The performance of GaAs logic gates in LSI

Abstract

This paper examines the theoretical performance of GaAs MESFET logic gates and attempts to obtain a realistic comparison of GaAs vs Si devices under typical loading conditions imposed by large random logic arrays. GaAs was found to have a speed advantage of 3-6 over Si, depending on the operating voltage. Normally off type MESFET devices were attractive at gate lengths of 0.5µm, giving loaded delays of 105ps. Logic swings were 600mV requiring a threshold voltage control of ±50mV.