Patent ID: 7323728

Claim:
A semiconductor device, comprising: a semiconductor substrate; an n + -type semiconductor layer formed on the 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 having a material having a first band gap; a second n-type semiconductor layer formed on the p-type semiconductor layer, the second n-type semiconductor layer being smaller than the p-type semiconductor layer in area and having a material having a second band gap larger than the first band gap; an implant portion formed to penetrate, from a region of the p-type semiconductor layer where the second n-type semiconductor layer is not formed, the first n-type semiconductor layer and the n + -type semiconductor layer to reach the semiconductor substrate, the implant portion dividing the p-type semiconductor layer, the first n-type semiconductor layer, and the n + -type semiconductor layer into two regions, one region of the two regions being an active region on which the second n-type semiconductor layer exists, another region of the two regions being a non-active region on which the second n-type semiconductor layer does not exist, the active region configured to accept an RF signal, the non-active region configured to accept a DC voltage; and an electrode formed on a region of the p-type semiconductor layer where the second n-type semiconductor layer is not formed, so as to bridge over at least the implant portion and to be in contact with both of the p-type semiconductor layer of the active region and the p-type semiconductor layer of the non-active region.