| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device which can control trade-off characteristics between ON-state voltage and a recovery loss without lifetime control by controlling the ON-state voltage by an impurity concentration of a P type anode layer without depending on the impurity concentration of the P type anode layer while maintaining withstand voltage, and which can inhibit a snap-off phenomenon.SOLUTION: A semiconductor device comprises: a P type anode layer 2 formed on an Ntype drift layer 1; a trench 3 provided so as to pierce the P type anode layer; a conductive material 5 is filled in the trench 3 via an insulation film 4; and an N type buffer layer 6 provided between the Ntype drift layer 1 and the P type anode layer 2. The N type buffer layer 6 has an impurity concentration higher than that of the Ntype drift layer 1. The P type anode layer 2 has a plurality of P type layers arranged along a longer direction of the trench 3 in planar view like stepping stones. |
