High-linearity and variable gate-voltage swing dual-gate In/sub 0.5/Ga/sub 0.5/P/In/sub 0.2/Ga/sub 0.8/As pseudomorphic high electron mobility transistors

InGaP/InGaAs pseudomorphic high electron mobility transistors (PHEMTs) fabricated using single-gate and dual-gate methodologies have been characterized with special emphasis to precisely control the device linearity and the gate-voltage swing. The key features of the proposed PHEMT profile are characterized in a composite channel by using a GaAs delta sheet and an undoped InGaAs layer. The gate voltage dependence of transconductance for the first equivalent gate with several V/sub gs2/ shows that the gate voltage swing available is in the range of 0 to 4.5 V.