Unified Analysis of Degraded Base Current in SiGe:C HBTs after Reverse and Forward Reliability Stress

A 150GHz f_T/f_max SiGe:C NPN heterojunction bipolar transistor was subjected to reverse reliability stress, high current forward stress and mixed-mode stress. A base current degradation comparison puts in evidence a Shockley-Read-Hall leakage mechanism for all the degradation modes, giving a unified basis for device degradation physics study. Temperature and recovery behavior, acceleration factors and defect location studies add to discussion on aging models in SiGe:C HBTs