| 摘要 |
PROBLEM TO BE SOLVED: A first diode, consisting of a p-n junction and a second diode consisting of a Schottky junction are provided side by side and the surface concentration of the layer constituting the p-n junction is specified so as to suppress a pop-up voltage. SOLUTION: In an active part, a first diode consisting of an n<+> -layer 13, an n-layer 14, a p-layer 15 and a second diode consisting of an n<+> -layer 13, an n<-> -layer 14, a p-layer 16 and a Schottky barrier side by side are provided between a pair of main surfaces. By setting the concentration of the p-layer in the range of 1×10<15> cm<-3> to 1×10<17> cm<-3> , an implantation from the p<+> -layer 15 to the n<-> -layer 14 is suppressed, so as to reduce the carrier near a p-n junction, thus enabling suppression of Irp(inversed recovery current peak value). The carrier to be stored in the n-layer due to carrier implantation from an n<+> /n junction does not drop, inspite of the lowered concentration of the p-layer 16, and also the life time of the n<-> -layer 14 is the same so that an inverse recovery time Trr until the inversed recovery current becomes zero hoes not change, thus reducing a current change rate dir /dtrr of the inversed recovery current so as to suppress a pop-up voltage. |
