INVESTIGATION OF INGAAS BASED PSEUDOMORPHIC STEP-DOPED-CHANNEL FIELD-EFFECT TRANSISTOR (SDCFET)

A heterostructure field-effect transistor (HFET) with a pseudomorphic step-doped-channel (SDC) profile has been fabricated and investigated. The studied SDCFET provides the advantages of high current density, h igh breakdown voltage, large gate voltage swing for high transconducta nce operation, and the adjustable threshold voltage. In this paper, a theoretical model is built to analyze the DC performance. For a practi cal device of 1 x 100 mu m(2) gated dimension, a maximum drain saturat ion current of 735 mAmm(-1), a maximum transconductance of 200 mSmm(-1 ), a gate breakdown voltage of 15 V, a wide gate voltage swing of 3.3 V with transconductance (g(m)) higher than 150 mSmm(-1) and a threshol d voltage of -3.7 V are obtained, respectively. The theoretical data a re consistent with experimental results. These good performances show the studied SDCFET have promise for high-speed, high-power circuit app lications. (C) 1997 Elsevier Science Ltd.