Substrate carrying mechanism, tray assembly and silicon carbide epitaxial apparatus

Abstract

A substrate carrying mechanism, a tray assembly and a silicon carbide epitaxial apparatus. The substrate carrying mechanism comprises a substrate outer ring, a substrate inner ring and a substrate fixing portion, wherein a hollowed-out area is provided in the middle of the substrate inner ring, a positioning portion is provided on the inner side of the substrate inner ring, and transition portions are provided on two sides of the positioning portion, respectively; the substrate outer ring is sleeved on the substrate inner ring, and the substrate outer ring is joined to the substrate inner ring in an overlapping manner; and the substrate fixing portion is located below the substrate inner ring, a support portion is provided on the substrate fixing portion, the projection of the support portion on the substrate inner ring falls within the hollowed-out area, the support portion comprises discrete protrusions or sub-protrusions, and the protrusions or the sub-protrusions are configured to support a substrate. By means of such a design, the phenomena of substrate warping and delamination during epitaxial growth can be reduced, and the uniformity of the temperature on a substrate side can also be improved to ensure the quality of epitaxy.

Description

A substrate carrying mechanism, tray assembly and silicon carbide epitaxial equipment Technical Field

[0001] The present application relates to the technical field of chemical vapor deposition equipment, and in particular to a substrate carrying mechanism, a tray assembly, and a silicon carbide epitaxial device. Background Art

[0002] When the silicon carbide epitaxial growth equipment is in operation, the substrate is placed on a graphite tray in the reaction chamber for heating. The reaction gas flows through the surface of the substrate, which has been heated to the reaction temperature, and a chemical reaction occurs on the surface to produce a single crystal film of a certain thickness. To ensure the uniformity of the temperature and gas flow field on the substrate side, the graphite tray needs to rotate at high speed (usually at a speed of 500 rpm or more). Under the high-temperature and high-speed rotation state, it is very easy to cause problems such as substrate flying discs, flying flakes, and particles falling on the substrate. In addition, the concentration uniformity of the epitaxial process is very sensitive to temperature, and improving the uniformity of the temperature zone on the substrate side is also a key link in the process.

[0003] A cross-sectional diagram of the substrate support mechanism currently used in silicon carbide epitaxial growth is shown in FIG1 . The substrate inner ring 1 rests on the substrate outer ring 2 . Under this structure, when heated, the overlapping surface 1b of the substrate inner ring will warp and deform due to the high temperature. This deformation will lift the substrate inner ring, thereby correspondingly raising the bottom surface of the substrate inner ring 1 . During high-speed rotation, the substrate 10 located inside the substrate inner ring 1 is subjected to centrifugal force and may move and insert under / below the bottom surface 1c of the substrate inner ring 1 , thereby causing waste or even flying wafers (the substrate may fly out of the tray). A top view of the substrate support mechanism is shown in FIG2 . During high-speed rotation, under the action of centrifugal force, the tip 11 of the substrate positioning edge 12 of the substrate 10 will contact the corresponding cut edge 1a of the substrate positioning edge of the substrate inner ring 1 . At the same time, the tip 11 of the substrate positioning edge 12, along a 180° angle around the outer circumference of the substrate, will make tangential contact with the substrate inner ring 1 .

[0004] During the heating process, the substrate 10 expands due to the heat. Taking a 6-inch silicon carbide substrate and a graphite tray as an example, according to the thermal expansion formula: ΔL = α × ΔT × L, where ΔL is the expansion in mm, α is the average thermal expansion coefficient in mm / mm·K, ΔT is the temperature difference in K, and L is the original length in mm. The expansion of a 6-inch silicon carbide substrate from room temperature 293K to 1273K is ΔL = 4.4 × 10 -6×(1273-293)×150=0.65mm. Under this deformation, the two ends of the substrate 10 (the two ends with length L in FIG2 ) are stuck against the inner ring 1 of the substrate. At this time, stress is concentrated at the tip 11 of the substrate positioning edge. When external conditions change (such as temperature, flow field, pressure, rotation speed, etc.), stress release at this tip is very likely to occur. This will cause two hazards to process growth: 1) During the reaction process, in addition to deposition on the substrate, a large amount of deposition will also be generated on the inner ring 1 of the substrate. The stress release at the tip 11 will cause the deposits deposited on the inner ring 1 at this location to collapse, posing a risk of particles falling onto the surface of the substrate 10. During the reaction growth process, the particles that fall are buried, forming defects, resulting in a reduction in the growth yield. 2) As the temperature in the reaction chamber further increases, the expansion increases, and the increased stress causes elastic deformation of the substrate 10. When the balance is destroyed, the elastic potential energy is released, causing flying chips. The substrate 10 flies out and breaks into pieces under high-speed rotation, damaging other important components in the reaction chamber.

[0005] Summary of the Invention

[0006] In order to overcome the above shortcomings, the purpose of this application is to provide a substrate carrying mechanism, a tray assembly and a silicon carbide epitaxial device, wherein the tray assembly can reduce flying discs and flying wafers, improve the substrate temperature uniformity to ensure the quality of the grown epitaxial film.

[0007] In order to achieve the above objectives, this application adopts the following technical solutions:

[0008] A substrate supporting mechanism, used in an epitaxial device to support a substrate, comprising:

[0009] Substrate outer ring, substrate inner ring and substrate fixing part,

[0010] The middle part of the substrate inner ring has a hollow area, the inner side of the substrate inner ring has a positioning portion, and both sides of the positioning portion have transition portions respectively;

[0011] The substrate outer ring is sleeved on the substrate inner ring, and the substrate outer ring is overlapped on the substrate inner ring;

[0012] The substrate mounting portion is located below the inner substrate ring. A support portion is provided on the substrate mounting portion, and its projection onto the inner substrate ring falls within the hollowed-out area. The support portion includes discrete protrusions or sub-protrusions, which are used to support the substrate. The epitaxial growth apparatus may be a silicon carbide epitaxial growth apparatus. This design utilizes the outer substrate ring nestled within the inner substrate ring, preventing the outer substrate ring from thermally expanding during epitaxial growth and reducing / avoiding substrate discs and flakes. This architecture also utilizes the outer substrate ring's own weight to press against the inner substrate ring, reducing warping and preventing substrate discs and flakes during epitaxial growth. By optimizing the support portion's structure, the contact area with the substrate during epitaxial growth is reduced, minimizing temperature fluctuations at the contact point, ensuring uniform substrate temperature (within a 2° temperature difference between the center and edge of the substrate), and ensuring more uniform heat radiation, thereby ensuring high-quality epitaxial growth. The protrusions or sub-protrusions may be discrete.

[0013] A substrate supporting mechanism, used in an epitaxial device to support a substrate, comprising:

[0014] Substrate outer ring, substrate inner ring and substrate fixing part,

[0015] The middle part of the substrate inner ring has a hollow area, the inner side of the substrate inner ring has a positioning portion, and both sides of the positioning portion have transition portions respectively;

[0016] The substrate outer ring is sleeved on the substrate inner ring, and the substrate outer ring is overlapped on the substrate inner ring;

[0017] The substrate fixing portion is located below the substrate inner ring, and a support portion is provided on the substrate fixing portion, and the support portion is projected onto the substrate inner ring side and falls on the hollow area, and the support portion includes discrete protrusions or sub-protrusions, and the protrusions or sub-protrusions are used to support the substrate. Preferably, the substrate outer ring is sleeved on the substrate inner ring, and the substrate outer ring overlaps the substrate inner ring (the substrate inner ring can be pressed by its own weight), and further, the inner side of the substrate outer ring has a first protrusion extending along its radial direction, and the axial thickness of the first protrusion is less than the axial thickness of the substrate outer ring, and the outer side of the substrate inner ring has a second protrusion extending along its radial direction, and the axial thickness of the second protrusion is less than the axial thickness of the substrate outer ring, the first protrusion abuts the second protrusion, and the first protrusion is located above the second protrusion (the first protrusion is used to press the second protrusion to press the substrate inner ring to reduce the occurrence of flying discs / flakes). Through such a design, the deadweight of the outer ring of the substrate can be used to press on the inner ring of the substrate, which can reduce / avoid the phenomenon of flying discs and flying flakes of the substrate during epitaxial growth; by optimizing the structure of the support part, the contact area with the substrate during epitaxial growth is reduced, and the temperature mutation in the contact point area is reduced, the temperature uniformity on the substrate side can be improved (the temperature difference between the temperature at the center of the substrate and the temperature at the edge of the substrate is within 2°), making the radiated heat more uniform to ensure the quality of the grown epitaxial. The protrusion or sub-protrusion can be a discrete design. The epitaxial equipment can be a silicon carbide epitaxial equipment. The outer ring of the substrate and the inner ring of the substrate can be made of a material or a protective film (such as a silicon carbide film) can be coated on the graphite material. The combined thickness of the first protrusion and the second protrusion is the same or approximately the same as the axial thickness of the outer ring of the substrate or the axial thickness of the inner ring of the substrate.

[0018] In one embodiment, a support ring is further included, which is disposed inside the inner ring, and the substrate holding portion is disposed on the support ring. The substrate holding portion is provided to minimize the contact area with the substrate, thereby reducing the amount of heat transferred to the substrate through the substrate holding portion during the epitaxial reaction, which could lead to localized temperature spikes.

[0019] In one embodiment, the transition portion has rounded corners and / or beveled edges. Thus, when the substrate expands under high temperature, the substrate positioning edge expands / extends along the tangent direction of the rounded corners or the beveled edge of the transition portion, thereby preventing the sharp corners of the substrate from being constrained and thus preventing the substrate from being stuck by the inner ring of the substrate.

[0020] In one embodiment, the substrate holding portion is in the form of a cylindrical, truncated cone, a boss formed by discontinuous circular rings, a rectangular platform, or a trapezoidal platform. By optimizing the structure of the substrate holding portion to reduce the contact area with the substrate, heat is reduced from being directly transferred to the substrate through the substrate holding portion during the epitaxial reaction, thereby avoiding the formation of localized temperature spikes.

[0021] In one embodiment, the inner side of the substrate outer ring has a first protrusion extending along its radial direction, and the axial thickness of the first protrusion is smaller than the axial thickness of the substrate outer ring.

[0022] The outer side of the substrate inner ring has a second protrusion extending in its radial direction, and the axial thickness of the second protrusion is smaller than the axial thickness of the substrate outer ring, the first protrusion abuts against the second protrusion, and the first protrusion is located above the second protrusion.

[0023] An accommodating cavity is defined between the second protruding portion and the outer ring of the substrate, and the accommodating cavity is used for accommodating a first clamping portion on one side of the substrate and protruding along the axial direction thereof.

[0024] The present application provides a tray assembly, which includes:

[0025] A rotating component is provided with a cover plate on one side of the rotating component, and the cover plate is equipped with the substrate carrying mechanism.

[0026] The present application provides a tray assembly, which includes:

[0027] A rotating component is provided with a cover plate on one side of the rotating component. The cover plate has a body. A fifth protruding rib, a step portion, and a recess are sequentially provided on the side of the fourth protruding rib on the body away from the third protruding rib. The recess is located in the middle of the body. When a substrate is placed on the upper side of the body, the distances from the fifth protruding rib, the step portion, and the recess to the substrate gradually decrease.

[0028] The cover plate is equipped with the substrate supporting mechanism.

[0029] The present application provides a tray assembly, which includes:

[0030] A rotating component is provided with a cover plate on one side of the rotating component. The cover plate has a body. The end of the body has a third protruding rib extending radially thereof. The side of the body close to the third protruding rib is provided with a fourth protruding rib. The side of the body away from the third protruding rib is provided with a fifth protruding rib, a step portion and a recess in sequence. The recess is located in the middle of the body. When a substrate is placed on the upper side of the body, the gap between the surface of the body and the substrate changes.

[0031] The cover plate is equipped with the substrate supporting mechanism.

[0032] In one embodiment, one side of the rotating component has a flat portion extending radially inward, an end of the flat portion has a second protruding rib extending radially, and the second protruding rib has a notch extending axially, and the axial thickness of the second protruding rib is smaller than the axial thickness of the flat portion.

[0033] The cover plate has a body, and an end portion of the body has a third protruding rib extending in its radial direction and at least one protruding portion. The protruding portion is embedded in the notch and abuts against the second protruding rib.

[0034] In one embodiment, the flat portion has a first protruding rib extending along the axial direction of the rotating component, and the first protruding rib is annular or a combination thereof is annular.

[0035] In one embodiment, a fourth protruding rib is provided on the side of the main body close to the third protruding rib, and a stepped portion is provided on the side of the fourth protruding rib away from the third protruding rib. When there is a substrate on the upper side of the main body, the stepped portion is constructed to change the setting between the surface of the main body and the substrate to improve the heat radiated and conducted to the substrate through the main body.

[0036] An embodiment of the present application provides a silicon carbide epitaxial growth device, which includes: a reaction chamber having a spray component on the top, and the bottom side of the reaction chamber having the above-mentioned tray assembly.

[0037] The substrate supporting mechanism and tray assembly proposed in the present application have the following beneficial effects: through structural optimization, when the substrate outer ring and the substrate inner ring are combined, the substrate outer ring overlaps the substrate inner ring, and the overlapping surface can be a plane or an inclined surface. In this way, the substrate outer ring deforms due to temperature rise during epitaxial growth, and this deformation will not affect the substrate inner ring, thus avoiding the substrate from being inserted under the substrate inner ring, causing the problem of flying discs or flying chips. By setting a substrate fixing part and optimizing its structure to reduce its contact area with the substrate, the heat conducted to the substrate through the substrate fixing part during the epitaxial reaction is minimized, so that the temperature on the substrate side is uniform, thereby ensuring the quality of epitaxy. By optimizing the structure of the cover body, a stepped portion is provided on the side of the fourth protruding rib away from the third protruding rib. When the substrate is placed on the cover, there is a gap between the bottom of the substrate and the surface of the cover body. The gap is set to change, thereby improving the heat conducted to the substrate through the body radiation, ensuring the uniformity of the temperature field on the substrate side. By optimizing the structure of the positioning portion of the substrate inner ring, transition portions are provided on both sides. When the substrate is heated and expanded under high temperature, it expands along the rounded tangent or hypotenuse direction of the transition portion, avoiding the sharp corners of the substrate from being constrained and getting stuck by the substrate inner ring, thereby reducing the probability of particles falling onto the substrate surface and improving the epitaxial growth yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings are intended to facilitate understanding of the technical solutions of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solutions of the present disclosure and do not constitute a limitation of the technical solutions of the present disclosure. The shapes and sizes of the components in the accompanying drawings do not reflect the actual scale and are intended only to illustrate the contents of this application.

[0039] FIG1 is a schematic cross-sectional view of a conventional substrate supporting mechanism.

[0040] FIG. 2 is a schematic diagram of an existing substrate carrying mechanism after placing a substrate.

[0041] FIG3 is a schematic diagram of the three-dimensional structure of the tray assembly according to an embodiment of the present application.

[0042] FIG. 4 is a schematic diagram of the tray assembly of FIG. 3 at a different viewing angle.

[0043] FIG5 is a schematic diagram of an isometric cross-section taken at AA in FIG4 .

[0044] FIG6 is a schematic cross-sectional view taken along line AA in FIG4 .

[0045] FIG7 is a partial enlarged schematic diagram of point a in FIG6 .

[0046] FIG8 is a schematic cross-sectional view of a substrate supporting mechanism according to another embodiment of the present application.

[0047] FIG9 is a partial enlarged schematic diagram of point c in FIG8 .

[0048] FIG10 is a schematic cross-sectional view taken along line BB in FIG4 .

[0049] FIG11 is a partial enlarged schematic diagram of point b in FIG10 .

[0050] FIG12 is a schematic structural diagram of FIG4 with the substrate hidden.

[0051] FIG13 is a schematic structural diagram of the outer ring of the substrate in FIG12 .

[0052] FIG14 is a schematic structural diagram of the inner ring of the substrate in FIG13 .

[0053] FIG15 is a perspective schematic diagram of a rotating component according to an embodiment of the present application.

[0054] FIG16 is a schematic diagram of the structure of FIG15 with the cover plate hidden.

[0055] FIG17 is a schematic structural diagram of the cover plate in FIG15 .

[0056] FIG18 is a schematic structural diagram of the bottom plate in FIG15 .

[0057] FIG19 is a schematic diagram of the three-dimensional structure of the substrate fixing portion according to an embodiment of the present application.

[0058] FIG20 and FIG21 are schematic diagrams showing a substrate in a stable state after being placed on a substrate supporting mechanism according to an embodiment of the present application. DETAILED DESCRIPTION

[0059] The above scheme is further described below with reference to specific examples. It should be understood that these examples are intended to illustrate the present application and are not intended to limit the scope of the present application. The implementation conditions used in the examples can be further adjusted according to the conditions of the specific manufacturer. The implementation conditions not specified are generally those used in routine experiments.

[0060] The present application discloses a substrate support mechanism, a tray assembly, and silicon carbide epitaxial growth equipment. The substrate support mechanism includes a substrate outer ring, a substrate inner ring, and a substrate fixing portion. The inner ring has a hollowed-out region in the middle. The outer ring is sleeved onto the inner ring and overlaps the inner ring. The substrate fixing portion is located below the inner ring and is provided with a support portion. The support portion, projected onto the inner ring, falls within the hollowed-out region. The support portion includes discrete protrusions or sub-protrusions for supporting the substrate. This design reduces the occurrence of flying discs and flakes during epitaxial growth and improves substrate-side temperature uniformity to ensure epitaxial growth quality. The substrate can be 4 inches, 6 inches, 8 inches, or 12 inches in size. The substrate (also called a wafer) can be a silicon substrate, a silicon carbide substrate, a gallium nitride substrate, a diamond substrate, a boron nitride substrate, or a gallium oxide substrate.

[0061] Next, the substrate supporting mechanism, tray assembly and silicon carbide epitaxial equipment proposed in this application are described with reference to Figures 3 to 21.

[0062] FIG3 is a schematic diagram of the three-dimensional structure of a tray assembly according to an embodiment of the present application. The tray assembly includes a substrate carrying mechanism 100 and a rotating component 150.

[0063] The substrate supporting mechanism 100 is used to place a substrate 200 (the schematic top view after the substrate 200 is placed is shown in FIG4 ).

[0064] The substrate carrier 100 is placed on a rotating member 150 and is driven by the rotating member 150 to rotate the substrate carrier 100, thereby rotating the substrate. Preferably, the rotating member 150 is connected to a driving member (such as a driving motor, not shown), and is driven by the driving member to rotate the rotating member.

[0065] An isometric cross-sectional view of the tray assembly at AA in FIG4 is shown in FIG5 , and a cross-sectional view is shown in FIG6 .

[0066] The substrate carrying mechanism 100 includes: a substrate outer ring 110, a substrate inner ring 120, a support ring 140 and a base plate 130.

[0067] The middle portion of the substrate inner ring 120 is a hollow area for accommodating the substrate;

[0068] The substrate outer ring 110 is sleeved on the substrate inner ring 120, and the substrate outer ring 110 is overlapped on the substrate inner ring 120.

[0069] The base plate 130 is hollow and annular, with a first clamping portion 131 protruding along its axial direction on one side. The base plate has a first receiving portion 132, which is arranged on the same side as the first clamping portion 131. The base plate also has a second receiving portion 133, which is arranged opposite to the first receiving portion 132.

[0070] The first receiving portion 132 is used to accommodate a support ring 140. One side of the support ring 140 has a protrusion 141 extending along its axial direction. The protrusion 141 is used to abut (support) the placed substrate 200. The projection of the protrusion 141 on the inner ring side of the substrate falls on the hollow area. The protrusion 141 is used to support the placed substrate. Preferably, the protrusion 141 can be cylindrical, see Figure 9, which is a partial enlarged schematic diagram at point b in Figure 8, or see Figure 19, which is a schematic diagram of the three-dimensional structure of the substrate fixing part. Preferably, the substrate fixing part includes a support ring 140. In other embodiments, the substrate fixing part includes a support ring and a substrate, and the support ring and the substrate can be designed as an integral whole. Preferably, the combination of protrusions 141 is circular, and the diameter is smaller than the diameter (outer diameter) of the substrate. The protrusion 141 can be a truncated cone, a protrusion formed by discontinuous circular rings, a rectangular platform, a trapezoidal platform, or other geometrical protrusions. This design minimizes the contact area between the protrusion and the substrate, reduces the amount of heat generated by the heater in the rotating component 150 during the epitaxial reaction that is transferred to the substrate through the protrusion, reduces temperature fluctuations in the contact area, and improves substrate-side temperature uniformity (the temperature difference between the center of the substrate and the edge of the substrate is within 2°). This can improve the thickness and concentration uniformity within the grown epitaxial wafer. The axial depth / thickness of the first receiving portion 132 is the same or approximately the same as the axial thickness of the support ring 140 (excluding the height of the protrusion). Thus, after the support ring 140 is placed in the first receiving portion 132, its top surface is flush or approximately flush with the top surface 130a of the substrate 130. The outer ring of the substrate is overlapped on the inner ring of the substrate, that is, the outer ring of the substrate is partially pressed on the inner ring of the substrate. In this way, the outer ring of the substrate will deform due to temperature increase during epitaxial growth, and the deformation will not affect the inner ring of the substrate, thereby avoiding the problem of flying discs or flying chips caused by the substrate being inserted under the inner ring of the substrate.

[0071] A cross-sectional view of the tray assembly from one perspective is shown in Figure 6 , with a partial enlargement of point a in Figure 6 shown in Figure 7 . Variations of the embodiment of Figure 7 are shown in Figures 8 and 9 . Figure 8 is a schematic cross-sectional view of a substrate support mechanism according to one embodiment, and Figure 9 is a schematic enlargement of point c in Figure 8 . One side of the support ring 240 has a protrusion 241 extending axially therefrom. This protrusion 241 may be continuous (overall, the protrusion 241 is annular). Sub-protrusions 2411 are provided on the protrusion 241, with recesses between adjacent sub-protrusions 2411. The provision of the sub-protrusions 2411 reduces the contact area with the substrate, thereby reducing the formation of temperature spikes at the contact points (which can hinder process temperature field adjustment), thereby ensuring that the temperature difference between the center and edge of the substrate is within 2°C. In other embodiments, the protrusion 241 may be discrete, and the discrete protrusion 241 may be combined with the sub-protrusion 2411 to further reduce the contact area with the substrate. In this way, while ensuring support, the temperature difference between the center side and the edge side of the substrate is ensured to be within 2°C during the epitaxial process.

[0072] The inner side of the substrate outer ring 110 has a first protrusion 111 extending along its radial direction, and the thickness H2 of the first protrusion 111 is less than the thickness H1 of the substrate outer ring 110. Preferably, the thickness H2 of the first protrusion 111 is half of the thickness H1 of the substrate outer ring 110.

[0073] The outer side of the substrate inner ring 120 has a second protrusion 121 extending radially outward, and a thickness H3 of the second protrusion 121 is smaller than a thickness H4 of the substrate outer ring 120 . The inner side of the substrate inner ring 120 has a positioning portion 122 (sometimes also called a cutting edge), and the two sides of the positioning portion 122 respectively have transition portions 122a, and the transition portion 122a has a rounded corner 122a1 or a beveled edge 122a2). With such a design, after the substrate is placed on the substrate supporting mechanism, when the substrate 200 and the substrate inner ring 120 reach a stable state under the action of the rotating centrifugal force, the substrate positioning edge 210 is tangent to the rounded corner 122a1 of the transition portion 122a of the substrate inner ring 120 (see Figure 20) or is collinear with the beveled edge 122a2 of the transition portion 122a of the substrate inner ring 120 (see Figure 21). Even if the substrate is heated under high temperature, the substrate positioning edge will expand along the tangent direction or beveled direction of the rounded corner of the transition portion 122a, and the sharp corner 211 of the substrate 200 will not be constrained and will not be stuck with the substrate inner ring.

[0074] When the substrate outer ring 110 is combined with the substrate inner ring 120, the first protrusion 111 abuts against the second protrusion 121, and the first protrusion 111 is located above the second protrusion 121 (so that the substrate inner ring can be pressed by its own weight). A accommodating cavity is defined between the second protrusion 121 and the substrate outer ring 110 (the radial extension length of the first protrusion 111 is longer than the radial extension length of the second protrusion 121, so that after overlapping, the first protrusion 111, the second protrusion 121, and the substrate outer ring 110 together form an accommodating cavity for accommodating the first clamping portion 131). The accommodating cavity is used to accommodate the first clamping portion 131. In this embodiment, the thickness of the combination of the first protrusion 111 and the second protrusion 121 is the same as or substantially the same as the thickness of the substrate outer ring 110 or the thickness of the substrate inner ring 120. By positioning the first protrusion 111 above the second protrusion 121, the outer substrate ring 110 deforms due to temperature rise during epitaxial growth. This deformation has no effect on the position of the inner substrate ring relative to the substrate, thus preventing the substrate from being inserted below the inner substrate ring and causing flying discs and fragments. Furthermore, by positioning the first protrusion 111 above the second protrusion 121, the weight of the outer substrate ring 110 can be used to press against the inner substrate ring, preventing the occurrence of flying discs and fragments.

[0075] The rotating component 150 is provided with a first connecting portion 153 on one side. The first connecting portion 153 is configured to mate with the second connecting portion 172 on the base plate 170, thereby securely connecting the rotating component 150 to the base plate 170 and preventing relative sliding between the rotating component and the base plate. The first connecting portion 153 may be a notch, and the second connecting portion 172 may be a blocking portion that matches the shape of the notch. In other embodiments, the first connecting portion 153 may be a blocking portion, and the second connecting portion 172 may be a notch that matches the shape of the notch. As long as the first connecting portion 153 and the second connecting portion 172 are connected to prevent relative sliding between the rotating component and the base plate, it will be sufficient.

[0076] The other side of the rotating component 150 (away from the first connecting portion 153) has a flat portion 151 extending radially and inwardly. This flat portion 151 has a first protruding rib 152 extending axially along the rotating component 150. The first protruding rib 152 is annular (when the protruding rib 152 is continuous) or a combination thereof (when the protruding rib 152 is discontinuous). The end of the flat portion 151 has a second protruding rib 151a extending radially. This second protruding rib 151a has a second notch 151a1 defined therein. The thickness of the second protruding rib 151a is less than the thickness of the flat portion 151 (as viewed axially from the rotating component 150). In this embodiment, there are two second notches 151a1. In other embodiments, the number of second notches 151a1 may be one, three, four, or more. A heater (not shown) is disposed within the rotating component 150. This heater may be made of graphite.

[0077] The bottom plate 170 has a main body 171 in a cylindrical shape. One side of the main body 171 has a third protrusion 173 and a second connection portion 172 . A through hole 174 is formed in the middle of the bottom plate 170 for connecting the hollow rotating shaft 180 .

[0078] The cover plate 160 is provided on the side of the rotating member 150 away from the bottom plate 170.

[0079] The cover plate 160 has a main body 160a, the end of the main body 160a has a third protruding rib 161 extending radially thereof, and the thickness of the third protruding rib 161 is less than the thickness of the main body 160a (along the axial direction of the cover plate 160), and a protrusion 160b extending radially thereof is provided on the end of the main body 160a.

[0080] In one embodiment, a fourth protruding rib 162 is provided on the side of the body 160a proximal to the third protruding rib 161. This fourth protruding rib 162 is configured to abut against the support ring 140, with a gap e formed between the bottom of the support ring 140 and the body 160a. In this embodiment, the width of the fourth protruding rib 162 (in the radial direction of the body 160a) is smaller than the axial thickness of the support ring 140. This design reduces the contact area between the fourth protruding rib 162 and the support ring 140, thereby reducing the heat transfer from the fourth protruding rib 162 to the support ring 140 during the epitaxial reaction, which could lead to localized temperature spikes. In other embodiments, the fourth protruding rib 162 is provided with sub-protrusions, with recesses between adjacent sub-protrusions (see Figure 9 for the structure). This reduces the contact area between the fourth protruding rib 162 and the support ring 140, further reducing the formation of temperature spikes at these contact points. In other embodiments, the fourth protruding rib 162 may be omitted. After the support ring 140 is placed in the first receiving portion 132 , a gap is provided between the bottom of the support ring 140 and the body 160 a to prevent heat from the body 160 a from being directly transferred to the support ring 140 .

[0081] A stepped portion is provided on the side of the fourth protruding rib 162 on the body 160a that is away from the third protruding rib 161. When a substrate is positioned above the body 160a, a gap d exists between the substrate (its bottom) and the surface of the body 160a. The distance between the substrate (its bottom) and the surface of the body 160a varies (e.g., gradually increasing or decreasing from the inside out, or varying periodically or with variable periodicity). This improves the amount of heat radiated from the body 160a to the substrate, ensuring a uniform temperature field on the substrate side. When the cover plate is assembled with the rotating component 150, the protruding portion 160b fits into the second notch 151a1. After relative conversion, the protruding portion 160b abuts the second protruding rib 153, connecting the cover plate to the rotating component.

[0082] In one embodiment, a fifth rib 163, a step 164, and a recess 165 are sequentially provided on the side of the fourth rib 162 of the body 160a that is distal from the third rib 161. The recess 165 is located in the middle of the body 160a. When a substrate is placed above the body 160a, the distances (gaps) between the fifth rib 163, the step 164, and the recess 165 and the substrate (or its bottom) gradually decrease. This improves the amount of heat transferred from the body 160a to the substrate, ensuring a uniform temperature field on the substrate side. This results in uniform thickness and doping concentration in the grown epitaxial wafers. In this embodiment, the protrusion height of the fifth rib 163 is greater than that of the fourth rib 162 (as viewed in the axial direction of the body 160a).

[0083] The present application provides a silicon carbide epitaxial growth apparatus, comprising a columnar reaction chamber with a spray component at its top connected via a pipeline to a gas source for providing an epitaxial growth reaction. The bottom of the reaction chamber comprises the aforementioned tray assembly. During operation of the reaction chamber, gas sprayed from the spray component flows toward the tray assembly, reacting on the surface of a substrate on the tray assembly to grow a thin film (e.g., a single crystal thin film, also referred to as epitaxial). The tray assembly rotates at a predetermined speed during operation of the reaction chamber.

[0084] The above embodiments are intended only to illustrate the technical concepts and features of this application. Their purpose is to enable those familiar with the art to understand the content of this application and implement it accordingly. They are not intended to limit the scope of protection of this application. Any equivalent changes or modifications made in accordance with the spirit of this application shall be included in the scope of protection of this application.

Claims

1. A substrate carrier mechanism for supporting a substrate in an epitaxial device, characterized in that, Comprising: A substrate outer ring, a substrate inner ring and a substrate fixing part, A hollow area is provided in the middle of the substrate inner ring, a positioning part is provided on the inner side of the substrate inner ring, and transition parts are respectively provided on both sides of the positioning part; The substrate outer ring is sleeved on the substrate inner ring, and the substrate outer ring overlaps on the substrate inner ring. A first protruding part extending radially along the inner side of the substrate outer ring is provided, and the axial thickness of the first protruding part is smaller than the axial thickness of the substrate outer ring. A second protruding part extending radially along the outer side of the substrate inner ring is provided, and the axial thickness of the second protruding part is smaller than the axial thickness of the substrate outer ring. The first protruding part abuts against the second protruding part, and the first protruding part is located above the second protruding part. The substrate fixing part is located below the substrate inner ring. A support part is provided on the substrate fixing part, and the projection of the support part on the side of the substrate inner ring falls within the hollow area. The support part includes discrete protrusions or sub-protrusions, and the protrusions or sub-protrusions are used to support the substrate.

2. The substrate carrying mechanism according to claim 1, wherein Further comprising a support ring. The support ring is provided on the inner side of the inner ring, and the support part is provided on the support ring, and the projection of the support part on the side of the substrate inner ring falls within the hollow area, or The substrate fixing part includes a support ring and a substrate. The substrate is in a hollow ring shape. A first receiving part, a second receiving part and a first clamping part are provided on the substrate on the same side, and the first clamping part protrudes axially. The second receiving part is arranged opposite to the first receiving part. The first receiving part is used to receive the support ring. A protrusion extending axially along one side of the support ring is provided, and the protrusion is used to support the placed substrate.

3. The substrate carrying mechanism according to claim 1, wherein The transition part has a fillet and / or a bevel edge.

4. The substrate carrying mechanism according to claim 1, wherein, The substrate fixing part includes a convex platform in a geometric shape of a cylinder, a frustum of a cone, a discontinuous ring-shaped convex platform, a rectangular platform or a trapezoidal platform.

5. The substrate carrying mechanism according to claim 1, wherein A receiving cavity is provided between the second protruding part and the substrate outer ring, and the receiving cavity is used to place the first clamping part.

6. A tray assembly, characterized in that, Comprising: A rotating part, a cover plate is provided on one side of the rotating part, and the cover plate carries the substrate carrying mechanism according to any one of claims 1-5.

7. The tray assembly according to claim 6, wherein A flat part extending radially and inwards is provided on one side of the rotating part, and a second protruding rib extending radially is provided at the end of the flat part, and a notch extending axially is provided on the second protruding rib. The axial thickness of the second protruding rib is smaller than the axial thickness of the flat part. The cover plate has a body, and a third protruding rib and at least one protruding part extending radially are provided at the end of the body. After the protruding part is embedded into the notch, it abuts against the second protruding rib.

8. The tray assembly according to claim 7, wherein A first protruding rib extending axially along the rotating part is provided on the flat part, and the first protruding rib is in a circular ring shape or a combination thereof is in a circular ring shape.

9. The tray assembly according to claim 7, wherein ​ A fourth protruding rib is provided on the side of the body close to the third protruding rib, and a stepped portion is provided on the side of the fourth protruding rib away from the third protruding rib. The stepped portion is configured to set the change in the gap between the surface of the body and the substrate when there is a substrate on the upper side of the body.

10. A silicon carbide epitaxial device, characterized in that, Comprising: A reaction chamber having a spraying component at its top, The bottom side in the reaction chamber has a tray assembly as described in any one of claims 6-9.

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