Patent ID: 6864507
Filing Date: 2005-03-08
Classification: H01L

Abstract:
1. A semiconductor device comprising: a compound semiconductor layer formed on a substrate; two heavily doped regions, which are defined and spaced apart from each other in the compound semiconductor layer and contain an impurity of a first conductivity type; a first active region, which is sandwiched between the two heavily doped regions and contains the impurity of the first conductivity type at a concentration lower than in the impurity of the first conductivity type in the two heavily doped regions; a gate insulating film formed on the active region; and a gate electrode formed on the gate insulating film, wherein the first active region comprises a plurality of heavily doped layers containing the impurity of the first conductivity type, and a plurality of semiconductor layers each composed of a lightly doped layer containing the impurity of the first conductivity type at a concentration lower than in the heavily doped layers, or composed of an undoped layer containing no impurity, the plurality of heavily doped layers and the plurality of semiconductor layers are alternately stacked, and the plurality of heavily doped layers and the plurality of semiconductor layers are made of SiC.