| 摘要 |
PROBLEM TO BE SOLVED: To inhibit diffusion of elements contained in a source electrode and a drain electrode into a semiconductor layer.SOLUTION: A semiconductor device comprises: an operation layer 20 which is provided on a substrate 10 and composed of a GaAs-based semiconductor; a first AlGaAs layer 24, 26 provided above the operation layer; a gate electrode 34 provided on the first AlGaAs layer; an n-type second AlGaAs layer 28 which is selectively provided on the first AlGaAs layer in regions which sandwich a gate region and which has an Al composition ratio larger than that of the first AlGaAs layer and the Al composition ratio is not less than 0.3 and not more than 0.5; an n-type GaAs layer 30 selectively provided on the second AlGaAs layer; and an Au-containing source electrode 36 and an Au-containing drain electrode 38 which are provided on the n-type GaAs layer to sandwich the gate electrode. |
