On the short and long term degradation of GaInP/GaAs heterojunction bipolar transistors

This work deals with the short and long term effects of a current stress pe rformed at room temperature on Carbon doped GaInP/GaAs heterojunction bipol ar transistors, The investigation has been carried out by means of DC chara cterizations and low frequency noise (LFN) measurements in the 250 Hz-100 k Hz frequency range. During the stress the devices were biased in the forwar d active region, a collector-emitter voltage of 7.7 V and a collector curre nt density of 2.2 x 10(4) A/cm(2) were imposed. The effect of the stress on the DC and LFN characteristics were compared and discussed in terms of two recombination mechanisms, The discussion points out that both extrinsic an d intrinsic recombination processes have to be taken into account in order to justify the short and long term effects of the electrical stress. (C) 19 99 Elsevier Science Ltd. All rights reserved.