Dose rate dependence of radiation-induced lattice defects and performance degradation in npn Si bipolar transistors by 2-MeV electron irradiation

摘要

Total-dose response of npn Si transistors by 2-MeV electrons is presented for different dose rates. The base current increases after irradiation, whereas the collector current decreases. Therefore, the current gain (β) decreases by irradiation. The degradation of electrical properties by 2-MeV electrons for low dose rate is higher than that for high dose rate. Similar dose rate dependence of the radiation-induced electron trap densities is observed by deep-level transient spectroscopy (DLTS) measurements.