Patent ID: 7915617
Filing Date: 2011-03-29
Classification: H01L

Abstract:
1. A semiconductor device comprising: a first semiconductor layer of silicon carbide of a first conductivity type; a second semiconductor layer of silicon carbide of a second conductivity type selectively provided on the first semiconductor layer; a main electrode layer of silicon carbide of the first conductivity type selectively provided on the second semiconductor layer; a gate insulating film provided on the second semiconductor layer; a gate electrode formed on the gate insulating film; and a third semiconductor layer of the first conductivity type intervening a current path which is formed between the main electrode layer and the first semiconductor layer when an ON voltage is applied to the gate electrode, the third semiconductor layer being selectively provided on the first semiconductor layer and being adjacent to the second semiconductor layer, the current path includes a part of the second semiconductor layer, the part being provided between the main electrode layer and the third semiconductor layer, and the part being covered by the gate insulating film, and a doping density of the third semiconductor layer being higher than a doping density of the first semiconductor layer; and further comprising an accumulation channel layer of silicon carbide of the first conductivity type selectively provided between the gate insulating film and the second semiconductor layer and having a lower impurity concentration than the main electrode layer, and the current path includes the accumulation channel layer and an inversion channel layer, the accumulation channel layer and the inversion channel layer being connected in series, and the inversion channel layer being formed in a semiconductor of the second conductivity type when the ON voltage is applied to the gate electrode.