Recent Developments in RF Overload Mechanisms, Burnout and Reliability of Low Noise GaAs FET Amplifiers

GaAs FET amplifiers are frequently subjected to RF overload in radar and communication systems. To satisfy reliability requirements, a comprehensive study of RF overload mechanisms is described which relates to catastrophic and non-catastrophic changes. Extensive catastrophic failure levels, typically 50 nJoules, have been established for 31 batches using improved device selection procedures. Non-catastrophic effects have been reduced to negligible levels with particular emphasis on phase distortion. Many amplifiers have successfully withstood destructively high RF powers (3W, 10 nsec) over many hundreds of hours and have demonstrated excellent reliability.