Patent ID: 9666707
Date: 2017-05-30
CPC Classifications: H01L

Claim:
1. A high electron mobility transistor (HEMT), comprising: a barrier layer; a cap layer on the barrier layer; a gate recess in the cap layer that extends to, but not through, the barrier layer; a gate contact in the gate recess, wherein a sheet resistance of the barrier layer proximate the gate recess is substantially the same after an anneal of the barrier layer, the cap layer and the gate recess as an as grown sheet resistance of the barrier layer; and an encapsulation layer in the gate recess conformally on sidewalls of the gate recess and not on an upper surface of the cap layer, a top surface of the encapsulation layer being co-planar with a top surface of the cap layer, the encapsulation layer extending between the gate contact and the cap layer such that the gate contact is spaced apart from a surface of the barrier layer opposite an upper surface of the gate contact and the gate contact is directly on an entire surface of the encapsulation layer in the gate recess.