Apparatus for growing semiconductor wafers and related manufacturing methods

Abstract

Embodiments of this disclosure relate to apparatus for growing semiconductor wafers and associated manufacturing methods. An apparatus for growing semiconductor wafers, particularly silicon carbide, includes a chamber housing a collection container and a support or liner disposed above the container. The support is formed of a frame surrounding an opening that receives a plurality of arms and seats. The frame has a first surface and a second surface opposite to each other, wherein the first surface of the frame faces the support. The arms are formed of cantilevered rods extending from the frame into the opening, each arm having a maximum height smaller than the frame and a resting edge at its top. The resting edge of the arm defines a resting surface at a level lower than the second surface of the frame. The seats have a bottom formed by the resting surface.

Description

Technical Field

[0001] The present invention relates to an apparatus for growing semiconductor wafers such as silicon carbide wafers, and to an associated manufacturing method. Background Art

[0002] Semiconductor devices are typically fabricated in silicon wafers. However, silicon carbide (SiC) wafers have become increasingly popular, at least in part due to the favorable chemical and physical properties of SiC. For example, SiC typically has a wider bandgap than silicon. Therefore, SiC, which is also relatively thin, has a higher breakdown voltage than silicon and can thus be advantageously used in high-voltage applications, such as in power devices.

[0003] Silicon carbide exists in various crystallographic forms or polytypes. The most common polytypes are cubic polytypes (polytype 3C-SiC), hexagonal polytypes (polytypes 4H-SiC and 6H-SiC), and rhombic polytypes (polytype 15R-SiC). Among these, cubic polytype 3C-SiC has become a subject of in-depth research due to its unique properties compared to other wafer polytypes. For example, 3C-SiC wafers typically exhibit lower trap density and higher channel electron mobility at the SiO2 / 3C-SiC interface. Other interesting properties of 3C-SiC include its on-state resistance R0. on The low value is particularly useful when the device is operating at or above 650V.

[0004] However, the manufacturing of silicon carbide wafers is more complex than that of silicon wafers, and 3C-SiC substrates are currently unavailable on the market.

[0005] US 2013 / 0157448, filed in the name of the applicant and entitled "Method for manufacturing a silicon carbide wafer and respective equipment," describes an apparatus and method for manufacturing a silicon carbide wafer (SiC). This patent application describes a method for manufacturing a SiC wafer, comprising: positioning a silicon substrate on a support (referred to as a "support") in a reaction chamber; growing a 3C-SiC epitaxial layer on the silicon substrate; and then separating the silicon substrate from the 3C-SiC epitaxial layer by melting the silicon substrate. The molten silicon is then discharged through a pair of outlets below the support.

[0006] To improve the separation of the silicon substrate from the 3C-SiC epitaxial layer, the applicant has developed an improved reaction chamber, described in US2018 / 0090350 under the title "Apparatus for manufacturing a silicon carbide wafer". Here, the support is formed of multiple rods having an inclined shape or facing downwards to facilitate the flow of molten silicon through openings between the rods. Furthermore, a sponge is arranged in a cup-shaped container below the support to collect the molten silicon and simplify the process of removing the molten silicon from the reaction chamber.

[0007] Further improvements are described in US Patent Application Serial No. 16 / 182050, filed November 6, 2018, entitled "Apparatus and method for manufacturing a wafer". Here, the support includes an outer frame defining an opening and having a plurality of arms extending from the frame toward the inside of the opening and suspended above the container. The arms are cantilevered, fixed at one end to the frame, and have a free end oriented toward the center of the opening. The free end is provided with an upwardly projecting tip.

[0008] In some cases, during the fabrication of silicon carbide wafers, a portion of the silicon adheres to, for example, the tip of a substrate and remains adhered to, for example, the tip of the substrate. Furthermore, it has been shown that in some situations, the silicon carbide wafer does not grow uniformly, but instead forms a polycrystalline outer edge. Summary of the Invention

[0009] Various embodiments of this disclosure provide an improved apparatus and method that overcomes the disadvantages of the prior art and enables the manufacture of silicon carbide wafers, even large-sized silicon carbide wafers.

[0010] According to this disclosure, an apparatus and method for growing silicon carbide wafers are provided.

[0011] In practice, this device includes a support formed by a frame, an opening in the frame, and a plurality of arms extending into the opening toward the center of the opening. The arms define a resting surface for the wafer, which is at a level lower than the frame.

[0012] In fact, research conducted by the applicant has shown that during SiC growth on a silicon substrate via induction in a CVD (chemical vapor deposition) reactor, the heat distribution within the reaction chamber is uneven, with the wafer edges being tens of degrees cooler than the center. The applicant believes this temperature gradient is due to the instability of the growth gas flow, which should overlap the initial silicon wafer in a layered manner, and the first thin SiC layer growing on the silicon substrate. Since the initial silicon wafer is at a higher level and protrudes from the substrate, it is believed that this causes instability in the growth gas flow, thus generating the temperature gradient.

[0013] To solve the above problems, the support is manufactured such that the support arm is positioned at a lower level than the frame, and the initial silicon wafer is positioned within the frame such that its top surface is approximately aligned with the top surface of the frame. Attached Figure Description

[0014] To better understand this disclosure, embodiments of the disclosure will now be described by way of non-limiting example with reference to the accompanying drawings, in which:

[0015] Figure 1 This is a cross-sectional view of one embodiment of the device;

[0016] Figure 2 Is Figure 1 A top view of one embodiment of a support member that can be used in the device;

[0017] Figure 3 From Figure 2 Perspective view above the support member;

[0018] Figure 4 yes Figure 2 Enlarged perspective view of the details of the support components;

[0019] Figure 5 It is along Figure 2 The section VV cut Figure 2 Cross-sectional view of the support component;

[0020] Figure 6 It is along Figure 2 Section VI-VI cut, through Figure 2 A cross-sectional view of a portion of the support component;

[0021] Figure 7 Is Figure 1 A top view of another embodiment of the support member that can be used in the device;

[0022] Figure 8 Is Figure 1 A top view of another embodiment of the support member that can be used in the device;

[0023] Figures 9 to 13 It shows the use Figure 1 Cross-sectional views of the sequential steps in the fabrication of semiconductor wafers using an apparatus; and

[0024] Figure 14 yes Figures 2 to 4 A perspective view of a substrate having a semiconductor wafer obtained at the end of the manufacturing process. Detailed Implementation

[0025] Figure 1 An apparatus 10 for growing silicon carbide wafers is shown. The apparatus 10 includes a body 12, a heater 14, an inlet pipe 16, an outlet pipe 18, a support 20 (also referred to as a "susceptor"), and a container 22, for example, in the shape of a cup.

[0026] The body 12 forms a reaction chamber 24, which defines an enclosed space in which the reaction takes place. A liner 20 and a container 22 are positioned within the reaction chamber 24. The body 12 is typically made of thermally insulating material and thermally insulates the reaction chamber 24 from the external environment.

[0027] Heater 14 is coupled to body 12 and is arranged, for example, facing reaction chamber 24. Heater 14 heats reaction chamber 24 and the items contained within reaction chamber 24 (e.g., support 20, container 22, gas, substrate, wafer, or other object or substance). Heater 14 can be manufactured in any manner. For example, heater 14 can be an induction heater comprising multiple coils; or heater 14 can be a resistance heater or other type of heating device, the resistance heater comprising a resistor coated with carbide.

[0028] Inlet conduit 16 provides a fluid path from the external environment of device 10 to reaction chamber 24, and as discussed below, inlet conduit 16 can be used to introduce precursors and gases into reaction chamber 24.

[0029] The outlet conduit 18 provides a fluid path from the reaction chamber 24 to the outside of the device 10. As discussed below, the outlet conduit 18 can also be used to discharge the reaction gases formed in the reaction chamber 24.

[0030] Specifically, in device 10, the reaction chamber 24 is of the horizontal flow type. For this purpose, for example... Figure 1 As shown, the inlet pipe 16 and the outlet pipe 18 are horizontally aligned with each other, and the gas flows longitudinally along the top surface of the liner 20.

[0031] The support 20 is disposed above the container 22 and within the reaction chamber 24. Within the reaction chamber 24, the support 20 forms a platform for receiving and holding a substrate or wafer. Specifically, as discussed below, during the fabrication of a SiC wafer, a silicon substrate is disposed on the support 20.

[0032] See below for reference Figures 2 to 7 As discussed in detail, the support 20 includes a frame 26 positioned above and supported by the container 22 to hold the substrate to be processed, which is here a monocrystalline silicon substrate, as referenced. Figures 9-13 As discussed in detail; the support 20 also includes an opening 28 surrounded and defined by a frame 26, and a plurality of arms 30 extending from the frame 26 toward the inside of the opening 28 for supporting the silicon substrate thereon.

[0033] Container 22 is arranged in reaction chamber 24, directly below liner 20. Liner 20 rests on container 22 such that material (molten silicon) discharged through opening 28 of liner 20 during operation of apparatus 10 can be collected by container 22. Container 22 includes a base 32 and sidewalls 34. Base 32 extends directly below opening 28 and arm 30 of liner 20. Base 32 supports sponge 33, as described in US 2018 / 0090350 cited above. Sidewalls 34 of container 22 are arranged directly below frame 26 of liner 20.

[0034] Figures 2 to 6 A support 20 that can be used in device 10 is shown. Figure 2 This is a top view of one embodiment of the support 20. Figure 3 This is a perspective view from above the support member 20. Figure 4 This is an enlarged perspective view of the details of the support member 20. Figure 5 It is along Figure 2 The cross section of the support member 20 is taken by the section line VV. Figure 6 It is along Figure 2 The section VI-VI is a section taken through a portion of the support member 20.

[0035] In detail, as mentioned above, the support 20 includes a frame 26, an opening 28 and a plurality of arms 30, which are provided as a single piece.

[0036] The frame 26 has a generally annular shape, defined externally by an outer wall 26A, internally by an inner wall 26B, top by a top surface 26C, and bottom by a bottom surface 26D. Here, the outer wall 26A is cylindrical and has a diameter associated with the reaction chamber 24; the inner wall 26B has a generally cylindrical shape, and its diameter depends on the size of the wafer to be obtained, as explained below, being only slightly larger than the wafer diameter. The bottom surface 26D is supported by the container 22, and the top surface 26C, opposite the bottom surface 26D, defines a reference plane here. In one embodiment, depending on the reaction chamber 24 used, the frame 26 also has a constant height H. F And it is usually less than 1cm, for example less than 0.5cm.

[0037] The frame 26 also has a plurality of protrusions 40, which extend radially from the inside of the opening 28 toward the center and at a consistent distance from each other. For example, in Figures 2-6 In one embodiment, the frame 26 has eight protrusions 40, each protrusion 40 being defined by arched walls 40A and transverse walls 40B extending between the arched walls 40A, the arched walls 40A having a convex surface facing the opening 28. The protrusions 40 here have the same thickness as the frame 26. The transverse walls 40B (having a planar or slightly arched shape) as a whole define a generally cylindrical virtual wall whose diameter is substantially equal to or at most slightly larger than the diameter of the semiconductor wafer to be grown (e.g., 5 μm to 10 μm larger than the diameter of the semiconductor wafer), as explained below.

[0038] The protrusion 40 may be omitted, in which case the columnar wall formed by the surface portion 40A coincides with the inner wall 26B of the frame.

[0039] Arm 30 is rod-shaped and linear, extending radially toward the center of opening 28 from protrusions 40 (one cantilever per protrusion) in a cantilever manner, and arm 30 has a free end 31 suspended above container 22. More specifically, here, as... Figure 6 As shown, arm 30 has a cross-section shaped as a non-equilateral pentagon (according to a plane parallel to a plane tangent to the outer wall 26A and inner wall 26B of frame 26). Specifically, the cross-section of arm 30 is formed here by a top portion 30A having a triangular shape and a bottom portion 30B having an inverted trapezoidal shape (where a major base forms the triangular base of the top portion 30A). In practice, the top portion 30A of each arm 30 is defined by two top inclined sides 41, 42, and the bottom portion 30B of each arm 30 is defined by two bottom inclined sides 45, 46, and a bottom side or base 47. The two top inclined sides 41, 42 of each arm 30 (in Figure 6In the ideal representation, the arm 30 joins along the vertex or vertex line 43, although in the actual embodiment, the arm 30 has a more or less rounded vertex portion surface at the top.

[0040] In the illustrated embodiment, the top inclined sides 41 and 42 have an inclination angle α (relative to the plane passing through the base of the top portion 30A and the base of the bottom portion 30B), which is smaller than the inclination angle (inclination angle β) of the bottom inclined sides 45 and 46, thereby facilitating the flow of molten material, as referenced below. Figures 9-13 The manufacturing process is described in detail in the text.

[0041] In one embodiment, in the longitudinal section, along the top line 43 ( Figure 5 As shown in the diagram, arm 30 has a constant height H. A Height H A The height H of the frame is less than 26. F In particular, as will be discussed in detail below, the distance d = H F -H A Approximately equal to the height or thickness of the substrate to be inserted into the frame 26 (e.g., 5 μm to 10 μm smaller or larger than the height of the substrate). For example, the distance d can be at least 60 μm-70 μm, and in particular, the distance d can be included between 200 μm and 300 μm.

[0042] Furthermore, in one embodiment, the arms 30 all have the same length L starting from the protrusion 40.

[0043] Specifically, the arm 30 may have a length L, which is between 11 mm and 13 mm, for example, approximately 12 mm; and a height H. A Depending on the geometry of the reaction chamber, and the height H A For example, it is included between 0.3cm and 0.7cm, specifically approximately 0.5cm; the height H1 of the top portion 30A is greater than the height H2 of the bottom portion 30B; the maximum tilt angles α and β are subject to the limitations imposed by the manufacturer, wherein the sum of α + β can be included between 110 degrees and 150 degrees (wherein, as mentioned above, β > α in general).

[0044] The tip line 43 of arm 30 defines a virtual resting surface 44, which, together with the wall defined by the side surface 40B of protrusion 40, forms a lowered seat 48 for the semiconductor wafer to be grown, as referenced below. Figures 9-13 A detailed explanation.

[0045] The support 20, and especially the arm 30, may be coated with a coating that resists the adhesion of any possible material (in particular, molten silicon, as discussed below). For example, the coating may be silicon carbide.

[0046] Figure 7 Is Figure 1 A top view of another embodiment of the support member used in the device. Specifically, Figure 7 A substrate 120 is shown, which is designed for manufacturing 6″ diameter wafers. Figure 7 The support 120 has a similar Figure 2 The support 20 has a similar overall structure, in which the arm 130 is oriented toward the interior of the opening (designated here by 128), but the opening 128, and in particular the columnar wall formed by the surface portion of the protrusion (here, 140) (designated here by 140A), has a larger size to accommodate the wafer.

[0047] Figure 8 Is Figure 1 A top view of another embodiment of the support member that can be used in the device. In particular, Figure 8 A support 220 is shown, which has a similar design to... Figure 2 The support 220 has a similar structure to the support 20. For example, the support 220 includes an arm 230 extending from the frame 226 and toward the center 228. However, with Figure 2 Compared to support 20, the arm 230 of support 220 is shorter in length than the arm 30 of support 20. In one embodiment, each arm of arm 230 has a length L, which is between 4 mm and 11 mm. Additionally, compared to... Figure 2 Compared to the support 20, the support 220 does not include a protrusion (e.g., protrusion 40) extending radially from the inside of the opening 228 towards the center. Instead, the arm 230 is directly attached to and extends from the inner wall 226B of the frame 226. The reduced length of the arm 230 and the removal of the protrusion compared to the support 20 allow for the fabrication of larger wafers.

[0048] Figures 9 to 13 It shows the use of Figure 1 This is an embodiment of the process of manufacturing silicon carbide wafers (specifically, SiC-3C wafers) using apparatus 10. For simplicity, the body 12, heater 14, inlet pipe 16, and outlet pipe 18 are not shown in these figures. Furthermore, again for simplicity, reference will be made to... Figures 2-6 The support 20, but the content mentioned also applies to the support 20. Figure 7 Supporter 120.

[0049] In detail ( Figure 9The substrate 58 of the first material (here, a silicon substrate) is positioned in the reaction chamber 24 and, more precisely, in the seat 48 of the support 20. The substrate 58 is inserted (almost forced fitted) into the seat 48, wherein the edge 58A of the substrate 58 itself contacts the surface portion 40B of the protrusion 40 on the arm 30, such that the bottom surface 58B of the substrate 58 contacts the top tip 43 of the top portion 30A of the arm 30 on the virtual resting surface 44.

[0050] The substrate 58 has the thinnest possible thickness that is compatible with brittleness. For example, the substrate 58 may have a thickness of at least 60 μm-70 μm, and more particularly, between 200 μm and 300 μm.

[0051] As mentioned above, since the distance d between the virtual shelving surface 44 and the reference plane 26C is approximately equal to the thickness of the substrate 58, the top surface of the substrate 58 is configured to be approximately aligned with the reference plane formed by the top surface 26C of the frame 26, and the substrate 58 does not substantially protrude from the opening 28 in height.

[0052] The substrate 58 typically has a crystalline structure. Furthermore, in this step, the reaction chamber 24 is at room temperature.

[0053] Once the substrate 58 is positioned in the support 20, the reaction chamber 24 is sealed and heated to a first temperature by the heater 14. For example, the first temperature can be between 450 degrees Celsius and 550 degrees Celsius. Furthermore, a first pressure level is set in the reaction chamber 24, for example, including a pressure of 8 × 10⁻⁶. -5 bar with 12×10 -5 Between bars.

[0054] After the reaction chamber 24 has been heated to a first temperature, the reaction chamber 24 is raised to a second temperature higher than the first temperature. For example, the second temperature may be between 1050 degrees Celsius and 1150 degrees Celsius. In addition, a second pressure level is set in the reaction chamber 24, which is higher than the first pressure level, and the second pressure level is, for example, between 75 mbar and 125 mbar.

[0055] For the remainder of the process, reaction chamber 24 is maintained at the second pressure level.

[0056] After the reaction chamber 24 has been heated to a second temperature, the substrate 58 is immersed in hydrogen (H2). Hydrogen is introduced into the reaction chamber 24 through inlet pipe 16. Furthermore, the substrate 58 undergoes a carbonization operation by introducing a carbon-based precursor into the reaction chamber 24 through inlet pipe 16. The carbon-based precursor carbonizes the surface silicon atoms of the substrate 58 to form a thin SiC layer, such as 3C-SiC, with a thickness, for example, in a region of a few nanometers. This is commonly referred to as ramp carbonization. As will be discussed below, the thin SiC layer acts as a seed for the growth of SiC.

[0057] Then, the reaction chamber 24 is heated by the heater 14 to a third temperature higher than the second temperature. For example, the third temperature is between 1340 degrees Celsius and 1400 degrees Celsius.

[0058] Refer again Figure 9 When the reaction chamber 24 reaches the third temperature, or after it has reached the third temperature, the carbon-based precursor and the silicon-based precursor are introduced into the reaction chamber 24 through the inlet pipe 16.

[0059] In this step, since the substrate 58 is arranged within the holder 48, with the top surface of the substrate 58 flush with the top surface 26C of the frame 26, the gas flow overlaps with the substrate 58 (or the wafer being grown) in a generally laminar motion. This allows for more uniform gas flow and a more constant temperature distribution compared to known devices.

[0060] The constant temperature distribution is also advantageous because in this step, as in the subsequent growth step and in the initial heating step, the substrate 20 is rotated within the reaction chamber 24 in a manner known per se and not shown. In this way, the substrate 58 is overlapped by the introduced gas from the entire perimeter, and thus overlapped in the most uniform way possible during growth.

[0061] Therefore, as Figure 10 As shown, the first SiC layer 60 is grown epitaxially starting from a thin SiC layer. This step is typically defined as heteroepitaxial growth.

[0062] Next, the flow of H2 through inlet pipe 16 is maintained in reaction chamber 24, and the melting process is carried out. Specifically, reaction chamber 24 is heated by heater 14 to a fourth temperature, which is higher than the melting point of substrate 58 and lower than the melting point of first SiC layer 60. For example, the fourth temperature is between 1550 degrees Celsius and 1650 degrees Celsius. Therefore, as... Figure 11 As shown, substrate 58 is melted and deposited in container 22, where it is absorbed by sponge 33. Specifically, the molten silicon from substrate 58 (in...) Figure 11The molten silicon (as specified by 66) flows along the top inclined sides 41, 42 of the arm 30, along the bottom inclined sides 45, 46 of the arm 30, and drips from the liner 20 onto the bottom of the container 22, where it is collected and absorbed by the sponge 33.

[0063] In this step, the minimum contact area between the support 20 and the substrate 58 (at the top 43 of the top portion 30A of the arm 30), and the inclination of the top and bottom inclined sides 41, 42, 45, 46, facilitate the flow of molten silicon 66 from the substrate 58. In effect, the surface tension between the support 20 and the molten silicon 66 decreases as the substrate 58 melts. Furthermore, the presence of the bottom inclined sides 45, 46 facilitates the direct downward dripping of molten silicon 66 from the top inclined sides 41, 42. Therefore, the molten silicon 66 is less likely to adhere to or attach to the arm 30; instead, it tends to detach from the support 20 and flow towards the bottom of the container 22.

[0064] The fact that the top inclined sides 41 and 42 extend through the length of the arm 30 allows the molten silicon 66 to be separated from the entire bottom surface 58B of the substrate 58.

[0065] The reaction chamber 24 can be maintained at the fourth temperature until all the substrates 58 are removed from the first SiC layer 60.

[0066] Alternative locations, such as Figure 11 As shown, the fourth temperature of the reaction chamber 24 can be maintained until a small portion or thin residual layer 70 of the substrate 58 remains on the support 20. In this embodiment, as referenced below... Figure 13 As discussed, the residual layer 70 of substrate 58 is removed by a chemical etching process.

[0067] exist Figure 12 In this process, silicon-based and carbon-based precursors are introduced into the reaction chamber 24 through inlet pipe 16. Therefore, the first SiC layer 60 continues to grow in thickness; that is, a second SiC layer 68 begins to grow on the first SiC layer 60. This step is commonly referred to as homoepitaxial growth. The silicon-based and carbon-based precursors may be supplied during the substrate 58 melting step. Alternatively, the silicon-based and carbon-based precursors may be supplied after the substrate 58 melting process is complete.

[0068] When the second SiC layer 68 reaches the desired thickness, the flow of silicon-based and carbon-based precursors is stopped. This is achieved through outlet pipe 18 ( Figure 1 Remove any possible reactive gases from reaction chamber 24.

[0069] As previously mentioned, if the SiC wafer contains residual portions 70 of the substrate 58, these residual portions are removed via a chemical etching process during the growth of the second SiC layer 68 or at the end of such growth. In this case, a chemical etching gas, such as hydrochloric acid (HCl), is introduced through inlet pipe 16 ( Figure 1 The residual portion 70 of the substrate 58, which is recoupled to the first SiC layer 60, is thus introduced into the reaction chamber 24. Therefore, the residual portion 70 of the substrate 58, which is recoupled to the first SiC layer 60, is removed by chemical etching gas and typically exits through the outlet pipe 18. Figure 13 ) was removed.

[0070] After the residual portion 70 of the substrate 58 has been removed, the reaction chamber 24 is shut off, ventilated, and returned to a lower temperature (e.g., room temperature). The resulting SiC wafer 72 can then be immersed in H2 or Ar.

[0071] Figure 13 The SiC wafer 72 thus obtained on the substrate 20 is shown.

[0072] Therefore, by using the described apparatus and process, since the frame 26 is very close to the growing wafer and the wafer does not initially protrude from the support at the top, a better temperature distribution and reduced flow instability can be achieved, enabling the growth of substantially single-crystal SiC wafers without polycrystalline edge regions over the entire diameter of the SiC wafer.

[0073] Furthermore, compared to known solutions, silicon separation can occur in a more reliable and complete manner thanks to the shape of the arms 30 and their limited number.

[0074] Therefore, it becomes possible to manufacture large-size SiC wafers, even larger than 6″, for example, 8″, up to 12″, while the process and equipment are also reliably and advantageously used to manufacture smaller-size wafers, such as 2″, 4″ and 6″ wafers.

[0075] Finally, it is apparent that modifications and variations can be made to the apparatus and processes described and illustrated herein without departing from the scope of this disclosure. For example, the various embodiments described can be combined to provide alternative solutions.

[0076] The above embodiments can be combined to provide other embodiments.

[0077] These and other changes can be made to the embodiments based on the detailed description above. Generally, the terminology used in the following claims should not be construed as limiting the claims to the specific embodiments disclosed in the specification and claims, but should be interpreted to include all possible embodiments and the full scope of equivalents conferred by these claims. Therefore, the claims are not limited to this disclosure.

Claims

1. An apparatus comprising: chamber; Collection container, in the chamber; as well as Support member, within the chamber and above the container, The support includes a frame, an opening surrounded by the frame, a plurality of arms, and a seat within the opening. The frame has a first surface and a second surface that are opposite to each other. The first surface of the frame faces the collection container. The arm is a cantilever rod that extends from the frame into the opening. Each of the arms has a maximum height smaller than the maximum height of the frame, and each of the arms has a resting edge. The resting edge of the arm defines a resting surface, which is at a level lower than the second surface of the frame. The seat has a bottom formed by the resting surface.

2. The apparatus of claim 1, wherein the resting surface is positioned at a distance from the second surface, the distance being substantially equal to the thickness of the substrate to be inserted into the seat during use.

3. The apparatus of claim 1, wherein the resting surface is positioned at a distance from the second surface.

4. The apparatus of claim 1, wherein each of the arms includes an upper portion defined by at least one inclined side, and the inclined side of each arm has a non-zero inclination relative to the resting surface.

5. The device of claim 1, wherein each of the arms includes an upper portion defined by a pair of upwardly inclined sides that are continuous and intersect to form a apex.

6. The apparatus of claim 5, wherein each of the arms includes a lower portion defined by a pair of downwardly inclined sides.

7. The apparatus of claim 6, wherein each of the arms has a pentagonal cross-section.

8. The apparatus of claim 6, wherein the lower inclined side has a greater inclination than the upper inclined side relative to a plane parallel to the resting surface.

9. The apparatus according to claim 1, further comprising: Multiple protrusions extend from the frame into the opening. Each of the plurality of protrusions has a connecting wall and a transverse wall, the connecting wall extending laterally from the frame and the transverse wall extending between the connecting walls. The transverse wall together with the resting surface forms the seat. Each of the arms extends from a corresponding transverse wall.

10. A method comprising: Position the substrate of the first material in the device. The device includes a chamber, a collection container within the chamber, and a support within the chamber and above the container. The support includes a frame, an opening surrounded by the frame, a plurality of arms, and a seat within the opening. The frame has a first surface and a second surface that are opposite to each other. The first surface of the frame faces the collection container. The arm is a cantilever rod that extends from the frame into the opening. Each of the arms has a maximum height smaller than the maximum height of the frame, and each of the arms has a resting edge. The resting edge of the arm defines a resting surface, which is at a level lower than the second surface of the frame. The seat has a bottom formed by the resting surface. The substrate is positioned in the seat and is substantially flush with the frame; A layer of a second material is formed on the substrate, the layer of the second material having a first thickness; By melting at least one first portion of the substrate, the first portion of the substrate is successively separated from the layer of the second material; as well as The layer of the second material is grown until the layer of the second material has a second thickness, which is greater than the first thickness.

11. The method of claim 10, further comprising: After the layer of the second material is grown, the second portion of the substrate is separated from the layer of the second material by chemical etching.

12. The method of claim 10, wherein the second material comprises silicon carbide, and the first material comprises silicon.

13. A support member, comprising: The frame includes a first surface and a second surface, the second surface being opposite to the first surface and the first surface and the second surface being spaced apart by a first distance; An opening within the frame; as well as Multiple arms extend into the opening, each of the multiple arms cantilevered from the frame, each of the multiple arms including a base, a first angled surface, a second angled surface, and a tip, the first angled surface and the second angled surface forming the tip, the base and the tip being spaced apart by a second distance, the second distance being smaller than the first distance. The top is positioned below the first surface of the frame.

14. The support of claim 13, wherein each of the plurality of arms includes a third angled surface and a fourth angled surface, the third angled surface coupling the first angled surface to the base, and the fourth angled surface coupling the second angled surface to the base.

15. The support member of claim 14, wherein the angle between the first angled surface and a plane is smaller than the angle between the plane and the third angled surface, and the plane extends through the plurality of arms and is parallel to the first surface of the frame.

16. The support member of claim 13, wherein the base of the plurality of arms is coplanar with the second surface of the frame.

17. The support member of claim 13, wherein the plurality of arms extend from the frame toward the center of the opening.

18. The support of claim 13, wherein the difference between the first distance and the second distance is substantially equal to the thickness of the substrate to be positioned on the plurality of arms.

19. The support member according to claim 13, further comprising: Multiple protrusions physically couple multiple arms to the frame, the multiple arms extending from the sidewalls of the multiple protrusions toward the center of the opening.

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