| 摘要 |
PURPOSE:To easily form both a mask arranging step and a channel stopper on the surface of a semiconductor substrate under self-arrangement, by utilizing the difference in impurity concentration. CONSTITUTION:An n<+>-layer 2 is provided on a p-type silicon substrate 1. When the layer 2 is oxidized at a low temperature under steam, oxide films 3, 4 are produced thick on the n<+>-layer 2 and thin on the p-type substrate 1, respectively. Boron ions are implanted through the thin film 4 to selectively make a thin p-layer 5 under self-arrangement. When a separating oxide film is produced in an epitaxial layer 6 on the p-layer 5, the layer 5 effectively acts as a channel stopper. A mask arranging step 7 is made on the epitaxial layer on the n<+>-layer 2 under self-arrangement. |
