Patent ID: 7663187

Claim:
A semiconductor device comprising: a gate formed over a semiconductor region; a first impurity-diffused region formed, as being aligned with said gate, in a surficial layer of said semiconductor region and having a first depth; a second impurity-diffused region formed, as being distant from said gate with a first distance and having a second depth; and a third impurity-diffused region formed, as being distant from said gate with a second distance and having a third depth; wherein the third depth is larger than the first depth, and the second depth is larger than the third depth, wherein the first distance is longer than the second distance, wherein said third impurity-diffused region is formed containing at least any one diffusion suppressive element selected from germanium, nitrogen, fluorine and carbon for the case where the impurity contained in the first and the third impurity-diffused regions is an n-type impurity said third impurity-diffused region does not include n-type impurity but includes only said diffusional constraint element.