Patent ID: 8198182

Claim:
An annealing method for annealing a device including a silicon carbide substrate, the method comprising steps of: forming an impurity doped region in the silicon carbide substrate by ion-implantation of the impurity into the silicon carbide substrate; and annealing the impurity doped region in the silicon carbide substrate in an atmosphere in which a partial pressure of residual H 2 O in a heat treatment chamber is not greater than 10 −2 Pa by evacuating the heat treatment chamber so that a pressure in the heat treatment chamber is not greater than 10 −5 Pa, wherein, during the annealing step, the silicon carbide substrate implanted with the impurity is covered by a cap having a through-hole, wherein the through-hole is an air vent communicating between a space in the heat treatment chamber and a space formed between the cap and the heat treatment chamber, and wherein the through-hole is formed in the cap.