MSI high-speed low-power GaAs integrated circuits using Schottky diode FET logic

A new planar high-density (0.001 sq mm/gate) GaAs IC technology has been used for fabricating MSI digital circuits containing up to 75 gates/chip. These digital circuits have potential application for gigabit microwave data transmission and processor systems. The circuits consist of Schottky diode FET logic NOR gates, which have provided propagation delays in the 75-200-ps range with dynamic switching energies as low as 27 fJ/gate on ring oscillator structures. Power dissipation levels are compatible with future LSI/VLSI extensions. Operation of D flip-flops (DFF) as binary ripple dividers (+2 - +8) was achieved at 1.9-GHz clock rates, and an 8:1 full-data multiplexer and 1:8 data demultiplexer were demonstrated at 1.1-GHz clock rates. This corresponds to equivalent propagation delays in the 100-175-ps range for these MSI circuits. Finally, a 3 x 3 parallel multiplier containing 75 gates functioned with a propagation delay of 172 ps/gate and with average gate power dissipations of as low as 0.42 mW/gate.