Method for manufacturing multiple polycrystalline silicon carbide substrates

Abstract

The present invention is a method for manufacturing multiple polycrystalline silicon carbide substrates (200), comprising the following steps, namely: The process involves forming a multilayer structure by alternately depositing multiple polycrystalline silicon carbide layers (20, 21, 22, 23, 24) and multiple isolation layers (30, 31, 32, 33) on at least one surface of a temporary support substrate (10), The steps include removing the temporary substrate (10) and each separation layer (30, 31, 32, 33) to peel off each polycrystalline silicon carbide layer (20, 21, 22, 23, 24) from the multilayer structure and form each polycrystalline silicon carbide substrate (200), Regarding manufacturing methods including

Description

Technical Field

[0001] The present invention relates to the field of manufacturing silicon carbide substrates for forming electronic components. More specifically, the present invention proposes a method for simultaneously manufacturing a plurality of polycrystalline silicon carbide substrates.

Background Art

[0002] For the formation of electronic components, polycrystalline silicon carbide (p-SiC) substrates having a layer of a single crystal material such as monocrystalline silicon carbide (m-SiC), gallium nitride (GaN), gallium oxide (Ga2O3), or diamond on the surface are often used.

[0003] In order to ensure good mechanical and electrical contact between the support substrate and the single crystal layer, the p-SiC-based substrate must have a homogeneous crystal quality and a smooth surface. Usually, the production of such a base substrate includes chemically vapor growing a thick layer of p-SiC on a temporary substrate, such as a graphite substrate, and then removing the temporary substrate to separate the thick p-SiC layer.

[0004] Next, a substantial thickness portion is removed from the p-SiC layer in order to retain only the thin portion having a crystal quality suitable for the deposition of the m-SiC layer. Thus, the thick p-SiC layer usually has an initial thickness of 900 to 3000 μm. After removing the portion with poor crystal quality, a thickness of usually about 350 μm is retained, and at this thickness, the crystal quality for accepting the m-SiC layer is appropriate.

[0005] p-SiC deposited by chemical vapor deposition (CVD) is extremely hard and difficult to cut. Its polycrystalline structure and crystal grains pose a high risk of breakage during cutting. Furthermore, each cut hardens the wafer surface, which must then be removed by grinding and / or polishing. This results in significant material loss. Therefore, it is difficult to fabricate p-SiC blocks of thickness corresponding to multiple base substrates and cut multiple substrates from such blocks. Consequently, each base substrate is manufactured individually.

[0006] This process is time-consuming and labor-intensive. It also consumes a large amount of p-SiC, but this p-SiC is removed before the m-SiC layer is deposited and therefore not used in the manufactured substrate. [Overview of the Initiative]

[0007] One objective of the present invention is to provide a method for simultaneously manufacturing multiple polycrystalline silicon carbide substrates that is more economical than existing methods.

[0008] For this purpose, the present invention provides a method for manufacturing multiple polycrystalline silicon carbide substrates, comprising the following steps, namely: - A step of forming a multilayer structure by alternately depositing multiple polycrystalline silicon carbide layers and multiple isolation layers on at least one surface of a temporary support substrate. The steps include: removing the temporary substrate and each separation layer to peel off each polycrystalline silicon carbide layer from the multilayer structure and form each polycrystalline silicon carbide substrate; We propose a manufacturing method that includes this.

[0009] By using a separation layer, the polycrystalline silicon carbide layer can be easily separated without the risk of damage.

[0010] In certain embodiments, the deposition of each polycrystalline silicon carbide layer and each isolation layer is achieved simultaneously across the entire outer surface of the temporary support substrate and / or their respective sublayers.

[0011] The deposition extends to the outer periphery of the substrate; therefore, by using the two free surfaces of the temporary support substrate, the yield of this method can be increased.

[0012] Next, the method further includes the step of removing the edges of the multilayer structure after the deposition of the last polycrystalline silicon carbide layer in order to expose the edges of the temporary support substrate.

[0013] In a particularly preferred method, the temporary support substrate may be made of graphite.

[0014] Particularly preferred are each separation layer made of carbon, graphite, silicon, or silicon nitride (Si3N4).

[0015] In certain embodiments, the removal of the temporary support substrate is performed by combustion under an oxygen stream at a temperature of 700 to 1100°C, preferably 800 to 900°C.

[0016] In certain embodiments, the removal of each separation layer is carried out by combustion.

[0017] In other embodiments, each separation layer is removed by sawing, chemical etching, or laser cutting.

[0018] In certain embodiments, the thickness of the temporary support substrate is 1 to 15 mm.

[0019] In certain embodiments, the thickness of each polycrystalline silicon carbide layer is 300 to 1200 μm.

[0020] In certain embodiments, the thickness of each separation layer is 1 to 50 μm.

[0021] In other embodiments, the thickness of each separation layer is 1 to 500 nm.

[0022] In certain embodiments, the thickness of each separation layer increases with the distance from the temporary support substrate.

[0023] Another subject of the present invention is a method for manufacturing a plurality of substrates each comprising a polycrystalline silicon carbide-based substrate and a layer of a single-crystalline material, · a step of implementing the above method for manufacturing each polycrystalline silicon carbide substrate; · a step of planarizing the front surface of each polycrystalline silicon carbide-based substrate; · a step of transferring a layer of a single-crystalline material onto the front surface of each polycrystalline silicon carbide-based substrate; relates to a manufacturing method sequentially including.

[0024] In certain embodiments, the step of transferring the single-crystalline material layer is the following steps, namely, · forming a weakened region by implanting atomic species into a donor substrate made of a single-crystalline material to define a single-crystalline material layer to be transferred; · bonding the donor substrate to the front surface of the base substrate; · peeling the donor substrate along the weakened region to transfer the single-crystalline material layer to the base substrate; including.

[0025] Another subject of the present invention is · a temporary support substrate, · an alternating laminate of a plurality of polycrystalline silicon carbide layers and separation layers on at least one surface of the temporary substrate, relates to an intermediate substrate provided with.

[0026] Preferably, the temporary support substrate is made of graphite.

[0027] Preferably, each separation layer is made of carbon, graphite, silicon, or silicon nitride.

[0028] Other features and advantages of the present invention will become apparent from the following detailed description with reference to the accompanying figures. [Brief explanation of the drawing]

[0029] [Figure 1] This shows the temporary support substrate. [Figure 2] A temporary support substrate having a first p-SiC layer is shown. [Figure 3] A temporary support substrate comprising a first p-SiC layer and a first isolation layer is shown. [Figure 4] This is a schematic diagram of a temporary support substrate comprising multiple p-SiC layers and multiple isolation layers. [Figure 5] This is a schematic diagram of the temporary support substrate after edge polishing. [Figure 6] Multiple polycrystalline silicon carbide substrates are shown. [Figure 7] This shows the formation of weakened regions in the donor substrate. [Figure 8] This shows the transfer of a single crystal layer onto a p-SiC base substrate. [Figure 9] This shows a substrate comprising a p-SiC base substrate and a single crystal layer on the front surface of the p-SiC base substrate. [Modes for carrying out the invention]

[0030] Figures 1 to 6 illustrate the steps of a method for manufacturing multiple silicon carbide substrates. The substrates are sequentially deposited on a temporary support substrate and separated by a separation layer. A multilayer substrate is thus manufactured and subsequently separated into multiple individual p-SiC substrates.

[0031] Temporary support board Referring to Figure 1, first, a temporary support substrate 10 is provided. Preferably, the temporary support substrate 10 is made of graphite. The temporary support substrate has two main parallel surfaces, a front surface and a back surface.

[0032] Graphite has a coefficient of thermal expansion similar to that of silicon carbide. Therefore, it is particularly suitable as a temporary support substrate material for substrate manufacturing involving high-temperature steps, such as deposition by CVD. Furthermore, graphite can be easily removed in later steps of this method, for example, by combustion or chemical corrosion.

[0033] The temporary support substrate has sufficient thickness to be self-supporting and stable enough to deposit several continuous layers without significant deformation. Preferably, the thickness of the temporary support substrate is 1 to 15 mm. The temporary support substrate has a sufficiently smooth surface that allows for the uniform deposition of several continuous layers without significant deformation of its surface. The temporary support substrate has a thermal expansion coefficient close to that of p-SiC to avoid delamination and breakage (a phenomenon called "cracking") of the substrate during high-temperature processing.

[0034] Layer deposition Referring to Figure 2, a first layer 20 of polycrystalline silicon carbide (p-SiC) is deposited on a temporary support substrate 10. The p-SiC can have any electrical resistivity suitable for the intended application. According to a preferred embodiment, the p-SiC is doped with, for example, nitrogen or phosphorus. In other embodiments, the p-SiC has high electrical resistivity.

[0035] The p-SiC is preferably deposited in the form of micrometer-sized grains, having a uniform structure and size throughout the entire thickness of the deposited layer. The term "micrometer-sized" is understood herein to mean a grain size greater than 1 μm in a plane parallel to the front surface of the temporary support substrate, i.e., perpendicular to the deposition direction of the p-SiC layer. Preferably, the grain size in the above plane is less than 100 μm. Particularly preferred, the grain size in the plane parallel to the front surface of the temporary substrate is 1 μm to 50 μm. The grain size in the deposition direction is usually larger than the size in the plane perpendicular to the deposition direction, and is usually elongated along the deposition direction of the p-SiC layer. Preferably, the p-SiC grain size in the deposition direction is less than 250 μm. Particularly preferred, the grain size in the deposition direction is 1 μm to 100 μm.

[0036] The p-SiC layer 20 is preferably deposited by CVD deposition. Exemplary and non-limiting, the p-SiC layer is deposited at a temperature of 1100–1500°C. Typically, the temporary support substrate is placed in a deposition chamber, and deposition is carried out so that the p-SiC layer extends across the entire surface of the temporary support substrate, including its periphery. In certain embodiments, the p-SiC layer is deposited on both the front and back surfaces of the temporary support substrate. In other embodiments, the p-SiC layer may be deposited on only one surface of the temporary support substrate. In either case, p-SiC may be deposited on both sides of the support substrate.

[0037] Alternatively, p-SiC may be deposited by physical vapor deposition (PVD) or physical vapor transport (PVT). p-SiC may also be deposited by liquid phase CVD, atmospheric pressure CVD, high-temperature CVD, or direct liquid injection CVD. p-SiC may also be deposited from trichlorosilane.

[0038] The thickness of the p-SiC layer corresponds to the thickness of the p-SiC substrate being manufactured and is determined by the final application of the p-SiC substrate. Such substrate thicknesses are often selected according to the dimensions of the substrate to provide a self-supporting and mechanically stable substrate. For example, a p-SiC substrate with a diameter of 150 mm (6") typically has a thickness of more than 50 μm, more preferably more than 100 μm, to be self-supporting. To manufacture such a substrate, a first layer 20 with a thickness of 300 μm to 900 μm, preferably 360 μm to 900 μm, is usually deposited. A p-SiC substrate with a diameter of 200 mm (8") typically has a thickness of 510 to 1200 μm. To manufacture such a substrate, a first layer 20 with a minimum thickness of 510 μm is usually deposited.

[0039] Regarding the subsequent layers, the thickness of each p-SiC layer is, for example, 500 μm or more for a substrate with a diameter of 150 mm, and 650 μm or more for a substrate with a diameter of 200 mm.

[0040] The maximum thickness of the p-SiC layer may be 900 μm for a substrate with a diameter of 150 mm, or 1.2 mm for a substrate with a diameter of 200 mm.

[0041] Therefore, the p-SiC substrate can be polished to optimize its surface quality and achieve the desired final thickness.

[0042] Referring to Figure 3, a separation layer 30 is then deposited on the p-SiC layer 20. The separation layer 30 may be made of carbon, graphite, silicon, silicon nitride, titanium nitride, or another material that can be easily removed from the p-SiC layer. Preferably, the deposition of the separation layer 30 is carried out in the same deposition chamber as the deposition of the p-SiC layer 20. Therefore, it is not necessary to remove the substrate from the chamber between consecutive depositions. Thus, the handling of the substrate and the risk of contamination of the boundary between the p-SiC layer 20 and the separation layer 30 are avoided. Opening the deposition chamber and potential contamination are also avoided. The thickness of the separation layer 30 may be nanometer size, e.g., 1 to 500 nm, or micrometer size, e.g., 1 to 50 μm.

[0043] A separation layer may be deposited over the entire surface of the p-SiC layer. In a particular embodiment, the separation layer is deposited only on the front surface of a temporary support substrate having a p-SiC layer on its front surface, or only on the front and back surfaces of a temporary support substrate 10 having p-SiC layers on both its front and back surfaces.

[0044] Referring to Figure 4, the p-SiC layers 20, 21, 22, 23, 24 and the separation layers 30, 31, 32, 33 are then deposited in succession to produce a multilayer structure. The two types of layers are deposited alternately to obtain a structure in which the p-SiC layers and separation layers are continuous with each other. The separation layers are always placed between two consecutive p-SiC layers. Exemplarily and non-limitingly, the last layer to be deposited, 24, is a p-SiC layer. Therefore, in a multilayer structure having n p-SiC layers, where n is an integer, n-1 separation layers are deposited. Typically, a number n of p-SiC layers, 2 to 20, preferably 5 to 15, are deposited.

[0045] Typically, each p-SiC layer and each isolation layer is deposited over the entire surface of their respective sublayers. In this way, it is possible to create a multilayer structure only on the front surface of the temporary support substrate. Alternatively, it is possible to create a multilayer structure simultaneously on both the front and back surfaces of the temporary support substrate. In a preferred embodiment, the temporary support substrate is placed in a deposition chamber, and each layer is deposited over the entire surface of the temporary support substrate, or over the entire surface of their respective sublayers.

[0046] By using both the front and back surfaces of the temporary support substrate simultaneously, the number of layers formed by a given deposition step doubles, thereby increasing the yield of this method.

[0047] Typically, during simultaneous deposition on both sides of the substrate, the material is deposited at the edges as well.

[0048] During the deposition of two layers, namely the p-SiC layer and the isolation layer, within a single chamber, there is no need to manipulate the temporary support substrate until the multilayer structure is finished. Furthermore, the process of introducing the substrate into and removing it from the deposition chamber is avoided, thereby preventing contamination of the chamber and the boundaries between each layer.

[0049] To ensure the continuity of the separation layer across the entire boundary between two consecutive p-SiC layers, the thickness of the separation layer is greater than the roughness of the p-SiC layer after each layer has been deposited.

[0050] Typically, during the deposition of multiple superimposed layers, the roughness increases continuously with the number of layers deposited, due to the fact that the roughness of each underlying layer affects the roughness of the subsequently deposited layers.

[0051] Therefore, while depositing several consecutive p-SiC layers, the thickness of the separation layer can be suitably increased along with the number of deposition cycles and the distance of each layer from the temporary support substrate. This offsets the increase in roughness and makes it possible to obtain a relatively smooth surface for the last layer deposited in this process.

[0052] It is also possible to increase the thickness of the p-SiC layer during the deposition process. Preferably, the thickness of each layer corresponds to the thickness of the manufactured substrate plus the total variation in thickness at the level of the layer directly beneath it. This makes it possible to initially offset the increase in roughness. Furthermore, by manufacturing thicker layers in rougher regions at the end of deposition, it becomes possible to perform more substantial polishing after separating the layers in order to smooth the resulting p-SiC substrate.

[0053] Therefore, for a substrate with a diameter of 150 mm, the first p-SiC layer may have a thickness of approximately 360 μm, and the last p-SiC layer may have a thickness of up to 900 μm, preferably about 500 μm. For a substrate with a diameter of 200 mm, the first p-SiC layer may have a thickness of approximately 510 μm, and the last p-SiC layer may have a thickness of up to 1200 μm, preferably about 650 μm.

[0054] Separation of p-SiC substrates After fabricating the multilayer structure, a step is taken to separate the p-SiC layers in order to form a p-SiC substrate from each p-SiC layer.

[0055] When p-SiC layers and isolation layers are deposited across the entire surface of the temporary support substrate, and / or when the edges of the temporary support substrate are covered during the deposition of the continuous layers, the edges of the multilayer structure are removed. Referring to Figure 5, the p-SiC layers and isolation layers are removed along the edges of the multilayer structure, exposing the respective layers and the edges of the temporary support substrate. Removal of material along the edges of the multilayer structure is preferably performed by mechanical trimming. In some cases, removal may be performed by laser cutting.

[0056] Next, in order to separate the SiC layers, the temporary support substrate and the isolation layer placed between each p-SiC layer are removed.

[0057] The temporary support substrate is usually removed by combustion under an oxygen stream. The combustion temperature is typically 700°C to 1100°C, preferably 800°C to 900°C.

[0058] The removal of the separation layer, such as carbon or graphite, may also be carried out by combustion. Preferably, the support substrate and the separation layer are removed in a single removal step. A single removal increases the efficiency of the method and, consequently, the yield, and avoids further combustion and heating steps.

[0059] The combustion temperature can be selected according to the material and thickness of the separation layer and may be the same as or different from the combustion temperature of the temporary support substrate. Alternatively, depending on the material, thickness, and number of separation layers, the separation layers may be removed by sawing, chemical etching, or laser cutting. These methods will be described in more detail in the section on separation layers.

[0060] The thickness of the separation layer can also be selected according to the removal technique. If the separation layer is intended to be removed by chemical corrosion or combustion, the thickness of the layer is preferably in the micrometer range to facilitate the passage of gases and chemicals used for removal and for discharging by-products obtained during removal. This method is particularly used for separation layers made of carbon, graphite, or silicon or silicon nitride.

[0061] For example, in embodiments including removal by liquid chemical corrosion for a silicon or silicon nitride separation layer, the thickness of each separation layer is preferably greater than 1 micrometer per inch in diameter, i.e., about 25 mm in diameter.

[0062] In embodiments in which removal is carried out by gas corrosion, for example by combustion of carbon and / or graphite, the thickness of each separation layer is preferably greater than 0.1 micrometers per inch in diameter, i.e., per approximately 25 mm in diameter.

[0063] In certain embodiments, the removal of the support substrate is performed in a separate step from the removal of the separation layer. For example, the removal of the temporary support substrate may be performed at a different temperature and by a different type of process than the removal of the separation layer. In particular, the temporary support substrate can be removed before the separation layer is removed. This makes it possible to subsequently process the two multilayer structures initially deposited on the two surfaces of the temporary support substrate simultaneously.

[0064] Referring to Figure 6, the p-SiC layer is separated by the removal step, forming an independent p-SiC substrate 200. Here, finishing steps such as grinding the p-SiC substrate 200 to adjust the thickness of each layer to a target thickness before polishing, polishing the substrate, heat treatment and / or surface treatment can be performed.

[0065] Thus, by depositing a multilayer structure and subsequently removing the temporary support substrate, it becomes possible to manufacture multiple p-SiC substrates simultaneously. This process achieves a higher yield than manufacturing p-SiC substrates individually, saves manufacturing time and energy, and simplifies the process.

[0066] The p-SiC substrate can then be used as a base substrate for manufacturing substrates for electronic components.

[0067] separation layer The separation layer is made of a material that can be easily removed in a later step of this method. Preferably, the material for the separation layer may be deposited in the same chamber in which the p-SiC layer is deposited. For example, the separation layer may be deposited by CVD.

[0068] The separation layers are made of a material having a surface structure similar to the crystalline structure of p-SiC in order to facilitate the deposition of other p-SiC layers after the deposition of each separation layer. The thermal expansion coefficient of the separation layers is close to that of p-SiC in order to avoid boundary stress in all steps of this method, which are performed at high temperatures. Preferably, the Young's modulus of the separation layer material is lower than that of p-SiC. For example, the separation layers may be made of carbon, graphite, silicon, or silicon nitride (Si3N4). The above materials allow for good retention at each boundary between the separation layers and the p-SiC layers. This retention facilitates the handling of the multilayer structure in the steps between the deposition and delamination of the p-SiC layers.

[0069] As described above, the thickness of the separation layer can be increased along with the number of deposition cycles and the distance of each layer from the temporary support substrate. This makes it possible to offset the increase in roughness and obtain a relatively smooth surface with respect to the outer layer.

[0070] The thickness of the separation layer is further selected to allow for easy removal of the separation layer while separating the p-SiC layer. The thickness is also determined by the material of the separation layer, the size of the substrate surface, and the removal method used. In some cases, the thickness of the separation layer is several nanometers. In other embodiments, the thickness of the separation layer may be greater, reaching values ​​up to 50 μm.

[0071] The removal technique is also selected according to the material and thickness of the separation layer.

[0072] Exemplary and non-limiting, a separation layer made of carbon or graphite, several micrometers thick, can be easily removed by combustion simultaneously with or following the temporary support substrate.

[0073] For separation layers with a thickness of several tens of micrometers, separation can be performed by wire sawing. Separation layers made of carbon or graphite are far easier to saw than bulk substrates made of p-SiC. Residue from the separation layer can be removed by complete or partial combustion and / or grinding.

[0074] Depending on the doping of the p-SiC layer, laser cutting can also be considered. For example, by selecting a laser with a wavelength that does not penetrate the separation layer but penetrates the p-SiC layer, and irradiating with such a laser, only the separation layer can be removed.

[0075] In the case of a separation layer made of silicon, a thickness of, for example, several tens of nanometers to about 1 μm can be expected. To remove the separation layer made of silicon, the multilayer structure can be placed in a bath of tetramethylammonium hydroxide (TMAH) or tetraethylammonium hydroxide (TEAH) to dissolve the silicon. This step is preferably performed after the temporary support substrate has been removed by combustion. When the separation layer is made of silicon, it is preferable to limit the temperature of the CVD step to below the melting point of silicon, 1414°C.

[0076] In other embodiments, the separation layer may be made of silicon nitride (SiN). In this case, the thickness of the separation layer is preferably several tens of nanometers to about 1 μm. To remove the separation layer made of silicon nitride, the multilayer structure can be placed in a bath of phosphoric acid (H3PO4) to dissolve the SiN and separate the p-SiC substrate. This step is preferably performed after the temporary support substrate has been removed by combustion.

[0077] Separation layers made of carbon, graphite, or silicon have the advantage that these materials are already present in the CVD deposition chamber where the silicon carbide layer is deposited. Therefore, the addition of any elements to such a chamber is avoided, thus limiting contamination of the deposition chamber and the manufactured substrate. If the p-SiC layer is doped with nitrogen, this element must also be present in the deposition chamber. In this case, the advantage of avoiding contamination also applies to silicon nitride separation layers.

[0078] Use of p-SiC substrate Referring to Figures 7 to 9, p-SiC substrates can be used to manufacture substrates for forming electronic components. Such substrates have a layer of single-crystal material on their surface, such as single-crystal silicon carbide (m-SiC), gallium nitride (GaN), gallium oxide (Ga2O3), or diamond.

[0079] After smoothing the front surface of the p-SiC substrate manufactured by the above method, a further step may be optionally performed to create a surface for transferring a single crystal layer. Next, a layer of single crystal material is transferred to the front surface of the p-SiC substrate.

[0080] For this purpose, a donor substrate 400 made of the single-crystal material is provided. Referring to Figure 7, as schematically shown by the arrows, ion species are implanted into the donor substrate 400. The ion species are, for example, hydrogen and / or helium. In this way, weakened regions 41 that define the single-crystal layer 40 to be transferred are formed.

[0081] Referring to Figure 8, the donor substrate 400, thus injected, is bonded to the p-SiC substrate 200. Bonding can be achieved by direct contact, or by interposing one or more layers made of oxides such as silicon dioxide, metals such as titanium or tungsten, and / or semiconductors or semimetals such as amorphous or crystalline silicon, or SiC. In either case, one or both surfaces may be activated, particularly by plasma or ion bombardment, to generate a dangling bond before contact with the surfaces to be bonded.

[0082] Referring to Figure 9, the donor substrate 400 is peeled along the weakened region 41, and as a result, the single crystal layer 40 is transferred to the p-SiC base substrate 200. Peeling may be initiated by heat treatment. Next, the transferred layer may be subjected to a finishing treatment to correct any defects related to the injection and to smooth the free surface of the layer.

Claims

1. A method for manufacturing multiple polycrystalline silicon carbide substrates (200), comprising the following steps, namely, The steps include forming a multilayer structure by alternately depositing a plurality of polycrystalline silicon carbide layers (20, 21, 22, 23, 24) and a plurality of isolation layers (30, 31, 32, 33) on at least one surface of a temporary support substrate (10), The steps include removing the temporary substrate (10) and each separation layer (30, 31, 32, 33) to peel off each polycrystalline silicon carbide layer (20, 21, 22, 23, 24) from the multilayer structure to form each polycrystalline silicon carbide substrate (200), A manufacturing method that includes this.

2. The manufacturing method according to claim 1, wherein the deposition of each polycrystalline silicon carbide layer (20, 21, 22, 23, 24) and each separation layer (30, 31, 32, 33) is carried out simultaneously over the entire outer surface of the temporary support substrate (10) and / or each of the lower layers.

3. The manufacturing method according to claim 2, further comprising the step of removing the end of the multilayer structure after the deposition of the last polycrystalline silicon carbide layer (24) in order to expose the end of the temporary support substrate (10).

4. The manufacturing method according to any one of claims 1 to 3, wherein the temporary support substrate (10) is made of graphite.

5. Each separation layer (30, 31, 32, 33) is made of carbon, graphite, silicon, or silicon nitride (Si ３ N ４ A manufacturing method according to any one of claims 1 to 4, which is produced by )

6. The manufacturing method according to any one of claims 1 to 5, wherein the removal of the temporary support substrate (10) is carried out by combustion under an oxygen stream at a temperature of 700 to 1100°C, preferably 800 to 900°C.

7. The manufacturing method according to claim 5, wherein the removal of each separation layer (30, 31, 32, 33) is performed by combustion.

8. The manufacturing method according to any one of claims 1 to 4, wherein the removal of each separation layer (30, 31, 32, 33) is performed by sawing, chemical etching, or laser cutting.

9. The manufacturing method according to any one of claims 1 to 8, wherein the thickness of the temporary support substrate (10) is 1 to 15 mm.

10. The manufacturing method according to any one of claims 1 to 9, wherein the thickness of each polycrystalline silicon carbide layer (20, 21, 22, 23, 24) is 300 to 1200 μm.

11. The manufacturing method according to any one of claims 1 to 10, wherein the thickness of each separation layer (30, 31, 32, 33) is 1 to 50 μm.

12. The manufacturing method according to any one of claims 1 to 10, wherein the thickness of each separation layer (30, 31, 32, 33) is 1 to 500 nm.

13. The manufacturing method according to any one of claims 1 to 12, wherein the thickness of each separation layer (30, 31, 32, 33) increases with distance from the temporary support substrate.

14. A method for manufacturing a plurality of substrates comprising a polycrystalline silicon carbide-based substrate (200) and a single-crystal material layer (40), A manufacturing method according to any one of claims 1 to 13 for manufacturing each polycrystalline silicon carbide substrate, The steps include smoothing the front surface of each polycrystalline silicon carbide base substrate (200), The steps include transferring a layer of single-crystal material (40) onto the front surface of each polycrystalline silicon carbide base substrate (200), A manufacturing method that includes the following in order.

15. The step of transferring the single-crystal material layer (40) is as follows: The process involves forming a weakened region (41) by injecting atomic species into a donor substrate (400) made of single-crystal material, thereby defining the single-crystal material layer to be transferred. The steps include: bonding the donor substrate (400) to the front surface of the base substrate (200); In order to transfer the single-crystal material layer (40) to the base substrate (200), the donor substrate (400) is peeled off along the weakened region (41), The manufacturing method according to claim 14, including

16. Temporary support substrate (10), On at least one surface of the temporary substrate (10), there is an alternating laminate of multiple polycrystalline silicon carbide layers (20, 21, 22, 23, 24) and separation layers (30, 31, 32, 33), An intermediate substrate comprising the above.

17. The intermediate substrate according to claim 16, wherein the temporary support substrate (10) is made of graphite.

18. The intermediate substrate according to claim 16 or claim 17, wherein each isolation layer (30, 31, 32, 33) is made of carbon, graphite, silicon, or silicon nitride.

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