Patent ID: 10510543

Abstract:
A semiconductor device includes an n−-type drift layer of an formed on an n+-type SiC substrate; a p-type layer provided on a surface opposite that facing the n+-type SiC substrate; and an n-type buffer layer provided, as a recombination promoting layer, between the n−-type drift layer and the n+-type SiC substrate, the n-type buffer layer having an impurity concentration higher than that of the n−-type drift layer. In the buffer layer, as a recombination site, a defect energy-level is introduced at a high concentration of 1×1012/cm3 or higher. The buffer layer promotes internal electron-hole recombination and without applying high energy to BPDs at an interface of the buffer layer and the SiC substrate, may reduce the amount of recombination near the interface even at a current density equivalent to that of a conventional structure and thereby, prevents characteristics degradation at the time of operation.