HIGH-PERFORMANCE DOUBLE-DOPED INALAS/INGAAS/INP HETEROJUNCTION FET WITH POTENTIAL FOR MILLIMETER-WAVE POWER APPLICATIONS

Lattice matched InAlAs/InGaAs/InP heterojunction field-effect transistors (HJFETs), which have carrier supplying layers on and beneath the undoped InGaAs channel layer, have been successfully fabricated. A selective recess of the InGaAs channel edge at a mesa sidewall together with the use of a wide recess gate structure leads to a 5.7 V gate-drain breakdown voltage without kink effects. The fabricated HJFET with a 0-15 x 100 mum2 T-shaped gate exhibits a 700 mA/mm maximum drain current, a voltage gain of 14, and a 345 GHz maximum frequency of oscillation.