Direct-coupled GaAs ring oscillators with self-aligned gates

The performance of direct-coupled GaAs MESFET ring oscillators having a 1µm self-aligned recessed-gate structure defined by optical contact lithography on CVD epitaxial material is reported. Propagation delays as low as 20.9 and 16.1 ps/stage have been achieved at 300 and 77 K, respectively, representing the fastest results reported to date for GaAs ring oscillators having conventional 1-µm gate technology.