A Comparative Study on Heavy-Ion Irradiation Impact on p-Channel and n-Channel Power UMOSFETs

The leakage current degradation, single-event burnout (SEB), and single-event gate rupture (SEGR) behaviors induced by the heavy-ion irradiation in p-Channel and n-Channel power U-shaped metal–oxide–semiconductor field-effect transistors (UMOSFETs) are comparatively investigated in this article via experiments and simulations. The SEB and SEGR performances of a commercially available −100-V-rated p-Channel UMOSFET are tested under heavy-ion irradiation. The experimental results show that the sample devices can be prevented from the drain leakage current or gate leakage current degradation under the bias conditions of
$V_{\mathrm {GS}} = -100$
V and
$V_{\mathrm {GS}} = 0$
. However, a severe gate leakage current degradation can occur at
$V_{\mathrm {DS}} = -100$
V when
$V_{\mathrm {GS}} \ge 5$
V. In addition, the SEB and SEGR characteristics of a 100-V-rated n-Channel UMOSFET are obtained by simulations. The simulation results indicate that a p-Channel UMOSFET can achieve much better robustness against heavy ions compared with an n-Channel UMOSFET. Further, the leakage current degradation and failure mechanisms induced by heavy-ion irradiation are investigated via simulations. Finally, an effective method, which enlarges the width and depth of the source contact trench, is introduced to enhance the SEB tolerance of an n-Channel UMOSFET. The simulation result shows that the SEB threshold voltage can represent an increase of 23.1% with the hardening method.