Investigating the Effects of Individual Neutron-Induced Defects in Bipolar Junction Transistors

This study investigates neutron-induced displacement damage in bipolar junction transistors (BJTs) using technology computer-aided design (TCAD) models informed by deep-level transient-spectroscopy (DLTS) data. These models are calibrated and validated against experimental measurements performed at various neutron fluences. Both n-p-n and p-n-p transistor configurations are studied to analyze the effects of individual traps on carrier recombination and base leakage currents. In n-p-n transistors, deep traps (0.42 eV from the conduction band) dominate at low voltages, while shallow traps (0.17 eV from the conduction band) become prominent at higher voltages. Conversely, p-n-p transistors have base leakage current predominantly due to deep-level traps. The study observes a notable trend in trap density versus fluence, characterized by a linear relationship on a log-log scale. These insights into defect evolution under radiation conditions are crucial for optimizing semiconductor device reliability and performance in radiation-prone environments.