SEMICONDUCTOR DEVICE

摘要

To suppress spike voltage generated at turn-off operation, a semiconductor device according to the invention comprises a first region composed of a first conductor, a second region composed of a second conductor formed on top of the first region, a third region composed of the first conductor formed on top of the second region and a fourth region composed of the second conductor formed on top of the third region. The second region is comprised of a depletion-layer forming auxiliary layer having a short lifetime and formed in the vicinity of the third region, a tail-current suppression layer having a shorter lifetime than that of the depletion-layer forming auxiliary layer and formed in the vicinity of the first region and a depletion-layer forming suppression layer having a longer lifetime than that of the depletion-layer forming auxiliary layer and formed between the depletion-layer forming auxiliary layer and the tail-current suppression layer.