Study of breakdown effects in silicon multiguard structures

The purpose of this work is to study layout solutionsaimed at increasing the breakdown voltage in silicon micro-stripdetectors. Several structures with multiple floating guards in different configurations have been designed and produced on highresistivity silicon wafers. The main electrical characteristics ofthese devices have been measured before and after irradiation.Both radiation-induced surface and bulk damage effects wereconsidered as well. The highest breakdown voltage was foundon devices featuring p+ guards without field plates. A simulationstudy has been carried out on simplified structures to evaluatethe distribution of the breakdown field as a function of the guardlayout. The aim was the design optimization.