GaAs FET MMIC switch reliability

The results of reliability tests on a GaAs FET monolithic microwave integrated circuit (MMIC) switch are presented. Accelerated life tests were performed under both high-temperature reverse-biased (HTRB) and RF-biased conditions. The dominant failure mode observed is an increase in the switch insertion loss. A high reliability level is demonstrated; a mean-time to failure (MTTF) of 4*10/sup 7/ hours at a temperature of 125 degrees C is predicted from statistical analysis of the results. The failure mechanism identified is gate metal interdiffusion into GaAs, with a log-normal failure distribution and an activation energy of 1.34 eV.<
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