Patent ID: 8722474

Claim:
A method of fabricating a semiconductor device, comprising: forming a cap layer on a semiconductor substrate having a structure including a plurality of epitaxial layers and etching a part of the cap layer, to form an active region; sequentially forming a first nitride layer, a second nitride layer and a resist pattern for forming a gate on the active region and the cap layer; sequentially etching the second nitride layer and the first nitride layer through the resist pattern and removing the resist pattern, to form a stepped gate insulating layer pattern; forming a gate head pattern on the second nitride layer; etching a part of a Schottky layer in an upper most part of the semiconductor substrate through the gate insulating layer pattern, to form an under-cut region; depositing a heat-resistant metal through the gate insulating layer pattern and the gate head pattern, to form a stepped gate electrode; and removing the gate head pattern and depositing an insulating layer.