Proton-induced dielectric breakdown of power MOSFETs

Proton-induced dielectric breakdown of vertical power metal oxide semiconductor field effect transistors (MOSFETs) is reported for the first time and compared to the heavy-ion-induced gate rupture response. Power MOSFETs from five variants were fabricated with nominal gate oxide thicknesses of 30, 50, 70, 100, and 150 nm. Devices from each variant were characterized to several heavy ion beams as previously reported. and then other devices from each variant were subsequently characterized to 200-MeV protons, as reported here. In addition, a limited characterization was performed using 44-MeV protons. Employing a similar test methodology, failure thresholds for the onset of proton-induced dielectric breakdown were determined for each gate oxide variant. The measured proton-induced dielectric breakdown thresholds induced by 200- and 44-MeV protons are compared to the measured heavy-ion induced failure thresholds.