Methods of calculating the field enhancement depending on void shape

This paper discusses how the field enhancement in a void is influenced by the void´s shape. Formulas are presented which describe the field enhancement in different voids. For one void shape the field in the void was computed with the simulation software MAFIA (Maxwell finite integration algorithm) and the results are compared with solutions found utilizing an analytic formula based on the results of Hall and Russek. The possibilities and limitations of each formula are presented with special emphasis on the Hall and Russek formula