| abstract |
In a back surface hole injection type diode, by more effectively securing the effect of hole injection from the back surface of a semiconductor substrate, the performance of a semiconductor device is improved. In the semiconductor device, in a diode formed of a P-N junction including an anode P-type layer formed in the main surface of a semiconductor substrate and a back surface N + -type layer formed in the back surface of the semiconductor substrate, a back surface P + -type layer is formed in the back surface, and a surface P + -type layer is formed in the main surface right above the back surface P + -type layer to thereby promote the effect of hole injection from the back surface. |