GaAs IGFET digital integrated circuits

A technique to utilize GaAs insulated gate field effect transistors (IGFEI's) with large surface state densities in digital integrated circuits is described. In this technique, the threshold voltage is electrically set to obtain enhancement-mode characteristics of the IGFET's. Due to change in surface charge with time, these circuits will not function at very low frequencies. Several advantages of this IGFET technology over other enhancement-mode GaAs technologies are presented.