Dual functional distribution of failure in GaAs multichip microwave monolithic integrated circuits (MMICs)

A definitive separation of bimodal failure distribution functions for MMICs has been obtained as a result of microwave accelerated life testing. The circuit, a 2-8-GHz monolithic amplifier, showed a very strong early failure pattern related only to passive component degradation. Using the concept of multifunctional distribution it was possible to separate the early failure pattern and to relate it to degradation of the off-chip capacitors. The main failure distribution was related to gate and ohmic contact electromigration of the MMIC active components. When the data analysis includes the early failures, a mean time to failure (MTTF) of less than 1*10/sup 5/ is obtained.<
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