Semiconductor device

Abstract

The present invention provides a semiconductor device wherein the turning-off time thereof can be reduced substantially and, at the same time, the turned-on resistance thereof can also be prevented effectively from increasing as well. Lattice defects are distributed at a high concentration in a defect region an area in close proximity to the boundary surface between an n drift region and a p+ substrate. The half-value width of the distribution is set at a value which is large enough for the defect region to include a non-depletion region in the n drift region. However, the defect region is not spread to cover a diffusion layer. In this way, the turning-off time of the semiconductor device can be reduced considerably without being accompanied by an increase in turned-on resistance thereof. In addition, by employing an absorber with an uneven surface, the distribution of lattice defects can be obtained by carrying out radiation of ions at only one time.

Dependencies are inferred from the claim text.