| 摘要 |
PURPOSE:To readily control the thickness of an active region by forming the region by accumulating or epitaxially growing. CONSTITUTION:A thermal oxide film 14 and a p<+> type region 15 are formed on the surface of a p type semiconductor substrate 11. Polysilicon is accumulated, n type impurity ions are implanted or diffused to form an n<+> type polysilicon layer 16, heat treated to single crystallize the surface. An n type epitaxially grown layer 17 is formed, a portion to become a separate region is etched to form a recess 20. An oxide film 21 is coated on the inner wall of the recess 20, buried with an insulator 22 such as polysilicon, and the entire surface is coated with an oxide film 23. A p type base layer 24, an n<+> type emitter layer 25 and an n<+> type collector contact layer 26 are formed, and electrodes 27 are formed to produce a transistor. |
