| 摘要 |
PURPOSE:To reduce the occurrence of the defects in an active element region and to reduce the probability of attachment of dust extremely, by forming a gate oxide film at the earliest stage of the manufacturing processes. CONSTITUTION:A gate osioxide film 12 is formed. Then a gate electrode 16 and an arsenic ion implanted layer 18, which is to become source and drain regions, are formed. Thereafter selective oxidation is performed. Thus a part of a polycrystalline film, which is deposited when the gate oxide film 16 is formed, is converted into a thermal oxide film 21. Element isolation is provided in this way. This method is different from the conventional method, in which an active element is exposed and formed after many processes. Crystal detects do not occur in the active element region and attachment of dust can be avoided. Therefore the troubles due to these causes can be reduced extremely. |
