A new self-aligned GaAs FET with a Mo/WSixT-gate

An n+-layer and ohmic electrode self-aligned (NOSA) GaAs FET is a new self-aligned GaAs FET in which n
⁺
-layers and ohmic contacts in the source and the drain regions are self-aligned to a T-shaped gate formed with Mo and WSi
x
(≈0.6) double layers. Using the NOSA FET structure, the device area can be easily reduced because no alignment margin is needed. The fabricated FET's exhibit a transconductance g
m
of 170 mS/mm.