The impact of laser energy, bias and irradiation positions on single event transients of InP HBT

The mechanism of single event transients in indium phosphide heterojunction bipolar transistors are studied with different laser energy, collector and irradiation positions based on a pulsed laser experiment. The area of the depletion region neutralized by the laser track determines the area of the funnel region, and affects the total charges collected by collector Q(Total). The total charge collection consists of the charge collected in the depletion region, the charges collected in funnel region, and the diffusion charges. The larger the area of the neutralized depletion region, the larger the area of the funnel region, thus, the more electron-hole pairs would be collected. The influence of laser energy, collector bias and irradiation positions on total charge collection is studied and discussed in detail.