Analytic model for field-plate-edge breakdown of planar devices terminated with field plate and semiresistive layer

An analytic model for calculating the surface field of high-voltage devices terminated with a field plate and SIPOS (semiresistive polycrystalline) layer is presented. This allows determination of the breakdown voltage at the field-plate edge in terms of the field-plate length, the effective length of the SIPOS layer, the thickness of oxide buffer layer, and the silicon doping concentration. The results show a fair agreement with the numerical simulations as well as the experimental results reported.