| abstract |
The present invention provides a semiconductor device and a method for manufacturing the semiconductor device in which a front surface element structure of an RC-IGBT having an FS structure is formed on the front surface of an n - type semiconductor substrate serving as an n - type drift layer (1). Next, a p + -type collector region ( 10 ), an n + -type cathode region ( 11 ) and an n + -type FS layer ( 12 ) are formed on the back surface of the n − -type semiconductor substrate. The n + type FS layer ( 12 ) is formed using selenium. Next, light ions are irradiated from the back surface of the n − type semiconductor substrate, and a first low lifetime region ( 31 ) is formed inside the n − type drift layer ( 1 ). Next, light ions are irradiated from the back surface of the n − type semiconductor substrate, and a second low lifetime region ( 32 ) is formed inside the n + type FS layer ( 12 ). Next, the defect density of crystal defects in the n + -type FS layer ( 12 ) is reduced by annealing. Thereby, the increase in leakage current can be suppressed, the electrical loss can be reduced, and the yield can be improved. |