Synergistic effect of total ionizing dose on single-event gate rupture in SiC power MOSFETs

The synergistic effect of total ionizing dose(TID) and single event gate rupture(SEGR) in SiC power metal–oxide–semiconductor field effect transistors(MOSFETs) is investigated via simulation. The device is found to be more sensitive to SEGR with TID increasing, especially at higher temperature. The microscopic mechanism is revealed to be the increased trapped charges induced by TID and subsequent enhancement of electric field intensity inside the oxide layer.

SEGR-and SEB-hardened structure with DSPSOI in power MOSFETs

Single event irradiation-hardened power MOSFET is the most important device for DC/DC converter in space environment application. Single event gate rupture （SEGR） and single event burnout （SEB）, which will degrade the running safety and reliability of spacecraft, are the two typical failure modes in power MOSFETs. In this paper, based on recombination mechanism of interface between oxide and silicon, a novel hardened power MOS- FETs structure for SEGR and SEB is proposed. The structure comprises double stagger partial silicon-on-insulator （DSPSOI） layers. Results show that the safety operation area （SOA） of a 130 V N-channel power MOSFET in single event irradiation environment is enhanced by up to 50% when the linear-energy-transfer value of heavy ion is a constant of 98 MeV-cm2/mg in the whole incident track, and the other parameters are almost maintained at the same value. Thus this novel structure can be widely used in designing single event irradiation-hardened power MOSFETs.

Simulation of the sensitive region to SEGR in power MOSFETs

Single event gate rupture（SEGR） is a very important failure mode for power MOSFETs when used in aerospace applications,and the cell regions are widely considered to be the most sensitive to SEGR.However, experimental results show that SEGR can also happen in the gate bus regions.In this paper,we used simulation tools to estimate three structures in power MOSFETs,and found that if certain conditions are met,areas other than cell regions can become sensitive to SEGR.Finally,some proposals are given as to how to reduce SEGR in different regions.