ALGAAS GAAS CHARGE INJECTION TRANSISTOR NEGATIVE-RESISTANCE FIELD-EFFECT TRANSISTOR FABRICATED WITH SHALLOW PD GE OHMIC CONTACTS/

AlGaAs/GaAs charge injection transistor (CHINT)/negative resistance fi eld-effect transistor (NERFET) devices are fabricated with Pd/Ge ohmic contacts. Pd and Ge are deposited by e-beam evaporation. The contact metal layers are annealed by rapid thermal annealing at 450-500-degree s-C for 1 min. This gives a shallow ohmic contact and low specific con tact resistivity. The better rho(c) are on the order of 10(-6) OMEGA C M2 . Using Pd/Ge contacts and rapid thermal annealing method, the meta llization of CHINT/NERFET becomes much less critical. Good device perf ormance under NERFET mode and CHINT mode is achieved. The largest peak -to-valley ratio of NERFET is about 15 at room temperature. The proces s developed in this work considerably simplifies the fabrication of CH INT/NERFET devices.