Patent ID: 8168486

Claim:
A method of manufacturing an enhancement mode (e-mode) high electron mobility transistor (HEMT), comprising: forming a first compound semiconductor layer over a surface of a substrate; forming a second compound semiconductor layer over a surface of the first compound semiconductor layer opposite the substrate surface; forming a first dielectric over a surface of the second compound semiconductor layer opposite the surface of the first compound semiconductor; defining a source contact area, a drain contact area, and a gate contact area, through the first dielectric using one mask layer to expose portions of the second compound semiconductor layer; forming a second dielectric conformally over the first dielectric and the exposed portions of the second compound semiconductor layer; etching the second dielectric to expose the gate area; isotropically etching the first dielectric exposed in the gate contact area to form an etched area; growing epitaxial p-type second compound semiconductor on the exposed gate contact area to substantially fill the etched gate contact area and to cover at least a portion of the etched area of the first dielectric.