Comparison of neutron irradiation effects on the electrical performances of SiGe HBT and Si BJT

摘要

The change of electrical performances of silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) and Si bipolar junction transistor (BJT) was studied as a function of reactor fast neutron radiation fluence. Alter neutron irradiation, the collector current I_c and the current gain beta decrease, and the base current I_b increases generally for SiGe HBT. The higher the neutron irradiation fluence is, the larger I_b increases. For conventional Si BJT, I_c and I_b increase as well as beta decreases much larger than SiGe HBT at the same fluence. It is shown that SiGe HBT has a larger anti-radiation threshold and better anti-radiation performance than Si BJT. The mechanism of performance changes induced by irradiation was preliminarily discussed.