Understanding the degradation of InP/InGaAs heterojunction bipolar transistors induced by silicon nitride passivation

Abstract

The effect of SiN passivation on the electrical characteristics of InP/InGaAs HBT's has been investigated comprehensively. The major degradations of I-V characteristics identified in our InP/InGaAs HBT's are: (1) the decrease of current gain due to a significant increase in the forward base leakage current and (2) large increase of base-collector (B-C) and base-emitter (B-E) reverse leakage currents. We found that different physical origins should be attributed to these two degradation behaviors.