High performance complementary logic based on GaAs/InGaAs/AlGaAs HIGFETs

Results for planar, self-aligned gate, complementary, pseudomorphic GaAs-InGaAs-AlGaAs HIGFET devices are presented. The gate leakage is found to be controllable by increasing the AlAs molar fraction in the barrier layer. A planar n-doped layer beneath the InGaAs channel is shown to shift the threshold voltages of the devices and to reduce considerably the output conductance of the p-channel FET. The operation of complementary inverters depends sensitively on the relative values of supply voltage and gate turn-on voltages. Large inverter noise margins are demonstrated, and the power and speed of complementary ring oscillators are discussed.<
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