Patent attributes
A method of fabricating a III-N device includes forming a III-N channel layer on a substrate, a III-N barrier layer on the channel layer, an insulator layer on the barrier layer, and a trench in a first portion of the device. Forming the trench comprises removing the insulator layer and a part of the barrier layer in the first portion of the device, such that a remaining portion of the barrier layer in the first portion of the device has a thickness away from a top surface of the channel layer, the thickness being within a predetermined thickness range, annealing the III-N device in a gas ambient including oxygen at an elevated temperature to oxidize the remaining portion of the barrier layer in the first portion of the device, and removing the oxidized remaining portion of the barrier layer in the first portion of the device.
