| 摘要 |
<p>A semiconductor device formed in a semiconductor substrate and having a gate electrode formed on said semiconductor substrate, source and drain regions formed in said semiconductor substrate wherein source and drain regions comprise: a first impurity region doped with impurities of opposite conductivity type to that of the semiconductor substrate formed at portions of adjacent to the edge of the gate electrode; a second impurity region doped with impurities of opposite conductivity type to the semiconductor substrate formed at portions under the first impurity region, the impurities of the second impurity region having a diffusion coefficient larger than that of the impurities of the first impurity region; a third impurity region doped with impurities of opposite conductivity type to the semiconductor substrate formed-at portions spaced apart from the edge of the gate electrode the third impurity region having a higher concentration than that of the first and the second impurity region and the impurities of the third impurity region having a diffusion coefficient smaller than that of the second impurity region.</p> |
