9;

[0056] Fig. 15 is a cross-sectional schematic view of a susceptor body and a susceptor shaft used in an embodiment of the present application;

[0057] Fig. 16 is a structure schematic view of a process chamber of a semiconductor processing apparatus used in an embodiment of the present application;

[0058] Fig. 17 is a comparison diagram of pressure distribution curves of gas spaces with and without a reduced diameter portion in an embodiment of the present application;

[0059] Fig. 18 is a comparison diagram of film thickness distribution curves of prior art and an embodiment of the present application. DETAILED DESCRIPTION

[0060] To enable those skilled in the art to better understand the technical solutions of the present application, the carrier device and the semiconductor processing apparatus provided by the present application are described in detail below with reference to the drawings.

[0061] Embodiments of the present application provide a carrier device, which is applied to a semiconductor processing equipment for example, and is used for being arranged in a process chamber of the semiconductor processing equipment and for carrying a wafer. In some embodiments, the carrier device is a vacuum chuck heater for example, which can not only fix the wafer, but also control the temperature of the wafer by heating (or cooling). Further, the carrier device fixes the wafer by vacuum adsorption for example, i.e. by using the pressure difference between the upper and lower surfaces of the wafer to fix the wafer.

[0062] As shown in FIG. 1, the carrier device in the related art includes a susceptor body 01, which is provided with an annular boss 011 at the top edge thereof, and the top surface 012 of the annular boss 011 is used for supporting the edge area of the bottom of a wafer 02. Further, a gas space 04 is formed between the top surface of the susceptor body 01 and the wafer 02 at the inner side of the annular boss 011. In addition, the top surface of the susceptor body 01 is further provided with a plurality of adsorption gas holes 03, which are in communication with the gas space 04, and the plurality of adsorption gas holes 03 are used for being connected with an external gas extraction device through a gas channel. When the gas extraction device works, the gas in the gas space 04 flows to each adsorption gas hole 03 close to the center of the susceptor body 01 and is extracted through each adsorption gas hole 03, so as to form a pressure difference between the upper and lower surfaces of the wafer 02, thereby fixing the wafer 02 to the susceptor body 01.

[0063] Further, as shown in curve 1 in FIG. 2 and FIG. 3, in the related art, the pressure distribution in the gas space 04 is that the pressure of the central region of the susceptor body 01 (the orthographic projection of each adsorption gas hole 03 on the susceptor body 01 is located within the boundary of the central region, for example, inscribed in the boundary of the central region, and the diameter of the boundary of the central region is 80 mm for example) is lower than that of other regions located outside the central region. Further, the pressure of the inner ring region of the gas space 04 between the edge region thereof and the above-mentioned central region (the outer peripheral diameter is 250 mm for example) sharply decreases from the outer periphery to the inner periphery in the radial direction, which leads to the non-uniform pressure distribution of the inner ring region, and also leads to the non-uniform pressure distribution between different regions of the gas space 04.

[0064] The inventors have found that the reason for the uneven pressure distribution is that the wafer edge is prone to warping under high temperature during the process, which causes external gas to directly enter the inner ring area of the gas space 04 from the gap between the wafer 02 and the top surface 012 of the annular boss 011. Since the distance between the top surface of the base body 01 in the related art and the wafer 02 in the gas space 04 is very small, the volume of the gas space 04 is limited, so the gas flowing into the inner ring area causes the pressure in the inner ring area to be higher near the outer periphery and lower near the inner periphery (affected by the adsorption pores 03), that is, the pressure sharply decreases from the outer periphery to the inner periphery in the radial direction, resulting in uneven pressure distribution in the inner ring area, and uneven pressure distribution between different areas of the gas space 04, which further leads to poor process uniformity (such as film thickness uniformity). As shown in curve 1 in FIG. 2, which is a curve of the pressure of the base body of different diameters in the related art, the pressure distribution uniformity of the gas space 04 in the related art can be calculated to be 20.17 according to the curve 1, and as shown in FIG. 3, which is a simulation diagram of the pressure distribution of the gas space 04 in the related art. As can be seen from the curve 1 in FIG. 2 and FIG. 3, the pressure distribution uniformity of the base body of different diameters in the related art is poor.

[0065] To solve the above problems, the embodiments of the present application provide a bearing device which can solve the problem of uneven pressure distribution between the wafer and the base body in the related art, thereby improving the process uniformity.

[0066] Specifically, referring to FIGS. 4-8, the bearing device provided by the embodiments of the present application includes a base body 1, and the plane on which the wafer 2 is located is the reference plane H0, as shown in FIG. 5. When the wafer 2 is placed on the base body 1, the bottom surface of the wafer 2 is flush with the reference plane H0. The base body 1 has an annular boss 14, the top surface of which is flush with the reference plane H0, which can be used as a sealing surface to support and seal the edge area of the wafer 2. Inside the annular boss 14, a gas space is formed between the wafer 2 and the base body 1, and the gas in the gas space can exchange heat between the wafer 2 and the base body 1 to achieve temperature control of the wafer. Moreover, by extracting part of the gas in the gas space, an air pressure difference can be generated between the upper and lower surfaces of the wafer to achieve vacuum adsorption to fix the wafer. For example, an adsorption gas hole 5 is arranged in the center area of the base body 1, which is connected to an external gas extraction device through a gas passage. When the gas extraction device is working, the gas in the gas space flows to the adsorption gas hole 5 and is extracted through each adsorption gas hole 5, thereby forming an air pressure difference between the upper and lower surfaces of the wafer 2.

[0067] On this basis, in view of the problem of uneven gas space pressure distribution between the wafer and the base body in the related art, the embodiments of the present application increase the volume of different regions in the gas space according to the pressure distribution in the gas space, so as to improve the uniformity of the gas space pressure distribution, thereby improving the uniformity of the wafer temperature distribution and improving the process uniformity (such as the film thickness uniformity).

[0068] Specifically, the base body 1 has a first surface 11 and a second surface 12, which are lower than the reference surface H0. The first surface 11 is close to the inner peripheral edge of the annular protrusion 14, i.e. located on the inner side of the annular protrusion 14, i.e. located on the edge region of the above-mentioned gas space. The second surface 12 is located in the central region of the base body 1, i.e. located in the central region of the above-mentioned gas space. The base body 1 also has a third surface 13 located between the first surface 11 and the second surface 12, which is recessed in the direction away from the reference surface H0. That is, the third surface 13 is located in the region between the edge region and the central region of the above-mentioned gas space (hereinafter referred to as the inner ring region).

[0069] Since the third surface 13 is recessed in the direction away from the reference surface H0, it makes the third surface 13 at each position lower than the first surface 11 and / or the second surface 12. It is easy to understand that if the first surface 11 and the second surface 12 are flush, the third surface 13 at each position (excluding the junction position of the third surface 13 with the first surface 11 and the second surface 12) is lower than the first surface 11 and the second surface 12; if the first surface 11 is higher than the second surface 12, the third surface 13 at each position is lower than the first surface 11, and part of the third surface 13 at each position is lower than the second surface 12, and another part is higher than the second surface 12. Conversely, if the second surface 12 is higher than the first surface 11, the third surface 13 at each position is lower than the second surface 12, and part of the third surface 13 at each position is lower than the first surface 11, and another part is higher than the first surface 11.

[0070] The third surface 13 is recessed away from the reference surface H0, which increases the volume of the inner annular region of the gas space. The increased volume allows the inner annular region to accommodate more gas when external gas flows in, so that more gas in the inner annular region flows to the central region along the gas flow, which helps to make the pressure distribution in the inner annular region more uniform in the radial direction, and increases the pressure in the central region. As a result, the pressure distribution uniformity in the inner annular region is improved, and the pressure difference between the central region and the inner annular region of the gas space is compensated, which further improves the pressure distribution uniformity. In addition, the distances between the first surface, the second surface, and the third surface and the reference surface can be adjusted to change the volumes of the edge region, the central region, and the inner annular region of the gas space, so that the pressure difference between the central region, the inner annular region, and the edge region of the gas space is further compensated, which further improves the pressure distribution uniformity.

[0071] In addition, the first surface 11, the second surface 12, and the third surface 13 are each provided with a gas channel structure. Specifically, the first surface 11, the second surface 12, and the third surface 13 are respectively provided with a first gas channel structure 41, a second gas channel structure 42, and a third gas channel structure 43, which are connected to each other. With the gas channel structure, the volumes of the edge region, the central region, and the inner annular region of the gas space are further increased, and a way of adjusting the volume of the gas space is provided, for example, adjusting the shape, depth, and width of the gas channel structure, which are related to the volume, to change the volume of the region where the gas channel structure is located, so that the pressure distribution of the gas space at different diameters can be more flexibly adjusted, the pressure distribution uniformity is further improved, the wafer temperature distribution uniformity is improved, and the process uniformity (for example, film thickness uniformity) is improved.

[0072] As shown in curve 2 in FIG. 2, which is a pressure distribution curve of the gas space in the embodiment of the present application, the pressure distribution uniformity of the gas space in the embodiment of the present application is calculated to be 6.12, which is significantly better than the pressure distribution uniformity (20.17) of the gas space 04 in the related art. In addition, FIG. 9 is a simulation diagram of the pressure distribution of the gas space in the embodiment of the present application. As can be seen from the comparison between FIG. 3 and FIG. 9, the pressure distribution uniformity of the gas space in the embodiment of the present application is better.

[0073] In some embodiments, the gas passage structure described above can be in communication with the adsorption gas hole 5, for sequentially guiding a portion of the gas in the gas space to the adsorption gas hole 5 along the first gas passage structure 41, the third gas passage structure 43 and the second gas passage structure 42 when the gas suction device is working. The shape and arrangement of the first gas passage structure 41, the second gas passage structure 42 and the third gas passage structure 43 can be set according to specific needs, and the embodiments of the present application do not have special limitations in this regard.

[0074] In some embodiments, in order to compensate for the pressure difference between the central region, the inner ring region and the edge region of the gas space, thereby improving the pressure distribution uniformity of the gas space of different diameters, the third surface 13 is a first annular surface surrounding the second surface 12; and the first surface 11 is a second annular surface surrounding the first annular surface. The first surface 11 and the third surface 13 are annular surfaces. In other embodiments, the third surface 13 can also be multiple and surround the second surface 12, which can also increase the space volume of the inner ring region to compensate for the pressure difference between the central region, the inner ring region and the edge region of the gas space. In this case, each third surface 13 can be any shape such as a circle, a polygon, etc., and the shapes of the multiple third surfaces 13 can be the same or different. In addition, in the case where the first surface 11 and the second surface 12 are not flush, the region of the inner ring region of the gas space other than the multiple third surfaces 13 can be flush with the first surface 11 or flush with the second surface 12; in the case where the first surface 11 and the second surface 12 are flush, the region of the inner ring region of the gas space other than the multiple third surfaces 13 can be flush with the first surface 11 and the second surface 12.

[0075] It should be noted that the shape and arrangement of the first gas passage structure 41, the second gas passage structure 42 and the third gas passage structure 43 can be set according to specific needs, and the embodiments of the present application do not have special limitations in this regard. In some embodiments, the gas passage structure 41 distributed on the first surface 11 (i.e. the second annular surface) includes an annular gas passage extending along the circumference of the second annular surface. The annular gas passage can uniformly guide the gas entering the gas space from the circumferential edge of the gas space to the gas passage structure 43 distributed on the third surface 13 (i.e. the first annular surface), thereby improving the gas distribution uniformity of the gas space in the circumferential direction, and further improving the pressure distribution uniformity of the gas space in the circumferential direction.

[0076] The second gas passage structure 42 and the third gas passage structure 43 are arranged between the annular gas passage and the adsorbing gas holes 5, and are, for example, a plurality of gas passage guides arranged in two parts on the second surface 12 and the third surface 13, respectively. The projections of the plurality of gas passage guides on the top of the base 1 are, for example, arranged in axial symmetry. The plurality of gas passage guides are arranged to split and combine the gas flowing therethrough, so as to improve the uniformity of the gas distribution. The number and arrangement of the plurality of gas passage guides for achieving the above functions can be set according to specific needs, and the embodiments of the present application do not have special limitations thereon.

[0077] In some embodiments, the third surface 13 (i.e., the first annular surface) can be an arc surface or a stepped surface. The concave depth of the arc surface decreases, for example, from the outer peripheral edge and the inner peripheral edge of the first annular surface towards the middle. The concave depth is the distance of the concave towards the direction away from the reference surface H0. The stepped surface is composed of a plurality of levels of planes with height differences, and the distance of the plurality of levels of planes from the reference surface H0 increases, for example, from the outer peripheral edge and the inner peripheral edge of the first annular surface towards the middle, that is, for each two adjacent levels of planes, the level of plane closer to the middle is lower than the level of plane farther from the middle. Of course, the distribution of the concave depth of the arc surface and the height distribution of the plurality of levels of planes of the stepped surface are not limited to the distribution of the above embodiments, and in actual applications, the distribution can be set according to the pressure difference between the central region, the inner ring region and the edge region of the gas space.

[0078] In some embodiments, in order to compensate for the pressure difference between the central region, the inner ring region and the edge region of the gas space, so as to improve the uniformity of the pressure distribution of different diameters of the gas space, the first surface 11 (i.e., the second annular surface) can be a plane, which can be parallel to the horizontal plane, or inclined relative to the horizontal plane, for example, inclined downward from the outer peripheral edge to the inner peripheral edge of the second annular surface, in which case the outer peripheral edge of the second annular surface can be flush with the reference surface H0, and the distance of the second annular surface from the reference surface H0 increases from the outer peripheral edge to the inner peripheral edge.

[0079] In some embodiments, in order to further increase the pressure of the central region of the gas space, the second surface 12 can be a plane, which can be parallel to the horizontal plane, that is, the distance of the second surface 12 from the reference surface H0 is equal everywhere.

[0080] In some embodiments, the third surface 13 (i.e. the first annular surface) and the first surface 11 (i.e. the second annular surface) are both circular annular surfaces; and the second surface 12 is a circular surface. Further, the boundaries of the first surface 11, the third surface 13 and the second surface 12 coincide, i.e. the outer peripheral boundary of the first surface 11 is the circumference of the circle where the K1 line is located, and further, in some embodiments, the inner peripheral boundary of the annular protrusion 14 coincides with the outer peripheral boundary of the first surface 11. The inner peripheral boundary of the first surface 11 and the outer peripheral boundary of the third surface 13 coincide, i.e. the circumference of the circle where the K2 line is located. The inner peripheral boundary of the third surface 13 and the outer peripheral boundary of the second surface 12 coincide, i.e. the circumference of the circle where the K3 line is located. In this case, the inner peripheral diameter of the first surface 11 (i.e. the second annular surface) is equal to the outer peripheral diameter of the third surface 13 (i.e. the first annular surface); and the inner peripheral diameter of the third surface 13 (i.e. the first annular surface) is equal to the outer peripheral diameter of the second surface 12. By making the third surface 13 and the first surface 11 adopt circular annular surfaces, and the second surface 12 adopt a circular surface, the volume of the gas space can be ensured to be consistent on the circumference of the same diameter, so as to improve the uniformity of the pressure distribution in the circumferential direction of the gas space. Of course, in actual applications, the inner peripheral edge shape (i.e. the outer peripheral edge shape of the second surface 12) and the outer peripheral edge shape (i.e. the inner peripheral edge shape of the first surface 11) of the third surface 13 (i.e. the first annular surface) can also be designed according to the pressure distribution of the gas space in the circumferential direction, and the radial distance of the inner peripheral edge shape and the outer peripheral edge shape from the center of the gas space in the circumferential direction is different, i.e. a non-circular edge. For example, an elliptical edge or a special-shaped edge, etc.

[0081] In some embodiments, a plurality of adsorption air holes 5 are formed in the second surface 12 (i.e. the circular surface) and are in communication with the gas passage structure 42, the centers of the plurality of adsorption air holes 5 are distributed on the circumference with the center of the second surface 12 as the center, and the diameter of the circumference where the plurality of adsorption air holes 5 are located is smaller than the outer peripheral diameter of the second surface 12. Further, in some embodiments, the plurality of adsorption air holes 5 are uniformly distributed along the circumferential direction of the second surface 12, so as to improve the uniformity of the gas distribution in the circumferential direction of the gas space, and further improve the uniformity of the pressure distribution in the circumferential direction of the gas space.

[0082] In some embodiments, in order to improve the pressure in the central region of the gas space and reduce the pressure difference between the central region and the inner ring region of the gas space, the outer peripheral diameter of the second surface 12 can be set according to the diameter of the circumference where the plurality of adsorption air holes 5 are located, specifically, the ratio of the outer peripheral diameter of the second surface 12 to the diameter of the circumference where the centers of the adsorption air holes 5 are located is greater than or equal to 1.2 and less than or equal to 1.8.

[0083] In some embodiments, the outer peripheral diameter of the second surface 12 is greater than or equal to 80 mm and less than or equal to 120 mm, for example, when the maximum outer diameter of the susceptor body 1 is 300 mm (or 12 inches).

[0084] In some embodiments, in order to reduce the pressure difference between the edge region, the center region and the inner ring region of the gas space, the outer peripheral diameter of the first surface 11 (i.e., the second annular surface) and / or the inner peripheral diameter of the first surface 11 (i.e., the second annular surface) can be determined according to the outer peripheral diameter of the second surface 12. Specifically, the ratio of the outer peripheral diameter of the first surface 11 (i.e., the second annular surface) to the outer peripheral diameter of the second surface 12 is greater than or equal to 2.35 and less than or equal to 3.73; the ratio of the inner peripheral diameter of the first surface 11 (i.e., the second annular surface) to the outer peripheral diameter of the second surface 12 is greater than or equal to 2.16 and less than or equal to 3.48. Of course, in actual applications, the outer peripheral diameter of the first surface 11 (i.e., the second annular surface) and / or the inner peripheral diameter of the first surface 11 (i.e., the second annular surface) can also be determined according to the ratio of the maximum outer diameter of the susceptor body 1 to the outer peripheral diameter of the first surface 11 (i.e., the second annular surface), the ratio of the maximum outer diameter of the susceptor body 1 to the inner peripheral diameter of the first surface 11 (i.e., the second annular surface), and the maximum outer diameter of the susceptor body 1 currently used. In some embodiments, the ratio of the maximum outer diameter of the susceptor body 1 to the outer peripheral diameter of the first surface 11 (i.e., the second annular surface) is greater than or equal to 1.01 and less than or equal to 1.06, for example; the ratio of the maximum outer diameter of the susceptor body 1 to the inner peripheral diameter of the first surface 11 (i.e., the second annular surface) is greater than or equal to 1.16 and less than or equal to 1.08, for example. When the maximum outer diameter of the susceptor body 1 is 300 mm (or 12 inches), for example, the outer peripheral diameter of the first surface 11 (i.e., the second annular surface) is greater than or equal to 282 mm and less than or equal to 298 mm; the inner peripheral diameter of the first surface 11 (i.e., the second annular surface) is greater than or equal to 259 mm and less than or equal to 279 mm.

[0085] In some embodiments, in order to increase the volume of the inner ring region of the gas space while improving the pressure distribution uniformity of the inner ring region and the center region of the gas space, the distance between the third surface 13 and the reference surface H0 is 4.5 times to 15 times the distance between the second surface 12 and the reference surface H0. For example, 4.5 times, 5.5 times, 6 times, 6.5 times, 7 times, 7.5 times, 8 times, 8.5 times, 9 times, 9.5 times, 10 times, 10.5 times, 11 times, 11.5 times, 12 times and 15 times, preferably 5 times.

[0086] In some embodiments, in order to increase the volume of the inner ring region of the gas space while improving the pressure distribution uniformity of the inner ring region and the edge region of the gas space, the distance between the third surface 13 and the reference surface H0 is 4.5 to 15 times the distance between the first surface 11 and the reference surface H0. For example, 4.5 times, 5.5 times, 6 times, 6.5 times, 7 times, 7.5 times, 8 times, 8.5 times, 9 times, 9.5 times, 10 times, 10.5 times, 11 times, 11.5 times, 12 times, and 15 times, preferably 5 times.

[0087] In some embodiments, in order to further increase the pressure of the central region of the gas space, the distance between the second surface 12 and the reference surface H0 is less than or equal to the distance between the first surface 11 and the reference surface H0. For example, in the case where the distance between the second surface 12 and the reference surface H0 is equal to the distance between the first surface 11 and the reference surface H0, FIG. 10 shows the structure of the susceptor body 1 above the height of the gas channel bottom surface of the gas channel structure distributed by the first surface 11, and the gas channel structure distributed by the third surface 13 is below this height, which is not shown in FIG. 10. As can be seen from FIG. 10, the gas entering the gas space is first uniformly guided to the inner ring region where the third surface 13 (i.e. the first annular surface) is located via the first gas channel structure 41 (annular gas channel) distributed on the first surface 11. Since the third surface 13 is recessed in the direction away from the reference surface H0, the volume of the space between the third surface 13 and the wafer is large, which helps to make the pressure distribution in the radial direction of the inner ring region more uniform, and can also increase the pressure of the central region, so as to not only improve the pressure distribution uniformity of the inner ring region, but also compensate for the pressure difference between the central region and the inner ring region of the gas space, thereby improving the pressure distribution uniformity. FIG. 11 shows the structure of the susceptor body 1 below the height of the third surface 13, and the first surface 11 and the second surface 12 and the gas channel structure distributed thereby are above this height, which is not shown in FIG. 11.

[0088] It is found through simulation experiments that, as shown in FIGS. 12-14, FIG. 12 is a simulation diagram of pressure distribution of the gas space when the first surface and the second surface are distributed with the air channel structure, and the third surface is recessed away from the reference surface but is not distributed with the air channel structure. FIG. 13 is a simulation diagram of pressure distribution of the gas space when the distance between the third surface and the reference surface is reduced to be consistent with the distance between the first surface and the second surface and the reference surface, and the first surface 11, the second surface 12 and the third surface 13 are all provided with the air channel structure, and the depth of the air channel structure distributed on the third surface 13 is greater than the depth of the air channel structure distributed on the first surface 11 and the second surface 12. Curve 1 in FIG. 14 is the pressure distribution curve of the gas space in FIG. 13; curve 2 in FIG. 14 is the pressure distribution curve of the gas space in FIG. 12; and curve 3 in FIG. 14 is the pressure distribution curve of the gas space in FIG. 7. Comparing the curves 1, 2 and 3, it can be seen that, in the case that the third surface 13 is recessed away from the reference surface H0, and the first surface 11, the second surface 12 and the third surface 13 are all provided with the air channel structure, the pressure distribution uniformity of the gas space is the best.

[0089] In some embodiments, the distance between the second surface 12 and the reference surface H0 is greater than 0 μm and less than or equal to 50 μm.

[0090] In some embodiments, the distance between the first surface 11 and the reference surface H0 is greater than 0 μm and less than or equal to 50 μm.

[0091] In some embodiments, the difference between the distance between the third surface 13 and the reference surface H0 and the distance between the second surface 12 and the reference surface H0 is greater than or equal to 60 μm and less than or equal to 140 μm.

[0092] In some embodiments, the difference between the distance between the third surface 13 and the reference surface H0 and the distance between the first surface 11 and the reference surface H0 is greater than or equal to 60 μm and less than or equal to 140 μm.

[0093] In some embodiments, the air channel structures distributed on the first surface 11, the second surface 12 and the third surface 13 are respectively the first air channel structure 41, the second air channel structure 42 and the third air channel structure 43, and the depths of the air channel structures are the same. Of course, in actual applications, according to the specific needs of adjusting the volume of the gas space, at least two of the depths of the first air channel structure 41, the second air channel structure 42 and the third air channel structure 43 can be different.

[0094] In some embodiments, the depths of the air channel structures distributed on the first surface 11, the second surface 12 and the third surface 13 are greater than or equal to 60 μm and less than or equal to 140 μm.

[0095] In some embodiments, the second surface 12 and the third surface 13 are both provided with a plurality of protrusions 3, and the top surface of each protrusion 3 is flush with the reference surface H0, for supporting the wafer 2. By supporting the wafer 2 with the plurality of protrusions 3, the contact area between the susceptor body 1 and the wafer 2 can be reduced, so that the metal ion contamination caused by the contact between the susceptor body 1 and the wafer 2 can be reduced. Specifically, the protrusions 3 are, for example, in the shape of columns, the bottom end of each protrusion 3 is connected to, for example, integrated with, the second surface 12 or the third surface 13, the top surface of each protrusion 3 is in contact with the wafer 2 for supporting the wafer 2, and the top surfaces of all the protrusions 3 are flush with each other to ensure the levelness of the wafer 2.

[0096] The protrusions distributed on the third surface 13 are first protrusions 3a, and the protrusions distributed on the second surface 12 are second protrusions 3b. The total horizontal cross-sectional area of the plurality of second protrusions 3b accounts for a percentage of the area of the second surface 12, which is greater than the total horizontal cross-sectional area of the plurality of first protrusions 3a accounts for a percentage of the area of the second surface 12. That is, the distribution density of the plurality of second protrusions 3b is greater than the density of the plurality of first protrusions 3a, which can further increase the volume of the inner ring area of the gas space, and at the same time, can increase the pressure of the central area, so as to improve the uniformity of the pressure distribution of the inner ring area and the central area of the gas space. In some embodiments, the total horizontal cross-sectional area of the plurality of protrusions (i.e., the first protrusions 3a) on the third surface 13 accounts for a percentage of the area of the second surface 12, which is greater than or equal to 0.8% and less than or equal to 2%; and the total horizontal cross-sectional area of the plurality of protrusions (i.e., the second protrusions 3b) on the second surface 12 accounts for a percentage of the area of the second surface 12, which is greater than or equal to 1% and less than or equal to 2.2%.

[0097] In some embodiments, the volume of the inner ring area of the gas space is further increased, and at the same time, the pressure of the central area is increased, so as to improve the uniformity of the pressure distribution of the inner ring area and the central area of the gas space. The plurality of protrusions 3 on the second surface 12 (i.e., the circular surface) and the third surface 13 (i.e., the first annular surface) are both distributed at least one circle along the circumference of the susceptor body 1; and the distance between adjacent protrusions (i.e., the second protrusions 3b) on the same circle on the second surface 12 is less than the distance between adjacent protrusions (i.e., the first protrusions 3a) on the same circle on the third surface 13; and / or the radial distance between the circumferences where the adjacent two circles of protrusions (i.e., the second protrusions 3b) on the second surface 12 are located is less than the radial distance between the circumferences where the adjacent two circles of protrusions (i.e., the first protrusions 3a) on the third surface 13 are located.

[0098] In some embodiments, as shown in FIGS. 15 and 16, the bearing device further comprises a base shaft 7 arranged at the bottom of the base body 1, which is used to drive the base body 1 to move up and down, for example. The base shaft 7 is provided with a gas passage 51, one end of the gas passage 51 is communicated with each adsorption gas hole 5, and the other end of the gas passage 51 is used to be communicated with a gas extraction device 61. The gas extraction device is a molecular pump, for example. When the gas extraction device 61 works, the gas in the gas space flows to the adsorption gas hole 5, and is sequentially extracted through each adsorption gas hole 5 and the gas passage 51, so as to form a gas pressure difference between the upper and lower surfaces of the wafer 2. In a specific example, the other end of the gas passage 51 is connected with the gas extraction device 61 through a gas pipeline, and a pressure controller 62 is further connected on the gas pipeline, which is used to control the pressure in the gas passage 51 to be less than the chamber pressure in the process chamber 100, so as to form a gas pressure difference between the upper and lower surfaces of the wafer 2, thereby achieving the vacuum adsorption and fixation of the wafer. For example, if the chamber pressure is 3 Torr, the pressure in the gas passage 51 is 2 Torr.

[0099] Further, the gas passage 51 is provided with a reduced diameter portion 8, which is used to reduce the gas passage area of the gas passage 51 at the position where the reduced diameter portion 8 is located. In this way, the reduced diameter portion 8 and the gas passage between the gas inlet end of the adsorption gas hole 5 can produce a gas choking, which not only can further increase the pressure in the central region of the gas space compared with the gas passage without the reduced diameter portion 8, but also can reduce the pressure fluctuation of the gas passage between the reduced diameter portion 8 and the gas inlet end of the adsorption gas hole 5 caused by the fluctuation of the chamber pressure and the pressure fluctuation generated by the pressure controller 62 in the pressure control process, that is, improve the pressure stability of the gas space, so as to avoid the problem that the instantaneous pressure in the gas space is greater than the chamber pressure due to the pressure fluctuation, thereby causing the wafer to deviate. That is, the existence of the reduced diameter portion 8 can reduce the pressure fluctuation in the gas passage between the reduced diameter portion 8 and the gas inlet end of the adsorption gas hole 5, and improve the pressure stability of the gas space.

[0100] As shown in FIG. 17, curve 1 is the gas space pressure distribution curve of the embodiment of the present application without the reduced diameter portion 8, and curve 2 is the gas space pressure distribution curve of the embodiment of the present application with the reduced diameter portion 8. As can be seen from the comparison between curve 1 and curve 2, the gas space pressure distribution uniformity is better when the reduced diameter portion 8 is arranged. On this basis, as shown in FIG. 18, curve 1 is the film thickness distribution curve of the related art, and according to the curve 1, the film thickness distribution uniformity of the related art is calculated to be 1.19, and curve 2 is the film thickness distribution curve of the embodiment of the present application, and according to the curve 2, the film thickness distribution uniformity of the embodiment of the present application is calculated to be 0.36. Therefore, it can be seen that the film thickness uniformity of the embodiment of the present application is obviously better than that of the related art.

[0101] In some embodiments, the reduced diameter portion 8 is located at an end of the gas passage 51 away from the susceptor body 1. In this way, the reduced diameter portion 8 is located away from the susceptor body 1 so that the gas flow in the vicinity of the gas space is relatively stable, thereby avoiding disturbance to the local gas flow field due to gas flow fluctuations at the location of the reduced diameter portion 8.

[0102] In some preferred embodiments, in order to effectively increase the pressure of the central region of the gas space, the pressure stability of the gas space, the diameter of the reduced diameter portion 8 is three-eighths to five-eighths of the diameter of the gas passage 51.

[0103] As another technical solution, the embodiments of the present application also provide a semiconductor processing equipment, which comprises a process chamber and a carrying device arranged in the process chamber, and the carrying device adopts the above-mentioned carrying device provided by the embodiments of the present application.

[0104] The semiconductor processing equipment provided by the embodiments of the present application can improve the pressure distribution uniformity by adopting the carrying device provided by the embodiments of the present application, and further can improve the wafer temperature distribution uniformity, thereby improving the process uniformity (for example, the film thickness uniformity).

[0105] It can be understood that the above embodiments are only exemplary embodiments for illustrating the principles of the present application, and the present application is not limited thereto. Various modifications and improvements can be made by those skilled in the art without departing from the spirit and essence of the present application, and these modifications and improvements are also considered as the protection scope of the present application.

Claims

1. A load bearing device, characterized by, The base body carries a wafer plane as a reference surface, and has a ring-shaped convex part with a top surface flush with the reference surface for supporting and sealing the edge region of the wafer; the base body also has a first surface and a second surface lower than the reference surface, the first surface is close to the inner peripheral edge of the ring-shaped convex part, and the second surface is located in the central region of the base body; the base body also has a third surface located between the first surface and the second surface and recessed away from the reference surface; The first surface, the second surface and the third surface are all distributed with air channel structures connected thereto.

2. The load bearing device of claim 1, wherein, The third surface is a first annular surface surrounding the second surface; or the third surface is a plurality of surfaces surrounding the second surface. The first surface is a second annular surface surrounding the first annular surface.

3. The load bearing device of claim 2, wherein, The third surface is an arc surface or a stepped surface.

4. The load bearing device of claim 2, wherein, The first annular surface and the second annular surface are both circular annular surfaces; the second surface is a circular surface; The inner peripheral diameter of the second annular surface is equal to the outer peripheral diameter of the first annular surface; the inner peripheral diameter of the first annular surface is equal to the outer peripheral diameter of the second surface.

5. The load bearing device of claim 2, wherein, The air channel structure distributed on the second annular surface includes an annular air channel extending along the circumferential direction of the second annular surface.

6. The load bearing device of claim 4, wherein, A plurality of adsorption air holes are formed in the second surface and connected to the air channel structure, and the centers of the plurality of adsorption air holes are distributed on a circle with the center of the second surface as the center.

7. The load bearing device of claim 6, wherein, The ratio of the outer peripheral diameter of the second surface to the diameter of the circle on which the centers of the adsorption air holes are distributed is greater than or equal to 1.2 and less than or equal to 1.

8.

8. The load bearing device of claim 4, wherein, The ratio of the outer peripheral diameter of the second annular surface to the outer peripheral diameter of the second surface is greater than or equal to 2.35 and less than or equal to 3.73; the ratio of the inner peripheral diameter of the second annular surface to the outer peripheral diameter of the second surface is greater than or equal to 2.16 and less than or equal to 3.

48.

9. The load bearing device of claim 4, wherein, The outer peripheral diameter of the second annular surface is greater than or equal to 282 mm and less than or equal to 298 mm; the inner peripheral diameter of the second annular surface is greater than or equal to 259 mm and less than or equal to 279 mm.

10. The load bearing device of claim 4, wherein, The outer peripheral diameter of the second surface is greater than or equal to 80 mm and less than or equal to 120 mm.

11. The load bearing device of any of claims 1-10, wherein, The distance between the third surface and the reference surface is 4.5 to 15 times the distance between the second surface and the reference surface; and / or, The distance between the third surface and the reference surface is 4.5 to 15 times the distance between the first surface and the reference surface.

12. The load bearing device of any of claims 1-10, wherein, The distance between the second surface and the reference surface is less than or equal to the distance between the first surface and the reference surface.

13. The load bearing device of any of claims 1-10, wherein, The distance between the second surface and the reference surface is greater than 0 μm and less than or equal to 50 μm; and / or, The distance between the first surface and the reference surface is greater than 0 μm and less than or equal to 50 μm.

14. The load bearing device of any one of claims 1-10, wherein, The difference between the distance between the third surface and the reference surface and the distance between the second surface and the reference surface is greater than or equal to 60 μm and less than or equal to 140 μm. And / or, The difference between the distance between the third surface and the reference surface and the distance between the first surface and the reference surface is greater than or equal to 60 μm and less than or equal to 140 μm.

15. The load bearing device of any of claims 1-10, wherein, The depth of the airway structure where the first surface, the second surface and the third surface are distributed is the same.

16. The load bearing device of claim 15, wherein, The depth of the airway structure where the first surface, the second surface and the third surface are distributed is greater than or equal to 60 μm and less than or equal to 140 μm.

17. The load bearing device of any one of claims 1-10, wherein, A plurality of protrusions are distributed on the second surface and the third surface, and the top surface of each protrusion is flush with the reference surface, for supporting a wafer; The percentage of the total horizontal cross-sectional area of the protrusions on the second surface to the area of the second surface is greater than the percentage of the total horizontal cross-sectional area of the protrusions on the third surface to the area of the second surface.

18. The load bearing device of claim 17, wherein, The percentage of the total horizontal cross-sectional area of the protrusions on the third surface to the area of the second surface is greater than or equal to 0.8% and less than or equal to 2%. The percentage of the total horizontal cross-sectional area of the protrusions on the second surface to the area of the second surface is greater than or equal to 1% and less than or equal to 2.2%.

19. The load bearing device of claim 4, wherein, A plurality of protrusions are distributed on the second surface and the third surface, and the top surface of each protrusion is flush with the reference surface, for supporting a wafer; The protrusions on the second surface and the third surface are distributed in at least one circle along the circumference of the base body; The distance between adjacent protrusions in the same circle on the second surface is less than the distance between adjacent protrusions in the same circle on the third surface; and / or, the radial distance between the circumferences where two adjacent circles of protrusions are located on the second surface is less than the radial distance between the circumferences where two adjacent circles of protrusions are located on the third surface.

20. The load bearing device of any one of claims 1-10, wherein, A plurality of adsorption air holes are formed on the second surface and communicate with the airway structure, and the supporting device further comprises a base shaft arranged at the bottom of the base body, wherein a gas passage is arranged in the base shaft, one end of the gas passage communicates with the adsorption air hole, and the other end of the gas passage is used to communicate with a gas extraction device; A reduced diameter portion is arranged in the gas passage, and the reduced diameter portion is used to reduce the air passage cross-sectional area of the gas passage at the position where the reduced diameter portion is located.

21. The load bearing device of claim 20, wherein, The reduced diameter portion is located at the end of the gas passage away from the base body.

22. The load bearing device of claim 20, wherein, The diameter of the reduced diameter portion is three-eighths to five-eighths of the diameter of the gas passage.

23. A semiconductor processing apparatus comprising a process chamber and a carrier device disposed in the process chamber, characterized in that, The supporting device adopts the supporting device as claimed in any one of claims 1-22.

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