One watt, very high efficiency 10 and 18 GHz pseudomorphic HEMTs fabricated by dry first recess etching

The authors report 10- and 18-GHz power performance of double recessed 1.2-mm periphery pseudomorphic high electron mobility transistors (PsHEMTs). They have obtained demonstrably better uniformity in performance than conventionally fabricated PsHEMTs. This was accomplished by incorporating a new approach to recess formation using selective reactive ion etching of the first recess in a double recessed structure. The critical first recess was formed with exceptional uniformity using dry etching and an AlGaAs etch stop layer. Simultaneous power, gain, and power-added efficiency, representative of many devices, are summarized.<>