Patent ID: 7244973
Filing Date: 2007-07-17
Classification: H01L

Abstract:
1. A field-effect semiconductor device comprising: a semiconductor layer comprising semiconductor represented by the formula Al a gate electrode formed on the semiconductor layer; and a source electrode and a drain electrode formed by self-alignment using the gate electrode as a mask, wherein the semiconductor layer comprises a spacer layer, a Si-containing carrier-supplying layer, and a cap layer; the spacer layer, the Si-containing carrier-supplying layer, and the cap layer comprising the gallium nitride-based compound semiconductor represented by the formula Al wherein the field-effect semiconductor device further comprises a GaN-based channel layer, and the spacer layer, the Si-containing carrier-supplying layer, and the cap layer are deposited in that order on the GaN-based channel layer, wherein the gate electrode, the source electrode, and the drain electrode are formed on the cap layer, and wherein the gate electrode has a multi-layered structure including a layer comprising a high-melting point metal selected from the group consisting of Mo, Pt, W, Hf, and Cr, the high-melting point metal being sandwiched between a layer comprising Au and a layer comprising Ni.