Simulation of SEE-induced charge collection in UHV/CVD SiGe HBTs

This paper presents quasi-3-D simulation results of SEE-induced charge collection in UHV/CVD SiGe HBTs. Depending on the bias and load condition, a significant fraction of electrons can be collected by the emitter rather than the collector. Most of the generated holes are collected by the substrate for deep ion strikes, and by the base for shallow ion strikes. A higher substrate doping can worsen the upset of the circuit function, despite the reduced total amount of charge collected. A lower substrate doping and a lower collector-substrate junction reverse bias are desired to improve SEU hardness.