Advantages of metallic-amorphous-Silicon-gate FET´s in GaAs LSI applications

A Schottky barrier as high as 1 V is obtained for contact between a ternary amorphous film, a-Si-Ge-B, and an n-type GaAs crystal. A metallic-amorphous-silicon-gate FET (MASFET) was made using the amorphous film as a gate contact. GaAs MASFET characteristics are superior to GaAs MESFET characteristics in application to LSI\´s with a DCFL configuration because the DCFL circuits with the GaAs MASFET\´s provide a logic level as high as 0.94 V and widen the circuit operation margin. Full operation is obtained from a 1 Kword × 2 bit SRAM with GaAs MASFET\´s, which is considered to be mainly due to the wide operation margin. The measured propagation delay time of the DCFL inverter is 34 ps at supply voltage V and power consumption of 1.9 mW/gate.