CIRCUIT PERFORMANCE OF COMPLEMENTARY HETEROSTRUCTURE MISFET INVERTER USING HIGH MOBILITY 2DEG AND 2DHG.

A complementary circuit using high-mobility two-dimensional electron and hole gases (2DEG and 2DHG) induced at the AlGaAs/GaAs heterointerface has been successfully fabricated on an n** plus -Ge/undoped AlGaAs/undoped GaAs heterostructure. Transfer characteristics of a two-stage inverter show sufficiently high and low output levels. A 15-stage ring oscillator shows a minimum delay time of 94 ps at 300 K and 64 ps at 77 K. Circuit simulation using a new gate current model shows that for a multi-input logic gate, a NAND gate configuration is superior to a NOR gate configuration, and that high-speed operation below 20 ps at 77 K is made possible by reducing the gate length to 0. 5 mu m.