Response Mechanisms of Additional Displacement Defects in Oxides to Ionization Damage in Bipolar Transistors

When evaluating the radiation damage of charged particles to bipolar junction transistors (BJTs), the additional displacement defects caused by charged particles in oxide cannot be ignored. In this article, we demonstrate that the additional displacement defects can enhance or weaken the ionization damage level of BJTs. Additional displacement defects always weaken ionization damage in p-n-p BJTs and may enhance it in n-p-n BJTs. In addition, in the same BJTs, the response of additional displacement defects in oxide at different depths to ionization damage is also different, which strongly depends on the depth of additional displacement defects. Additional displacement defects in oxide show different results in response to ionization damage in different types of BJTs, which brings complexity to the accurate assessment of the radiation hardness of BJTs. Therefore, in this article, three different types of BJTs are analyzed in detail. In their oxides, the response mechanism of additional displacement defects to ionization damage is analyzed in detail, which provides a reference for improving the evaluation accuracy of more types of BJTs.