Patent ID: 8269256
Filing Date: 2012-09-18
Classification: H01L

Abstract:
1. A semiconductor device comprising: a semiconductor substrate; a gate insulating film formed over the semiconductor substrate; a gate electrode formed on the gate insulating film; a first semiconductor layer which is embedded into a portion on both sides of the gate electrode in the semiconductor substrate, and which comprises Si and a 4B group element other than Si; a second semiconductor layer which is embedded into the portion on both sides of the gate electrode in the semiconductor substrate, so as to be superposed on the first semiconductor layer, and which comprises Si and a 4B group element other than Si; a first side wall formed on the side of the gate electrode in contact with the semiconductor substrate and which comprises a tensile insulating film; and an intermediate layer between the first semiconductor layer and the second semiconductor layer, the propagation of dislocation from the second layer to the first layer being blocked by the intermediate layer, wherein the gate electrode is more separated from an end of the first semiconductor layer than from an end of the second semiconductor layer, and wherein the second semiconductor layer is formed in contact with the side surface of the first side wall.