| 摘要 |
PROBLEM TO BE SOLVED: To soften the current waveform of a high-speed diode at the time of reverse recovery operation.SOLUTION: In a diode having a PiN-type diode structure which flows current in a longitudinal direction, a carrier residual layer (N+ layer) which generates carriers when reverse bias is applied is locally disposed in a region of a drift layer outside a depletion region formed when reverse bias is applied. Carriers (electrons) are supplied by the carrier residual layer at the time of switching operation, thereby causing current to flow. Therefore, rapid carriers do not disappear and the current waveform at the time of reverse recovery operation can be softened. Due to a structure in which a thick carrier residual layer (N+ layer) is not provided on a rear surface of the diode, the current waveform can be softened without increasing Vf. |
