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

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 radciation fluence.After neutron irradia-tion,the collector current Ic and the current gain β decrease,and the base current Ib increases generally for SiGe HBT.The higher the neutron irradiation fluence is,the larger Ib increases,For conventional Si BJT,Ic and Ib increase as well as β 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.