Patent ID: 8669561
Filing Date: 2014-03-11
Classification: H01L

Abstract:
1. A semiconductor device comprising: a semiconductor substrate made of silicon carbide in which an angle between a normal vector of a substrate surface and an orientation <0001> or <000-1> is 0° or more and 8° or less; a first conductivity type semiconductor layer made of silicon carbide formed on the semiconductor substrate; an active area formed on a surface of the semiconductor layer; a first semiconductor area of a second conductivity type having an impurity concentration and depth, formed on the surface of the semiconductor layer to surround the active area; a second semiconductor area, provided to adjoin an outer side of the first semiconductor area on the surface of the semiconductor layer and surround the first semiconductor area, in which a second conductivity type impurity area having the same impurity concentration and the same depth as those of the first semiconductor area is formed in a mesh shape; a third semiconductor area of the second conductivity type formed around the first semiconductor area and the second semiconductor area and having a depth and impurity concentration; a first electrode provided on the active area; and a second electrode provided on a rear surface of the semiconductor substrate, wherein, where γdenotes a relative permittivity of silicon carbide, Ec a depthwise integral value of the impurity concentration of the third semiconductor area is 0.4 γEc