SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device making the inhibition of a thermal runaway and the further ensuring of frequency characteristics compatible. SOLUTION: The semiconductor device has an n+-type semiconductor layer formed on a semiconductor substrate, a first n-type semiconductor layer formed on the n+-type semiconductor layer, a p-type semiconductor layer formed on the first n-type semiconductor layer and made of a material having a first band gap, and a second n-type semiconductor layer formed on the p-type semiconductor layer and made of the material having a second band gap having an area smaller than the p-type semiconductor layer and larger than the first band gap. The semiconductor device further has an implanting section being formed while penetrating the first n-type semiconductor layer and the n+-type semiconductor layer from the p-type semiconductor layer in a region, in which the second n-type semiconductor layer is not formed, and reaching the semiconductor substrate and dividing the p-type semiconductor layer, the first n-type semiconductor layer and the n+-type semiconductor layer into two regions. The semiconductor device further has an electrode formed astride over at least the implanting section on the p-type semiconductor layer in the region in which the second n-type semiconductor layer is not formed. COPYRIGHT: (C)2006,JPO&NCIPI