Dual-Material Gate Double-Gate (DMDG) structure is promising for future ultra-scaled devices thanks to its capability to reduce SCEs and HCEs. This is due to a step in the surface-potential profile which screens the source side of the channel from drain-potential variations and reduces the drain electric field. In this work, we investigate the DMDG sensitivity to single-event transients. The impact of dual gate materials on the bipolar gain is particularly addressed. We show that DMDG is naturally less radiation immune than usual single-material DG (SMSG) devices.