SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To reduce reverse leakage current of a semiconductor device produced by grinding a semiconductor substrate to have a smaller thickness and performing ion implantation on the grinding surface. SOLUTION: A diode 100 includes a P-anode layer 2 and an anode electrode 5, which are formed on the front side of an N-drift layer 1 and an N+cathode layer 3 and a cathode electrode 6 which are formed on the back side of the N-drift layer 1, wherein an N cathode buffer layer 4, having a higher density than the N-drift layer 1 and a lower density than the N+cathode layer 3, is formed between the N-drift layer 1 and the N+cathode layer 3, so that the N cathode buffer layer 4 has a larger thickness than that of the N+cathode layer 3. Thus, when a breakdown voltage is applied as a reverse-bias voltage, a depletion layer is stopped in the N cathode buffer layer 4 and is prevented from reaching the N+cathode layer 3, thereby suppressing leakage current. COPYRIGHT: (C)2007,JPO&INPIT