Support structures for epitaxial growth equipment, epitaxial growth equipment, and epitaxial wafers.

Abstract

This application relates to a support structure for an epitaxial growth apparatus, the epitaxial growth apparatus, and an epitaxial wafer. The support structure for the epitaxial growth apparatus includes a plurality of first support arms for supporting a base below a pedestal of the epitaxial growth apparatus for supporting a wafer thereon; and a plurality of second support arms, which are vertically movable and used to support the wafer from below. The plurality of second support arms are disposed above the plurality of first support arms and correspond to the plurality of first support arms in the vertical direction, and the second support arms are movable to contact the corresponding first support arm along the entire longitudinal length of the second support arm.

Description

Technical Field

[0001] This application claims priority to Chinese Patent Application No. 202410964402.7 filed in China on July 18, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the field of wafer epitaxial growth technology, and in particular, to a support structure for epitaxial growth equipment, epitaxial growth equipment, and an epitaxial wafer. Prior Art

[0003] Epitaxial growth process usually refers to the process of growing an epitaxial film on a substrate wafer by chemical vapor deposition to obtain an epitaxial wafer. Epitaxial wafers have the characteristics of few surface defects, excellent crystallinity and controllable resistivity. The epitaxial growth process is usually carried out in an epitaxial furnace. During the epitaxial growth process, the substrate wafer to be grown epitaxially is first carried on a pedestal in the reaction chamber of the epitaxial furnace, and then the raw material gas is introduced into the process chamber. Under the high temperature environment in the epitaxial furnace, the raw material gas flows through the surface of the substrate wafer and forms an epitaxial film thereon.

[0004] As an important parameter to measure the electrical properties of epitaxial wafers, resistivity is closely related to the epitaxial growth process conditions, especially the temperature conditions in the epitaxial furnace. However, due to the internal structural design of the epitaxial furnace and other reasons, the thermal field environment in the epitaxial furnace may have uneven temperature distribution, causing the substrate wafer to be heated unevenly as a whole, which in turn leads to poor uniformity of resistivity of the entire epitaxial wafer, which has an adverse effect on the quality of the epitaxial wafer. Summary of the invention

[0005] This section provides a general summary of the application, and is not a comprehensive disclosure of its full scope or all of its features.

[0006] The purpose of the present application is to provide a support structure for epitaxial growth equipment and an epitaxial growth equipment capable of improving the overall heating uniformity of a wafer.

[0007] The purpose of the present application is to provide a support structure for epitaxial growth equipment and an epitaxial growth equipment capable of improving the resistivity uniformity of epitaxial wafers.

[0008] In order to achieve the above-mentioned purpose, according to a first aspect of the present application, a support structure for an epitaxial growth device is provided, comprising:

[0009] a plurality of first support arms for supporting a susceptor from below a susceptor of an epitaxial growth apparatus for supporting a wafer thereon; and

[0010] A plurality of second support arms are provided, the plurality of second support arms being able to move in a vertical direction and being used to support the wafer from below the wafer, the plurality of second support arms being arranged above the plurality of first support arms and corresponding to the plurality of first support arms in a vertical direction, and the second support arms being able to move to contact the corresponding first support arms over the entire longitudinal length of the second support arms.

[0011] In some embodiments, each first support arm may include a first arcuate surface, each second support arm may include a second arcuate surface, and when the first support arm comes into contact with the corresponding second support arm, the first arcuate surface cooperates with the second arcuate surface to form a cylindrical surface.

[0012] In some embodiments, one of the first support arm and the corresponding second support arm may include a convex portion, and the other may include a concave portion, and the first support arm and the corresponding second support arm can form contact through the cooperation of the convex portion and the concave portion.

[0013] In some embodiments, each second supporting arm may include an arm portion and a pin portion, wherein the pin portion is formed integrally with the arm portion and extends in a vertical direction to provide support for the wafer.

[0014] In some embodiments, the support structure for the epitaxial growth device may also include a driving member, which is used to drive the multiple second support arms so that the multiple second support arms apply a downward force in a vertical direction to the multiple first support arms when the multiple second support arms come into contact with the multiple first support arms, wherein the force is greater than the gravity of the multiple second support arms.

[0015] In some embodiments, the second support arm can be a solid structure.

[0016] In some embodiments, the support structure for the epitaxial growth equipment may also include a first support column and a second support column, a plurality of first support arms extend toward the epitaxial growth with the first support column as the center, a plurality of second support arms extend toward the epitaxial growth with the second support column as the center, the first support column and the second support column both extend in the vertical direction, and the second support column is coaxially arranged inside the first support column in a liftable manner.

[0017] In some embodiments, the support structure for the epitaxial growth device may further include a retaining member configured to keep the relative positions of the first support column and the second support column fixed in the horizontal direction.

[0018] In some embodiments, the retaining member may be a rolling bearing disposed between the first support column and the second support column and in contact with the first support column and the second support column in a horizontal direction.

[0019] According to a second aspect of the present application, there is provided an epitaxial growth device, comprising:

[0020] a susceptor for supporting the wafer thereon; and

[0021] A support structure for an epitaxial growth device according to a first aspect of the present application.

[0022] According to a third aspect of the present application, an epitaxial wafer is provided. The epitaxial wafer is obtained using the epitaxial growth device according to the second aspect of the present application. The uniformity value of the epitaxial wafer is less than 4.08%, and the uniformity value is the ratio of the difference between the maximum value and the minimum value of the resistivity measured at multiple points on the diameter of the epitaxial wafer to the sum of the maximum value and the minimum value.

[0023] In some embodiments, the uniformity value of the epitaxial wafer can be less than 3%.

[0024] According to the above technical solution, by using the first support arm to shield the second support arm on the side away from the lower heat source, the second support arm is prevented from blocking the propagation path of part of the radiant heat, thereby improving the overall heating uniformity of the wafer, and further improving the resistivity uniformity of the epitaxial wafer. In addition, by making the first support arm contact with the second support arm to eliminate the gap between the two, the adverse effect of the gap on heat transfer is effectively avoided, so that the radiant heat is transferred to the wafer with less obstruction and loss, thereby further improving the overall heating uniformity of the wafer and the resistivity uniformity of the epitaxial wafer. Simple diagram description

[0025] The features and advantages of the embodiments of the present application will become more easily understood through the following description with reference to the accompanying drawings. The drawings are not drawn to scale, and some features may be enlarged or reduced to show the details of specific components. In the drawings:

[0026] FIG. 1 is a schematic diagram showing an epitaxial growth apparatus according to the related art.

[0027] FIG. 2 shows a resistivity distribution diagram of an epitaxial wafer obtained using the epitaxial growth apparatus of FIG. 1 .

[0028] FIG. 3 shows a radial resistivity variation curve of an epitaxial wafer obtained by using the epitaxial growth apparatus of FIG. 1 .

[0029] FIG. 4 is a schematic diagram showing a support structure for an epitaxial growth device according to an embodiment of the present application.

[0030] FIG5 shows a partial schematic diagram of the first support arm and the second support arm in a contact state according to an embodiment of the present application.

[0031] FIG6 shows a partial schematic diagram of the first support arm and the second support arm in a non-contact state according to an embodiment of the present application.

[0032] FIG. 7 shows a cross-sectional view of the first support arm and the second support arm in a contact state according to an embodiment of the present application, taken along the dashed line AA of FIG. 5 .

[0033] FIG8 shows a cross-sectional view of the first support arm and the second support arm in a contact state according to another embodiment of the present application, taken along the dotted line AA of FIG5 .

[0034] FIG. 9 shows a cross-sectional view of a first support arm and a second support arm in a non-contact state according to another embodiment of the present application, taken along the dotted line BB of FIG. 6 .

[0035] FIG. 10 shows a schematic diagram of an epitaxial growth apparatus according to an embodiment of the present application.

[0036] FIG. 11 is a diagram showing a comparison of a radial resistivity variation curve of an epitaxial wafer obtained using the epitaxial growth apparatus of FIG. 1 and a radial resistivity variation curve of an epitaxial wafer obtained using the epitaxial growth apparatus according to an embodiment of the present application.

[0037] In the drawings, the same or corresponding technical features or components are represented by the same or corresponding reference numerals. Implementation

[0038] The present application is described in detail below with reference to the accompanying drawings and by means of exemplary embodiments. It should be noted that the following detailed description of the present application is only for illustrative purposes and is by no means a limitation of the present application.

[0039] First, in conjunction with Figures 1 to 3, the problems in the background technology of this application are explained in detail.

[0040] FIG. 1 shows an epitaxial growth device 1 according to the related art. The epitaxial growth device 1 includes: an upper quartz bell 2 and a lower quartz bell 3, which basically define a reaction chamber for epitaxial growth; an air inlet 4 and an air outlet 5, which are respectively used to allow process gas to enter and leave the reaction chamber; an upper lamp group 6 and a lower lamp group 7, which are used as heat sources to provide the high temperature required for epitaxial growth; a base 8, which is used to carry a wafer; and a support structure 9, which is used to support the base 8 and drive the base 8 to rotate during the epitaxial growth process. The support structure 9 includes a base support part 91 for supporting the base 8, a lifting pin 92 for supporting the wafer, and a lifting pin support part 93 for supporting the lifting pin 92. The lifting pin support part 93 is located below the base support part 91 and can move up and down so as to drive the lifting pin 92 to move up and down.

[0041] When preparing for the epitaxial growth process, first, the wafer is transferred into the reaction chamber and is contacted and supported by the lifting pins 92 in the ascending position. Then, as the lifting pins 92 move to the descending position, the wafer is carried on the pedestal 8. After the wafer is carried in place, the process gas is introduced into the reaction chamber from the gas inlet 4, and the upper lamp group 6 and the lower lamp group 7 are used for heating. The support structure 9 drives the pedestal 8 and the wafer to rotate so that the process gas flows evenly over the surface of the wafer and epitaxial growth is performed.

[0042] FIG2 shows a resistivity distribution diagram of an epitaxial wafer with a diameter of 300 mm obtained by using the above-mentioned epitaxial growth apparatus 1. As shown in the figure, there is a significant color difference between the annular area about R / 2 from the center of the epitaxial wafer and other areas, which indicates that the resistivity of the entire epitaxial wafer in different areas is not uniform. The annular area corresponds to the area shielded by the lifting pin support portion 93.

[0043] FIG3 shows a radial resistivity variation curve of an epitaxial wafer with a diameter of 300 mm obtained by using the above-mentioned epitaxial growth device 1, wherein the abscissa represents the diameter and the ordinate represents the resistivity. As shown in the figure, the resistivity is relatively high in the region about R / 2 from the center of the epitaxial wafer (especially the diameter of -100 mm to 100 mm), which corresponds to the region shielded by the lifting pin support portion 93.

[0044] The reasons for the above-mentioned uneven resistivity problem of epitaxial wafers are analyzed in detail below.

[0045] In the above-mentioned epitaxial growth device 1, since the lifting pin support part 93 is closer to the lower lamp group 7 than the base support part 91, part of the radiant heat generated by the lower lamp group 7 will first pass through the lifting pin support part 93 before passing through the base support part 91 when being transmitted to the wafer. This causes part of the radiant heat to be unable to propagate to the back of the lifting pin support part 93 due to, for example, reflection or refraction, resulting in the temperature of the area of the wafer shielded by the lifting pin support part 93 being lower than the temperature of other areas, thereby causing the wafer to be heated unevenly over its entire area, resulting in inconsistent resistivity of the epitaxial wafer as a whole.

[0046] In order to solve the above problems, referring to FIGS. 4 to 10 , according to an embodiment of the present application, a support structure 100 for an epitaxial growth device is provided. The epitaxial growth device includes a base 200, and the base 200 is used to support a wafer W thereon. The support structure 100 includes a plurality of first support arms 110 and a plurality of second support arms 120. As shown in FIG. 4 , the plurality of first support arms 110 and the plurality of second support arms 120 may be located below the base 200. The first support arms 110 and the second support arms 120 may have an elongated rod-shaped structure. The plurality of first support arms 110 may extend radially from the same center from the respective proximal ends to the distal ends. The plurality of second support arms 120 may extend from the respective proximal ends to the distal ends in a similar manner. Here, the distal end refers to an end away from the center of the base 200, and the proximal end refers to an end close to the center of the base 200.

[0047] The plurality of first support arms 110 are used to support the base 200 from below the base 200. As shown in FIG4 , each first support arm 110 may include, for example, a support portion located at its distal end, which is used to provide support at, for example, the periphery of the base 200. It is understood that, according to the needs of the epitaxial growth process, the plurality of first support arms 110 may also be used to drive the base 200 to rotate so as to uniformly grow epitaxial growth on the wafer.

[0048] The plurality of second support arms 120 are used to support the wafer from below the wafer. As shown in FIG. 4 , each second support arm 120 may include, for example, a support portion located at its distal end, which is used to provide support at, for example, the periphery of the wafer W. The plurality of second support arms 120 are capable of moving in the vertical direction. Specifically, the plurality of second support arms 120 are capable of moving between their ascending position and descending position along the vertical direction. For example, when a wafer needs to be placed in the epitaxial growth device, the second support arm 120 is in its ascending position, at which time, the support portion of the second support arm 120, for example, passes through a through hole on the base 200 and protrudes above the base 200 to receive the wafer. Subsequently, the second support arm 120 and its support portion move to the descending position to place the wafer on the base 200 for epitaxial growth.

[0049] The plurality of second support arms 120 are arranged above the plurality of first support arms 110 and correspond to the plurality of first support arms 110 in the vertical direction. Specifically, the second support arms 120 correspond to the first support arms 110 one by one. Each second support arm 120 is located directly above the corresponding first support arm 110 and is aligned with each other in the vertical direction. In other words, each second support arm 120 and its corresponding first support arm 110 are substantially in the same vertical plane, so that when viewed upward in the vertical direction, the second support arm 120 can be blocked by its corresponding first support arm 110. It should be understood that the second support arm 120 can rotate synchronously with the first support arm 110 when the first support arm 110 drives the base 200 to rotate.

[0050] In this case, when the radiant heat generated by the lower heat source propagates toward the upper wafer, the second support arm 120 is blocked by the first support arm 110 on the side facing away from or away from the lower heat source, thereby avoiding the second support arm 120 from hindering the propagation of the radiant heat, so that the temperature of the area of the wafer corresponding to the second support arm 120 is consistent with the temperature of other areas, thereby improving the overall heating uniformity of the wafer and enhancing the uniformity of the resistivity of the epitaxial wafer.

[0051] The second support arm 120 can be moved to contact the corresponding first support arm 110 over the entire longitudinal length of the second support arm 120. Specifically, the second support arm 120 can form the contact when it moves to its lowered position. Here, the "longitudinal length" of the first support arm 110 and the second support arm 120 refers to their respective lengths from the proximal end to the distal end. It should be particularly understood that the contact is not only at certain points on the longitudinal length of the second support arm 120 or only on a portion of the longitudinal length.

[0052] Exemplarily, as shown in FIGS. 7 and 8 , the second support arm 120 may have a lower surface 125, and the first support arm 110 may have an upper surface 115. When the first support arm 110 and the second support arm 120 form the above-mentioned contact, the entire lower surface 125 of the second support arm 120 and the corresponding area of the upper surface 115 of the first support arm 110 achieve seamless contact and fit (the shadow at the contact interface in FIGS. 7 and 8 is used to indicate the boundary between the first support arm 110 and the second support arm 120).

[0053] Through this design, the gap between the first support arm 110 and the second support arm 120 can be eliminated, effectively avoiding the adverse effects of the gap on heat transfer, such as local overheating or heat loss, so that the radiant heat is transmitted to the wafer with less obstruction and loss, thereby further improving the overall heating uniformity of the wafer and thereby improving the resistivity uniformity of the epitaxial wafer.

[0054] It can be understood that, as shown in FIG. 4 , the longitudinal length of the second support arm 120 can be smaller than the longitudinal length of the first support arm 110 , but is not limited thereto and can be specifically set according to the size of the base and the wafer.

[0055] It is conceivable that the support structure 100 may include at least three first support arms 110 and at least three second support arms 120. It is also conceivable that the plurality of first support arms 110 and the plurality of second support arms 120 may be evenly distributed in the circumferential direction.

[0056] In some embodiments, each first support arm 110 may include a first arcuate surface 111, each second support arm 120 may include a second arcuate surface 121, and when the first support arm 110 comes into contact with the corresponding second support arm 120, the first arcuate surface 111 cooperates with the second arcuate surface 121 to form a cylindrical surface.

[0057] Specifically, the second arc surface 121 extends over the entire longitudinal length of the second support arm 120, and any cross section of the second support arm 120 in its longitudinal length is in the shape of the second arc. The first arc surface 111 extends at least over the longitudinal length of the first support arm 110 corresponding to the second support arm 120, and any cross section of the first support arm 110 in the corresponding longitudinal length is in the shape of the first arc. The first arc and the second arc are complementary in geometry, so that they can cooperate to form a complete circle.

[0058] Exemplarily, as shown in Figures 7 and 8, the first support arm 110 may include a lower surface with a semicircular cross-section, and the second support arm 120 may include an upper surface with a semicircular cross-section. When the two come into contact, the two semicircular surfaces are aligned with each other and form a cylindrical surface with a circular cross-section.

[0059] By making the overall structure formed by the first support arm 110 and the second support arm 120 have a cylindrical surface, the continuous and smooth convex surface can promote the dissipation of radiant heat and avoid the convergence of radiant heat, so that the heat can be radiated to the surrounding space more evenly, thereby further improving the overall heating uniformity of the wafer, which is conducive to improving the uniformity of the resistivity of the epitaxial wafer.

[0060] It should be understood that there is no limitation on the curvature of the first curved surface 111 and the curvature of the second curved surface 121, as long as the sum of the two is equal to the curvature corresponding to a complete circle.

[0061] In some embodiments, as shown in FIG. 9 , one of the first support arm 110 and the corresponding second support arm 120 may include a recess 112 and the other may include a protrusion 122 , and the first support arm 110 and the corresponding second support arm 120 may form contact through the cooperation of the recess 112 and the protrusion 122 .

[0062] Specifically, the concave portion 112 and the convex portion 122 have complementary shapes and are aligned with each other in the vertical direction so that the two can be fitted together without gap or substantially without gap. When the concave portion 112 and the convex portion 122 are matched, the first support arm 110 and the corresponding second support arm 120 are in contact at least in the area corresponding to the concave portion 112 and the convex portion 122.

[0063] For example, as shown in FIG9 , the first support arm 110 may include a concave portion 112 at its upper portion, and the second support arm 120 may include a convex portion 122 at its lower portion. When the second support arm 120 descends, the convex portion 122 moves downward and fits into the concave portion 112. When the second support arm 120 ascends, the convex portion 122 moves upward and disengages from the concave portion 112. It should be understood that the shapes of the concave portion 112 and the convex portion 122 are not limited to the square shape in FIG9 , but can be any shape as long as the shapes of the two are complementary.

[0064] The first support arm 110 and the second support arm 120 can be horizontally locked by the cooperation of the concave portion 112 and the convex portion 122, so that the relative positions of the two in the horizontal direction remain fixed. When the first support arm 110 drives the base 200 to rotate, the first support arm 110 and the second support arm 120 can rotate together as a whole without relative sliding or separation, which effectively improves the stability of the two during rotation.

[0065] In addition, the concave portion 112 and the convex portion 122 can also play a vertical guiding role for the contact between the first support arm 110 and the second support arm 120. In particular, for the case where the first arc surface 111 and the second arc surface 121 cooperate, this vertical guiding role helps to ensure that the first arc surface 111 and the second arc surface 121 are accurately aligned and cooperate to form a smooth cylindrical surface.

[0066] In some embodiments, each second support arm 120 may include an arm portion 123 and a pin portion 124, and the pin portion 124 and the arm portion 123 may be formed as one piece and extend in a vertical direction to provide support for the wafer.

[0067] The pin portion 124 and the arm portion 123 can be formed into one piece by, for example, casting, forging, welding, bonding or other manufacturing processes. This integrated design enables the arm portion 123 and the pin portion 124 to move up and down as a whole. Compared with the split design, the need to align the arm portion 123 and the pin portion 124 separately is eliminated, thereby simplifying the operation process and improving the stability and consistency of movement. In addition, this integrated design reduces the number of parts that need to be installed or aligned separately, thereby saving assembly time and avoiding assembly errors.

[0068] In some embodiments, the support structure 100 for the epitaxial growth device may further include a driving member 150 for driving the plurality of second support arms 120 so that the plurality of second support arms 120 apply a force downward in a vertical direction to the plurality of first support arms 110 when the plurality of second support arms 120 come into contact with the plurality of first support arms 110, wherein the force is greater than the gravity of the plurality of second support arms 120.

[0069] Specifically, under the driving action of the driving member 150, when the plurality of second support arms 120 come into contact with the plurality of first support arms 110, the vertically downward force applied by the plurality of second support arms 120 to the contact surfaces of the plurality of first support arms 110 comes from the self-weight of the plurality of second support arms 120 and the additional force provided by the driving member 150 to the plurality of second support arms 120. The additional force is the vertically downward force or the vertically downward force component applied by the driving member 150 to the second support arms 120, which is transmitted to the contact surface of the first support arm 110 via the contact between the second support arms 120 and the first support arms 110.

[0070] Under the action of the force greater than its own gravity, the second support arm 120 can be in close contact with the first support arm 110 and press against the first support arm 110. In this case, not only the equivalent center of gravity of the two as a whole is effectively reduced, but also the friction between the contact surfaces is increased by increasing the contact pressure between the two, thereby increasing the overall rotational stability of the two. For example, this helps to suppress or reduce the deviation that may be caused by the high center of gravity of the overall structure during the process of the first support arm 110 driving the base 200 to rotate, thereby effectively avoiding the base 200 and the wafer from deviating from the center position, ensuring the uniformity of the growth of the epitaxial layer, and avoiding the degradation of the flatness of the epitaxial wafer.

[0071] It is understandable that the driving member 150 can be a push rod, a pull rod, a lead screw, a magnetic component, or other components suitable for applying a vertical downward driving force.

[0072] In some embodiments, the second support arm 120 may be a solid structure. For example, the second support arm 120 may be a solid structure formed of a material with a relatively large density or weight, such as metal, quartz, or graphite. Therefore, the weight of the second support arm 120 may be relatively large, so that when the plurality of second support arms 120 and the plurality of first support arms 110 come into contact, the center of gravity of the overall structure formed by the two may be relatively low, which is conducive to improving the balance of the overall structure and the rotational stability of the overall structure.

[0073] In some embodiments, the support structure 100 for epitaxial growth equipment may also include a first support column 130 and a second support column 140, a plurality of first support arms 110 extending toward the epitaxial growth with the first support column 130 as the center, a plurality of second support arms 120 extending toward the epitaxial growth with the second support column 140 as the center, the first support column 130 and the second support column 140 both extending in a vertical direction, and the second support column 140 being coaxially arranged inside the first support column 130 in a liftable manner.

[0074] Exemplarily, as shown in FIG. 4 , the first support column 130 and the second support column 140 may have an elongated cylindrical structure, and the central axes of the two may be collinear with the center of the base 200. A plurality of first support arms 110 may extend, for example, at an upper end portion of the first support column 130. Similarly, a plurality of second support arms 120 may extend, for example, at an upper end portion of the second support column 140. The first support column 130 may have a hollow portion for accommodating the second support column 140, the hollow portion being open at the top to allow the second support column 140 to move up and down.

[0075] The second support column 140 can form an integrated structure with the plurality of second support arms 120, so that the plurality of second support arms 120 can be driven to move up and down by the lifting and lowering of the second support column 140, thereby realizing the lifting and lowering of the wafer as required. The first support column 130 can form an integrated structure with the plurality of first support arms 110, so that the plurality of first support arms 110 can be driven to rotate by the rotation of the first support column 130 around its central axis, thereby realizing the rotation of the base 200 and the wafer.

[0076] It is conceivable that the second support column 140 may be equipped with a lifting drive mechanism, which may include, for example, a motor and a lead screw, etc. The first support column 130 may be equipped with a rotation drive mechanism, which may include, for example, a motor and a rotation shaft, etc.

[0077] In some embodiments, the support structure 100 for an epitaxial growth device may further include a retaining member 160, and the retaining member 160 is configured to keep the relative positions of the first support column 130 and the second support column 140 fixed in the horizontal direction.

[0078] It should be understood that the retaining member 160 is configured to keep the relative positions of the first support column 130 and the second support column 140 fixed in the horizontal direction without affecting the lifting of the second support column 140. Exemplarily, the retaining member 160 can be configured to keep the first support column 130 or the second support column 140 or a combination thereof fixed in the horizontal direction, for example, it can include a limiter, a guide rail and a slider mechanism, and other suitable components that can limit horizontal movement while allowing the second support column 140 to move vertically.

[0079] Providing the retaining member 160 to prevent the first support column 130 and the second support column 140 from relative movement in the horizontal direction helps to improve the stability of the overall structure formed by the two, making it less likely for the first support column 130 to deviate during rotation.

[0080] In some embodiments, the retaining member 160 may be a rolling bearing disposed between the first support column 130 and the second support column 140 and in horizontal contact with the first support column 130 and the second support column 140. In this case, there is less friction between the rolling element of the rolling bearing and the second support column 140, which facilitates the second support column 140 to be lifted and lowered steadily and smoothly.

[0081] According to an embodiment of the present application, as shown in FIG10 , an epitaxial growth device 10 is also provided, comprising a support structure 100 according to any of the aforementioned embodiments, and a base 200, the base 200 being used to support a wafer thereon. The epitaxial growth device 10 may also include an upper quartz bell 300, a lower quartz bell 400, an air inlet 500 and an air outlet 600, an upper lamp group 700, and a lower lamp group 800.

[0082] According to an embodiment of the present application, an epitaxial wafer is also provided, the epitaxial wafer is obtained using the epitaxial growth device according to the embodiment of the present application, the uniformity value of the epitaxial wafer is less than 4.08%, and the uniformity value is the ratio of the difference between the maximum value and the minimum value of the resistivity measured at multiple points on the diameter of the epitaxial wafer and the sum of the maximum value and the minimum value. That is, uniformity value = (maximum value - minimum value) / (maximum value + minimum value). The smaller the uniformity value, the better the uniformity of the resistivity.

[0083] As shown below, Table 1 shows the resistivity measured at 35 test points on the diameter of the epitaxial wafer (referred to as the first epitaxial wafer) obtained using the epitaxial growth device of FIG. 1 (comparative example) and the epitaxial wafer (referred to as the second epitaxial wafer) obtained using the epitaxial growth device according to the embodiment of the present application (example). Table 2 shows the statistical results of the data in Table 1. Test points Resistivity (ohm·cm) NO. X(mm) Y(mm) Comparative Example Example 1 -148 0 9.72 9.81 2 -147 0 9.87 9.79 3 -145 0 9.75 9.71 4 -140 0 9.72 9.77 5 -130 0 9.84 9.78 6 -120 0 9.86 9.85 7 -110 0 9.77 9.74 8 -100 0 9.92 9.85 9 -90 0 9.91 9.93 10 -80 0 10.09 10.08 11 -70 0 10.24 10.09 12 -60 0 10.37 10.13 13 -50 0 10.47 10.22 14 -40 0 10.37 10.07 15 -30 0 10.28 9.88 16 -20 0 10.21 9.77 17 -10 0 10.17 9.82 18 0 0 10.25 9.81 19 10 0 10.24 9.82 20 20 0 10.22 9.86 21 30 0 10.28 9.87 22 40 0 10.40 9.96 23 50 0 10.42 10.11 24 60 0 10.32 10.06 25 70 0 10.26 10.06 26 80 0 10.11 9.96 27 90 0 9.95 9.92 28 100 0 9.91 9.78 29 110 0 9.86 9.84 30 120 0 9.90 9.89 31 130 0 9.90 9.75 32 140 0 9.88 9.78 33 145 0 9.68 9.68 34 147 0 9.65 9.77 35 148 0 9.82 9.79

[0084] Table 1 Data statistics results Comparative Example Example Maximum value (ohm cm) 10.47 10.22 Minimum value (ohm cm) 9.65 9.68 Average value (ohm cm) 10.05 9.89 Homogeneity value (%) 4.08 2.71

[0085] Table 2

[0086] As can be seen from Table 2, the maximum value of the resistivity of the first epitaxial wafer at the 35 test points on the diameter is 10.47 ohm·cm, the minimum value is 9.65 ohm·cm, and the uniformity value obtained is 4.08%. The uniformity value of the second epitaxial wafer is less than the uniformity value of the first epitaxial wafer, that is, less than 4.08%. More specifically, the uniformity value obtained by the second epitaxial wafer can be less than 3%. Specifically, the maximum value of the resistivity of the second epitaxial wafer at the 35 test points on the diameter is 10.22 ohm·cm, the minimum value is 9.68 ohm·cm, and the uniformity value obtained is 2.71%.

[0087] Figure 11 shows the resistivity change curve C1 of the first epitaxial wafer obtained in the comparative example, and the resistivity change curve C2 of the second epitaxial wafer obtained in the embodiment. The curves C1 and C2 in Figure 11 are drawn based on the data results in Table 1, where the abscissa is the position corresponding to the measurement point, and the ordinate is the resistivity value corresponding to the measurement point.

[0088] As shown in Figure 11, compared with the resistivity change curve of the central area of the first epitaxial wafer (especially in the area with a diameter of -70mm~70mm), the resistivity change curve of the corresponding central area of the second epitaxial wafer is smoother, and the overall resistivity value is relatively lower.

[0089] The above results all indicate that by adopting the epitaxial growth device according to the embodiment of the present application, the resistivity uniformity of the epitaxial wafer can be effectively improved, thereby improving the quality of the epitaxial wafer.

[0090] Although the present application has been described with reference to exemplary embodiments, it should be understood that the present application is not limited to the specific embodiments described and shown in detail herein. Those skilled in the art may make various changes to the exemplary embodiments without departing from the scope defined by the claims of the present application.

[0091] The features mentioned and / or shown in the above description of the exemplary embodiments of the present application may be combined in the same or similar manner into one or more other embodiments, combined with the features in other embodiments or substituted for the corresponding features in other embodiments. The technical solutions obtained by these combinations or substitutions shall also be deemed to be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

[0092] 1: Epitaxial growth equipment 2: Upper quartz bell 3: Lower quartz bell 4: Air Inlet 5: Air outlet 6: Upper light group 7: Lower light group 8: Base 9: Support structure 91: base support part 92: Lifting pin 93: Lifting pin support W: Wafer C1: Resistivity change curve C2: Resistivity change curve 10: Epitaxial growth equipment 100:Support structure 110: first support arm 111: first curved surface 112: concave part 115: Upper surface 120: Second support arm 121: Second curved surface 122:convex part 123: Arm 124: Sales Department 125: Lower surface 130: First support column 140: Second support column 150: driving component 160: Holding member 200: Base 300: Upper quartz bell 400: Lower quartz bell 500: Air Inlet 600: Air outlet 700: Upper light group 800: Lower light group

Claims

1. A support structure for an epitaxial growth apparatus, comprising: A plurality of first support arms for supporting the base from below the base of the epitaxial growth apparatus for supporting the wafer thereon; The wafer includes a plurality of second support arms that are movable in the vertical direction and are used to support the wafer from below. The plurality of second support arms are disposed above the plurality of first support arms and correspond to the plurality of first support arms in the vertical direction. The second support arms are movable to contact the corresponding first support arm along the entire longitudinal length of the second support arm.

2. The support structure for the epitaxial growth apparatus as described in claim 1, wherein, Each of the first support arms includes a first arcuate surface, each of the second support arms includes a second arcuate surface, and when the first support arm and the corresponding second support arm form the contact, the first arcuate surface and the second arcuate surface cooperate to form a cylindrical surface.

3. The support structure for the epitaxial growth apparatus as described in claim 1 or 2, wherein, One of the first support arm and the corresponding second support arm includes a protrusion and the other includes a recess, and the first support arm and the corresponding second support arm can form the contact through the cooperation of the protrusion and the recess.

4. The support structure for the epitaxial growth apparatus as described in claim 1, wherein, Each of the second support arms includes an arm portion and a pin portion, the pin portion being integrally formed with the arm portion and extending in a vertical direction to provide support for the wafer.

5. The support structure for the epitaxial growth apparatus as described in claim 1, wherein, It also includes a driving member for driving the plurality of second support arms such that when the plurality of second support arms form contact with the plurality of first support arms, the plurality of second support arms apply a downward force in a vertical direction to the plurality of first support arms, wherein the force is greater than the weight of the plurality of second support arms.

6. The support structure for the epitaxial growth apparatus as described in claim 1, wherein, The second support arm is a solid structure.

7. The support structure for the epitaxial growth apparatus as described in claim 1, wherein, It also includes a first support column and a second support column. The plurality of first support arms extend radially outward from the center of the first support column, and the plurality of second support arms extend radially outward from the center of the second support column. Both the first support column and the second support column extend vertically, and the second support column is coaxially arranged inside the first support column in a liftable manner.

8. The support structure for the epitaxial growth apparatus as described in claim 7, wherein, It also includes a retaining member configured to keep the relative positions of the first support column and the second support column fixed in the horizontal direction.

9. The support structure for an epitaxial growth apparatus as described in claim 8, wherein, The retaining member is a rolling bearing disposed between the first support column and the second support column and in contact with the first support column and the second support column in the horizontal direction.

10. An epitaxial growth apparatus, comprising: A base on which the wafer is supported; And a support structure for an epitaxial growth apparatus as described in any of claims 1 to 9.

11. An epitaxial wafer obtained using the epitaxial growth apparatus as described in claim 10, the epitaxial wafer having a uniformity value of less than 4.08%, the uniformity value being the ratio of the difference between the maximum and minimum resistivity values ​​measured at a plurality of points along the diameter of the epitaxial wafer and the sum of the maximum and minimum values.

12. The epitaxial wafer as described in claim 11, wherein, The uniformity value is less than 3%.

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