Bias and temperature stress reliability of InGaP/GaAs HBTs

Abstract

The reliability of InGaP/GaAs N-p-n HBTs with different base metal contact systems (Au/Zn/Au, Ti/Au, Ti/Pt/Au and the novel Ti/ZrB/sub 2//Au) under current and temperature stress is studied in this paper. We further report results of current stress on three p-GaAs doping impurities namely Zn, Be- and C. The effect of O/sup +//H/sup +/ and O/sup +//He/sup +/ ions, used in the fabrication of planar self-aligned HBTs, is also investigated in the stability of device dc current gain. The instability phenomena typical of each factor and their effects on the HBT characteristics are reported.