Reliability of self-aligned, ledge passivated 7.5 GHz GaAs/AlGaAs HBT power amplifiers under RF bias stress at elevated temperatures

Abstract

We report a two-temperature RF bias stress test on nominal 1.2 W 2.5 GHz GaAs/AlGaAs HBT unit cell amplifiers. MTTFs of 2020 and 1340 hours were obtained at Tj=218/spl deg/C and 245/spl deg/C, respectively, under nominal input bias. An activation energy of 0.42 eV is estimated, consistent with published results for similar devices under DC bias stress.