Radiation Hardness Test of BJTs under Designated Application

Abstract—Performance and properties of bipolar junction transistor (BJT) devices are affected due to the harsh radiation environment. This report reviews the typical effects occurring in BJT devices due to irradiation with x-rays. The defect parameters on the device tested is obtained by in situ experimental technique. In order to study the self-annealing behaviour in BJTS due to ionizing and displacement modifications, damage efficiencies at different bias current levels are compared. The study reveals that higher gain degradation dispersion occurs at lower bias current level. Damage creation in the BJTs is dominated by the excitation mechanism of valence electron to the conduction band. This leads to the production of a large number of excited atoms and increases the holes in the valence band. The increase of holes in the base region due to trapping will increase the probability of recombination and reducing the number of electrons that reaches the collector region. Index Terms—BJTs, x-rays, in situ, self-annealing, excitation, recombinatio