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Monolithic integration of planar Gunn devices on GaAs is a very promising method to realize microcircuits for the Gbit/s range. Semiinsulating GaAs is readily available as substrate material. In this paper estimates of characteristic parameters of these circuits, such as maximum pulse rate, power consumption, and package density, are presented. Three different methods of domain control are available: a) by separate Schottky barrier diode; b) by MESFET; or c) by Schottky barrier gate on the channel of the Gunn device. Theoretical limits for these methods are given. Maximum pulse rates of 11, 5, and 7 Gbit/s, respectively, can be expected. Unidirectionality and trigger drive of the three methods are rated. Experimental integrated circuits were built to demonstrate the capability of the methods of domain control. Comparison with calculations yields good agreement. Coming close to the theoretical limits has not yet been accomplished in all practical cases since further miniaturization of the circuits and improvement of the material properties relevant to domain processes is needed. After progress in these two points it is expected that the theoretical limits will be reached. |
