| 摘要 |
PURPOSE:To improve the withstand characteristic by forming a P-N junction in a semiconductor substrate, the forming a mesa groove, and heat treating it, thereby moving the position of the P-N junction exposed with the inner wall of the groove from the original position. CONSTITUTION:When a heat treatment is performed in an oxidative atmosphere in the state that the exposed projection 6 of a P-N junction end and an oxide film 8 is formed on the inner wall of a mesa groove, the projection 6 can be alleviated, and the P-N junction can be simultaneously moved from the initial position 5 to the position 7. Thus, the decrease in the withstand voltage due to the increase in the electric field intensity owing to the exposed projection of the junction end can be eliminated to improve the withstand characteristic. |
