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 WSix(≈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 gmof 170 mS/mm.