Patent ID: 8709950

Claim:
A manufacturing method of a silicon carbide substrate comprising the steps of: preparing a base substrate having a main surface and made of silicon carbide; washing said main surface using a first alkaline solution; washing said main surface using a second alkaline solution after the step of washing using said first alkaline solution, the main surface of the base substrate is etched after washing the main surface using the second alkaline solution; an average of residues on the main surface being etched are between 0.2 and 5 in number, and the residues include at least one of an abrasive liquid and a fixing agent for fixing the silicon carbide substrate during polishing, the residues are measured by obtaining an average of values determined from five-point measurement within a visual field with sides of 50 μm, and when a visual field with sides other than 50 μm is used, the obtained values are converted into those corresponding to the sides of 50 μm.