InGaP/InGaAs Doped-Channel Direct-Coupled Field-Effect Transistors Logic with Low Supply Voltage

InGaP/InGaAs doped-channel direct-coupled field-effect transistor logic (DCFL) with relatively low supple voltage is demonstrated by two-dimensional analysis. In the integrated enhancement/depletion-mode transistors, subband and two-dimensional electron gas (2DEG) are formed in the InGaAs strain channels, which substantially increase the channel concentration and decrease the drain-to-source saturation voltage. The integrated devices show high turn-on voltage, high transconductance, broad gate voltage swing, and excellent high frequency performance, simultaneously. Furthermore, the integrated devices exhibit large noise margins for DCFL application with low supply voltage of 1.5 V attributed from the relatively small saturation voltages of the studied integrated devices.