Patent ID: 11869964
Assignee: WOLFSPEED, INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 16:
17. A method of forming a transistor device, comprising:
providing a semiconductor epitaxial layer structure including a channel layer and a barrier layer on the channel layer, wherein the barrier layer has a higher bandgap than the channel layer;
forming a modified access region at an upper surface of the barrier layer opposite the channel layer;
forming a source contact and a drain contact on the barrier layer; and
forming a gate contact between source contact and the drain contact, wherein the modified access region comprises a material having a lower surface barrier height than the barrier layer;
wherein forming the modified access region comprises:
forming a sacrificial dielectric layer on the barrier layer;
annealing the sacrificial dielectric layer and the barrier layer; and
removing the sacrificial dielectric layer.