| 摘要 |
PURPOSE:To enhance withstanding voltage for electrostatic breakdown and to reduce processes, in a IC comprising MISFETs, by constituting the peripheral part by the MISFET having a single drain structure, constituting the inner IC by the MISFET having a double-drain structure, and sharing a part of the manufacturing processes. CONSTITUTION:An n<-> type well region 2 is formed in a p<-> type Si substrate 1. Thick field insulating films 3 are provided on a P type channel stopper region 4. A thin insulating film 5 is deposited on the exposed part of the region 4. A gate electrode 6C is formed at the center of the surface. Thus a single-drain structured MISFET is obtained. The surface is covered by a mask 13. A double- drain structured MISFET is provided at the neighboring position. At this time one insulating film 3 is shared. A gate electrode 6B is formed between and said insulating film 3 the other facing insulating film 5. Thereafter, the source and drain regions of an n<-> type layer 7B are formed on both sides of the electrode 6B on n<+> type layer 8B. On the well region 2, p<+> type source and drain regions 9C are formed. |
