Digital Circuits in a Multi-Functional SAGFET MMIC Technology

In this paper a possible implementation of digital circuits in a MMIC SAGFET/SAGHEMT technology is described. This technology has been developed at the Alenia Marconi Systems (AMS) and it is well suited for the integration of digital and microwave parts in the same GaAs substrate. A test circuit with FET’s for DC/AC characterization, inverter chains, ring oscillators and frequency dividers has been designed and is now under fabrication at AMS. Since now only Depletion MESFET transistors were available. However, the technology is still growing and in the near future Enhancement and Depletion MESFET and HEMT transistors will allow the implementation of E/D logic circuits