| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an insulation gate type semiconductor element having a trench structure capable of maintaining a dielectric breakdown voltage high even using a silicon carbide substrate preferable for obtaining a good semiconductor element characteristic. <P>SOLUTION: A method includes a step for etching a surface of a silicon carbide substrate to form a recess on the surface; a step for radiating particle beams from above the surface to form a damaged layer at least on a bottom face of the recess and the surface of the substrate near the recess; and a step for heat treating the silicon carbide substrate in an oxidative atmosphere to form an oxide film which is thin on a side of the recess and thick on the bottom face and on the surface of the substrate near the recess, at least on the side face of the recess and the bottom face, on which the damaged layer is formed, and on the surface of the substrate near the recess. <P>COPYRIGHT: (C)2012,JPO&INPIT |
