Patent ID: 8823061

Claim:
A semiconductor device, comprising: a first semiconductor layer; a second semiconductor layer provided on the first semiconductor layer with a heterojunction interface interposed therebetween; a two-dimensional carrier gas layer provided near the heterojunction interface in the first semiconductor layer; a source electrode electrically connected to one end of the two-dimensional carrier gas layer; a drain electrode electrically connected to the other end of the two-dimensional carrier gas layer; a gate electrode provided above the two-dimensional carrier gas layer between the source electrode and the drain electrode; and an auxiliary electrode provided above the two-dimensional carrier gas layer between the gate electrode and the drain electrode; and a first recess in the semiconductor layer spanning from the surface of the second semiconductor layer toward the heterojunction interface between the gate electrode and the auxiliary electrode forming a channel resistance of the two-dimensional carrier gas layer between the gate electrode and the auxiliary electrode that is higher relative to a channel resistance of the two-dimensional carrier gas layer between the gate electrode and the source electrode.