The effects of ionizing radiation on power-MOSFET termination structures

The effects of ionizing radiation on power-MOSFET termination structures were examined through two-dimensional simulation. A wide range of sensitivity to surface-charge density was found for various devices employing floating field rings and/or equipotential field plates. Termination structures that were both insensitive to surface charge and possessed a high breakdown voltage were identified. The results are compared with measurements made on selected structures. Insights into the design of optimum termination structures are obtained.>