Microwave Frequency Digital Circuits Using GaAs Mesfet´s with a Planar Self-Aligned Technology

This paper describes some circuits realised with the first generation of GaAs integrated logic circuits family. Intended for maximum speed, this family is based upon normally on field effect transistors and Schottky diodes. The use of a fully planar selfaligned technology allowed us to reach 75 ps propagation delays and binary frequency division above 3.3 GHz with 3 um minimum details on the masks. This self-alignment feature, together with a tight control of electrical parameters, resulted in a very good yield for SSI circuits.