Patent ID: 6639273
Filing Date: 2003-10-28
Classification: H01L

Abstract:
A silicon carbide n channel MOS semiconductor device, comprising:a semiconductor substrate comprising silicon carbide, said substrate including a p base region, an n+ source region and an n+ drain region; a gate insulating film formed on a surface of the p base region; a gate electrode provided on the gate insulating film; and first and second main electrodes that allow current to flow therebetween; wherein current flowing between the first and second main electrodes is controlled by controlling an electron concentration of an inversion layer that is induced in a surface layer of the p base region located under the gate insulating film when a positive voltage is applied to the gate electrode; wherein an effective acceptor concentration measured in the vicinity of an interface between the p base region and the gate insulating film is in a range of 1Ã—1013 to 1Ã—1016 cmâˆ’3; and wherein an impurity concentration in the surface layer of the p base region is relatively lower than an impurity concentration of the p base region.