| 摘要 |
PURPOSE:To improve the breakdown strength of a breakdown voltage or the amount of a current by a method wherein a single crystal layer of the same conductivity type as that of a semiconductor substrate is formed on the one conductivity type semiconductor substrate containing a high-concentration impurity and a Schottky electrode of the same depth as that of a guard ring is formed in the guard ring formed in such a way as to encircle a prescribed region shallower than the thickness of the single crystal layer with a layer of a conductivity type inverse to that of the single crystal layer. CONSTITUTION:An epitaxial layer 2 is formed on a substrate 1 and thereafter, a P<+> layer is formed at a part including a region to be formed with a guard ring 3 and a Schottky electrode 5 in a depth shallower than the thickness of the layer 2. Then, the P<+> layer located at the center part of the P layer is etched leaving the outer periphery only, which is used as the ring 3, of the P<+> layer to make the n-type layer expose and the electrode 5 is formed in an etching pit including the upper part of the ring 3 in the same depth as that of the ring 3. Accordingly, the breakdown strength of a breakdown voltage can be improved without reducing the amount of current or the amount of the current can be improved keeping the breakdown voltage intact. |
