METHOD FOR PRODUCING POLYCRYSTALLINE SILICON CARBIDE SUBSTRATE

The present invention provides a method for producing a polycrystalline silicon carbide substrate 33 capable of reducing production costs without changing the quality of the polycrystalline silicon carbide substrate.The method includes: a carbon layer forming step of forming a carbon layer 21 on a surface of a first underlying substrate 11 to produce a second underlying substrate 12; a polycrystalline silicon carbide film forming step of forming a polycrystalline silicon carbide film 31 on a surface of the second underlying substrate by a chemical vapor deposition method; a carbon layer exposing step of removing an outer peripheral edge of the polycrystalline silicon carbide film formed on the surface of the second underlying substrate to expose the carbon layer; and a polycrystalline silicon carbide film separating step of burning the exposed carbon layer in an oxygen-containing atmosphere and separating the polycrystalline silicon carbide film from the second underlying substrate from which the carbon layer has been removed. By reusing the first underlying substrate without losing it, the production cost of the polycrystalline silicon carbide substrate can be reduced.