| 摘要 |
An impurity buried layer constructed by two buried regions formed by impurities of identical type exist, a buried region formed by an impurity having a slow diffusion speed is provided on the entire surface of a transistor formation region, and a buried region formed by an impurity having a fast diffusion speed is provided inwardly from beneath the inside end of an isolation insulating film serving as a region on which an electric field concentrates partially. |
