| 摘要 |
PURPOSE:To form an element isolation film in an ideal form without bird's beaks and bird's heads by burying an insulation film into a recess formed on a substrate. CONSTITUTION:An etching mask (e.g. Al film) 22 is formed on a Si substrate 21, which is patterned with a resist film 23 as the mask, thereafter etching is performed, and thus the recess 25 is formed at the region of element isolation of the substrate. Next, after the impurity 26 for inversion prevention is implanted, and then the resist film 23 is removed, the Si oxide film 27 is formed over the surface of the substrate 21 including the recess 25. Then the edge parts of the recess 25 are removed until the end parts of the etching mask 22 expose by performing inisotropic etching over the entire surface of the Si oxide film 27, and accordingly inclined surfaces 28 are formed. The etching mask 22 is etched together with the oxide film 27 thereon by lift-off. Thereafter, the impurity 26 is activated by performing heat treatment, the shape of the oxide film 27 is smoothed. |
