Recent Advances in Solid State Microwave Devices

In this paper recent advances in three areas of microwave solid state devices will be discussed, namely GaAs FETs, InP TEDs and Si TRAPATTs. A common factor in advancing the performance capability and yields of these devices has been improvements in materials technology. GaAs FET noise figures below 1.5 dB are now achievable in X band and power levels approaching 1 watt have been obtained from multicell devices in the same frequency range. Efficiency improvements in transferred electron oscillators have resulted from an understanding of the role of the cathode contact and the reproducible fabrication of two-zone cathode structures in InP. Extension of Si TRAPATTS technology into X band has led to the development of high efficiency, high power devices well-suited to pulsed oscillator and amplifier applications. Developments in materials and device technology which have led to these advances will be discussed.