Proton irradiation of GaN transistor based power supply operating in the linear region

This paper describes the board level testing of a linear power supply based on SiC Junction Barrier Schottky diodes and GaN Hybrid Drain embedded Gate Injection Tran-sistors in a 186 MeV proton beam to evaluate the potential sensitivity to SEEs. The GaN components of the power supply have been individually tested against cumulative radiation dam-age in passive mode (i.e. unbiased) up to a 1 MeV(Si) neutron equivalent fluence of $3.4\times 10^{14}$ n/cnr2, It is planned for the lighting system to be in the off state during normal accelerator operation, however the potential consequences of accidental or inadvertent powering the lighting must also be understood. If tolerant to SEEs, the power supply can also be potentially used as a current-controlled power supply for other applications in harsh radiation environments. In this context, board level testing is used to rapidly confirm the radiation hardness and expected performance designed into the power supply. Boards were irradiated in a uniform field and no failures were observed on test devices up to the maximum fluence of $1.0\times 10^{11}\mathrm{p}/\text{cm}^{2}$.