Patent ID: 9111904
Filing Date: 2015-08-18
Classification: H01L

Abstract:
1. A method comprising: providing a silicon substrate; epitaxially growing a gallium nitride (GaN) layer over the silicon substrate; epitaxially growing a donor-supply layer over the GaN layer; forming a gate on the donor-supply layer; depositing a passivation film over the gate and the donor-supply layer; etching a portion of the passivation film to form a source opening and a drain opening exposing a portion of the donor-supply layer, wherein the source opening and the drain opening are disposed on opposite sides of the gate, wherein a top surface of the passivation film over at least a portion of the gate is not flat; depositing ohmic metal layers over the source opening, the drain opening and the passivation film; and etching a portion of the ohmic metal layers to form a source structure and a drain structure, wherein the source structure comprises a source overhead portion disposed over at least a portion of the passivation film between the source structure and the gate.