Patent ID: 7888712
Filing Date: 2011-02-15
Classification: H01L

Abstract:
1. A semiconductor device, comprising: a first conductive type SiC semiconductor substrate; a second conductive type well formed on the SiC semiconductor substrate, the second conductive type being different from the first conductive type; a first impurity diffusion layer formed by introducing a first impurity of the first conductive type in a first region surrounding the well in the SiC semiconductor substrate and partially overlapping the well; a second impurity diffusion layer formed by introducing a second impurity of the first conductive type in a second region in the well, the second impurity diffusion layer being spaced apart by a predetermined distance from the first impurity diffusion layer; a gate electrode opposed to a channel region between the first impurity diffusion layer and the second impurity diffusion layer with a gate insulating film sandwiched between the gate electrode and the first and second impurity diffusion layers; and a source diffusion region of the first conductive type, the source diffusion region being formed in a third region in the well so as to be overlapped at least partially with the second impurity diffusion layer, wherein the first and second impurity diffusion layers have respective outer peripheries, the first impurity diffusion layer has an inner periphery, and the channel region is disposed between the outer periphery of the second impurity diffusion layer and the inner periphery of the first impurity diffusion layer, and wherein the source impurity region has an outer periphery, the outer periphery of the second impurity diffusion layer being closer than the outer periphery of the source impurity region to the first impurity diffusion layer, and wherein the concentration of the source diffusion region is higher than that of the second conductive type well.