| 摘要 |
PURPOSE:To prevent the breakdown of a gate insulating film due to ion implantation by forming source and drain regions under the state the uppermost layer on a semiconductor substrate is covered by a conductive film by ion implantation method. CONSTITUTION:A poly crystal Si film 3 is deposited on the entire surface of the Si substrate 1, and conductive impurities are doped. Then a gate electrode is formed. In this case, a thin layer of the poly crystal Si is left at the part other than the gate electrode, by stopping the etching before the final point is reached. Then an ion beam 4 is irradiated, and a source and drain diffused layer 5 is formed. In this injection, the thin surface layer 3 and a conductive wafer supporting substrate 8 are shorted. In this method, the breakdown of the gate insulating film does not occur, and the ion implantation to the source and drain layer can be performed. |
