Patent ID: 8039901

Claim:
A semiconductor device comprising: a semiconductor substrate; first and second adjacent transistors carried on the semiconductor substrate; a gate electrode carried on the semiconductor substrate, and source/drain regions located at each side of the gate electrode, the source/drain regions having implanted impurities, wherein, the source/drain regions further comprise (1) an epitaxial layer formed by epitaxially growing in a recessed position at a side of the gate electrode a semiconductor material having a different lattice constant from that of the semiconductor substrate, and (2) a diffusion layer disposed in a surface layer of the semiconductor substrate, the epitaxial layer has portions located at both sides of the gate electrode, and the epitaxial layer portions have the same width in a channel length direction, the diffusion layer is located between the source/drain epitaxial layer portions and the transistors, and a surface of the diffusion layer is lower than a surface of the semiconductor substrate beneath the gate electrode.