Abstract: In a method for manufacturing a reformed SiC wafer 41 (a surface treatment method for a SiC wafer) having its surface that is reformed by processing an untreated SiC wafer 40 before formation of an epitaxial layer 42, the method includes a surface reforming step as described below. That is, the untreated SiC wafer 40 includes BPDs as dislocations parallel to an inside of a (0001) face, and TEDs. Property of the surface of the untreated SiC wafer 40 is changed so as to have higher rate in which portions having BPDs on the surface of the untreated SiC wafer 40 propagate as TEDs at a time of forming the epitaxial layer 42.

Abstract: An object is to provide a SiC wafer in which a detection rate of an optical sensor can improved and a SiC wafer manufacturing method. The method includes: a satin finishing process S141 of satin-finishing at least a back surface 22 of a SiC wafer 20; an etching process 21 of etching at least the back surface 22 of the SiC wafer 20 by heating under Si vapor pressure after the satin finishing process S141; and a mirror surface processing process S31 of mirror-processing a main surface 21 of the SiC wafer 20 after the etching process S21. Accordingly, it is possible to obtain a SiC wafer having the mirror-finished main surface 21 and the satin-finished back surface 22.

Abstract: A heat treatment container (1) is provided with support members (6) for supporting a disc-shaped SiC substrate (2), which is an object, at a time of an etching treatment of the SiC substrate (2). Each of the support members (6) has an inclined surface (6F) for supporting a lower surface end (2E) of the SiC substrate (2), the inclined surface being inclined so as to increasingly approach the centerline of the SiC substrate (2) going downward. More specifically, each of the support members (6) is formed in a conical shape with a diameter that increases going downward, and a conical surface which is the peripheral surface of each supporting member forms the inclined surface (6F). A vertically-middle section of the inclined surface (6F) contacts the lower surface end (2E) of the SiC substrate (2).

Abstract: Provided is a surface treatment method for a SiC substrate (40), the method being capable of controlling whether to generate a step bunching or the type of step bunching that is generated. In the surface treatment method in which the surface of the SiC substrate (40) is etched by heating the SiC substrate (40) under Si vapor pressure, an etching mode and an etching depth which are determined at least on the basis of an etching rate, are controlled to etch the SiC substrate (40), so that a surface pattern of the SiC substrate (40) after etching treatment is controlled.

Abstract: In a method for manufacturing a reformed SiC wafer 41 (a surface treatment method for a SiC wafer) having its surface that is reformed by processing an untreated SiC wafer 40 before formation of an epitaxial layer 42, the method includes a surface reforming step as described below. That is, the untreated SiC wafer 40 includes BPDs as dislocations parallel to an inside of a (0001) face, and TEDs. Property of the surface of the untreated SiC wafer 40 is changed so as to have higher rate in which portions having BPDs on the surface of the untreated SiC wafer 40 propagate as TEDs at a time of forming the epitaxial layer 42.

Abstract: Provided is a method for controlling the rate of etching of a SiC substrate based on a composition of a storing container. The etching method of the present invention is for etching the SiC substrate by heating the SiC substrate under Si vapor pressure, in a state where the SiC substrate is stored in a crucible. The crucible is formed of a tantalum metal, and has a tantalum carbide layer provided on an internal space side of the tantalum metal, and a tantalum silicide layer provided on the side further toward the internal space side than the tantalum carbide layer. The rate of etching of the SiC substrate is controlled based on difference in a composition of the tantalum silicide layer.

Abstract: Provided is an inexpensive seed material for liquid phase epitaxial growth of silicon carbide. A seed material 12 for liquid phase epitaxial growth of a monocrystalline silicon carbide includes a surface layer containing a polycrystalline silicon carbide with a 3C crystal polymorph. Upon X-ray diffraction of the surface layer thereof, a first-order diffraction peak corresponding to a (111) crystal plane is observed as a diffraction peak corresponding to the polycrystalline silicon carbide with a 3C crystal polymorph but no other first-order diffraction peak having a diffraction intensity of 10% or more of the diffraction intensity of the first-order diffraction peak corresponding to the (111) crystal plane is observed.

Abstract: Provided is a method for producing high-purity SiC single crystal, which is applicable to a process of growing SiC single crystal through a solution growth method. This method is for producing SiC single crystal and includes growing, through a solution growth method, an epitaxial layer on a seed material, at least a surface of which is made of SiC, wherein the SiC single crystal is grown so that impurity concentrations therein measured by secondary ion mass spectrometry are very small. Also provided is a housing container for growing SiC single crystal through a solution growth method using a Si melt, including a feed material that is disposed on at least a surface of the housing container and adds, to the Si melt, an additional material that is SiC and/or C. Performing the solution growth method using this housing container can produce high-purity SiC single crystal without any special treatment.

Abstract: A heat treatment container (1) is provided with support members (6) for supporting a disc-shaped SiC substrate (2), which is an object, at a time of an etching treatment of the SiC substrate (2). Each of the support members (6) has an inclined surface (6F) for supporting a lower surface end (2E) of the SiC substrate (2), the inclined surface being inclined so as to increasingly approach the centerline of the SiC substrate (2) going downward. More specifically, each of the support members (6) is formed in a conical shape with a diameter that increases going downward, and a conical surface which is the peripheral surface of each supporting member forms the inclined surface (6F). A vertically-middle section of the inclined surface (6F) contacts the lower surface end (2E) of the SiC substrate (2).

Abstract: Provided is a SiC substrate treatment method for, with respect to a SiC substrate (40) that has, on its surface, grooves (41), activating ions while preventing roughening of the surface of the substrate. In the method, an ion activation treatment in which the SiC substrate (40) is heated under Si vapor pressure is performed to the SiC substrate (40) has, on its surface, an ion implantation region (46) in which ions have been implanted, and has the grooves (41) provided in a region including at least the ion implantation region (46), thereby ions that are implanted in the SiC substrate (40) is activated while etching the surface of the substrate.

Abstract: This method for estimating the depth of latent scratches in SiC substrates includes an etching step, a measurement step, and an estimation step. In the etching step, a SiC substrate in which at least the surface is formed from single crystal SiC, and which has been subjected to machining, is subjected to heat treatment under Si atmosphere to etch the surface of the SiC substrate. In the measurement step, the surface roughness or the residual stress of the SiC substrate which has been subjected to the etching step is measured. In the estimation step, the depth of latent scratches or the presence or absence of latent scratches in the SiC substrate before the etching step are estimated on the basis of the results obtained in the measurement step.

Abstract: Provided is a method for manufacturing a thin SiC wafer by which a SiC wafer is thinned using a method without generating crack or the like, the method in which polishing after adjusting the thickness of the SiC wafer can be omitted. The method for manufacturing the thin SiC wafer 40 includes a thinning step. In the thinning step, the thickness of the SiC wafer 40 can be decreased to 100 ?m or less by performing the Si vapor pressure etching in which the surface of the SiC wafer 40 is etched by heating the SiC wafer 40 after cutting out of an ingot 4 under Si vapor pressure.

Abstract: Provided is a surface treatment method for a SiC substrate (40), the method being capable of controlling whether to generate a step bunching or the type of step bunching that is generated. In the surface treatment method in which the surface of the SiC substrate (40) is etched by heating the SiC substrate (40) under Si vapor pressure, an etching mode and an etching depth which are determined at least on the basis of an etching rate, are controlled to etch the SiC substrate (40), so that a surface pattern of the SiC substrate (40) after etching treatment is controlled.

Abstract: Provided is a method for controlling the rate of etching of a SiC substrate based on a composition of a storing container. The etching method of the present invention is for etching the SiC substrate by heating the SiC substrate under Si vapor pressure, in a state where the SiC substrate is stored in a crucible. The crucible is formed of a tantalum metal, and has a tantalum carbide layer provided on an internal space side of the tantalum metal, and a tantalum silicide layer provided on the side further toward the internal space side than the tantalum carbide layer. The rate of etching of the SiC substrate is controlled based on difference in a composition of the tantalum silicide layer.

Abstract: Provided is a SiC substrate treatment method for, with respect to a SiC substrate (40) that has, on its surface, grooves (41), activating ions while preventing roughening of the surface of the substrate. In the method, an ion activation treatment in which the SiC substrate (40) is heated under Si vapor pressure is performed to the SiC substrate (40) has, on its surface, an ion implantation region (46) in which ions have been implanted, and has the grooves (41) provided in a region including at least the ion implantation region (46), thereby ions that are implanted in the SiC substrate (40) is activated while etching the surface of the substrate.

Abstract: Provided is a method for manufacturing a thin SiC wafer by which a SiC wafer is thinned using a method without generating crack or the like, the method in which polishing after adjusting the thickness of the SiC wafer can be omitted. The method for manufacturing the thin SiC wafer 40 includes a thinning step. In the thinning step, the thickness of the SiC wafer 40 can be decreased to 100 ?m or less by performing the Si vapor pressure etching in which the surface of the SiC wafer 40 is etched by heating the SiC wafer 40 after cutting out of an ingot 4 under Si vapor pressure.

Abstract: Provided is a feed material for epitaxial growth of a monocrystalline silicon carbide capable of increasing the rate of epitaxial growth of silicon carbide. A feed material 11 for epitaxial growth of a monocrystalline silicon carbide includes a surface layer containing a polycrystalline silicon carbide with a 3C crystal polymorph. Upon X-ray diffraction of the surface layer, a diffraction peak corresponding to a (111) crystal plane and a diffraction peak other than the diffraction peak corresponding to the (111) crystal plane are observed as diffraction peaks corresponding to the polycrystalline silicon carbide with a 3C crystal polymorph.

Abstract: The present invention is to provide a storing container wherein Si does not drop onto a single crystal SiC substrate, and Si pressure distribution in an internal space can be made uniform. This storing container stores therein a single crystal SiC substrate to be etched by means of a heat treatment under Si vapor pressure. The storing container is formed of a tantalum metal, and has a tantalum carbide layer provided on an internal space side, and a tantalum silicide layer provided on the side further toward the internal space side than the tantalum carbide layer. The tantalum silicide layer supplies Si to the internal space. Furthermore, the tantalum silicide layer is different from adhered Si, and does not melt and drop.

Abstract: Provided is a heat treatment container having a small size and capable of efficiently performing a heat treatment on a SiC substrate. A heat treatment container is a container for a heat treatment on a SiC substrate 40 under Si vapor pressure. The SiC substrate 40 is made of, at least in a surface thereof, single crystal SiC. The heat treatment container includes a container part 30 and a substrate holder 50. The container part 30 includes an internal space 33 in which Si vapor pressure is caused. The internal space 33 is partially open. The substrate holder 50 is able to support the SiC substrate 40. When the substrate holder 50 supports the SiC substrate 40, an open portion of the container part 30 is covered so that the internal space 33 is hermetically sealed.

Abstract: When a SiC substrate (40) after performing mechanical treatment is heat-treated under SiC atmosphere to etch the SiC substrate (40), the etching rate is controlled by adjusting the inert gas pressure around the periphery of the SiC substrate (40). As a result, when latent scratches or the like exist in the SiC substrate (40), the latent scratches or the like can be removed. Accordingly, the surface of the SiC substrate (40) does not become rough, even if epitaxial growth and heat treatment and the like are performed. This can manufacture high-quality SiC substrates.