Neutron induced single-event burnout of IGBT

Cosmic-ray neutrons can trigger a single-event burnout (SEB), which is a catastrophic failure mode in power semiconductor devices. It was found experimentally that the incident neutron induced SEB failure rate increases as a function of the applied collector voltage in an insulated gate bipolar transistor (IGBT). Moreover, the failure rate increased sharply with an increase in the applied collector voltage when the voltage exceeded a certain threshold value. Transient device simulation showed that the onset of impact ionization at the n^- drift/n⁺ buffer junction (nn⁺ junction) can trigger turning-on of the inherent parasitic thyristor, and then SEB subsequently occurs. In addition, it was analytically derived that reducing the current gain of the parasitic transistor was effective in increasing the SEB threshold voltage. Furthermore, `white´ neutron-irradiation experiments demonstrated that suppressing the inherent parasitic thyristor action leads to an improvement of the SEB threshold voltage.