Proton radiation effects in vertical SiGe HBTs fabricated on CMOS-compatible SOI

Proton radiation effects in vertical SiGe HBTs fabricated on CMOS-compatible silicon-on-insulator (SOI) are investigated for the first time. Proton irradiation at 63 MeV is found to introduce base leakage current at low base-emitter voltage, delay the onset of Kirk effect at high injection, and increase the frequency response of SiGe HBTs on SOI. The latter two effects are in contrast to those found in conventional bulk SiGe HBTs. Proton irradiation also generates positive fixed oxide and interface charge in the buried oxide, which alters both AI-1 and B[V.sub.CEO] in the SiGe HBT by modulating the electric field in the collector region. Index Terms--HBT, radiation, SiGe, SOI.