Performance Degradation and Defect Analysis of 2N3055 BJT Under High-Energy Lithium-Ion Irradiation

Abstract

This study examines the impact of 50 MeV lithium ion irradiation on 2N3055 BEL transistors under room temperature conditions. The devices were subjected to ion fluences ranging from 5×109 to 1×1013 ions/cm2. SRIM simulations estimated a range (R) of 310.24 μm, with electronic (Se) and nuclear (Sn) energy losses calculated at 0.408 MeV cm2 ^2/mg and 2.293×10−4 MeV cm2/mg, respectively. Deep Level Transient Spectroscopy (DLTS) identified defect types such as A-centers (EC−0.17 eV, trap concentration 1.29×1014 cm−3 and (Bi-Oi) complexes (EC−0.27 eV, trap concentration 4.59×1015 cm−3, with capture cross-sections of 2.18×10−19 cm2 and 5.00×10−18 cm2, respectively. Electrical characterization revealed a reduction in forward current gain (β=IC/IB) with increasing fluence, from pristine levels to a notable decline at 1×1013 ions/cm2. Carrier lifetime and effective lifetime diminished to 4.24×10−3 s and 4.74×10−6 s, respectively. Additionally, Gummel plots and excess base and collector current analyses confirmed performance degradation due to trap-assisted recombination. These findings elucidate the effects of ion-induced defects on transistor operation, contributing to the understanding of silicon device behavior in radiation-prone environments.