STRAINED SILICON STRUCTURE

摘要

A strained silicon substrate structure includes a first transistor and a second transistor disposed on a substrate. The first transistor includes a first gate structure and two first source/drain regions disposed at two sides of the first gate structure. A first source/drain to gate distance is between each first source/drain region and the first gate structure. The second transistor includes a second gate structure and two source/drain doped regions disposed at two side of the second gate structure. A second source/drain to gate distance is between each second source/drain region and the second gate structure. The first source/drain to gate distance is smaller than the second source/drain to gate distance.