Time Dependent Behaviour of Field Limiting Ring Passivation Systems

Off-state modelling is used extensively within Philips to design field limiting ring passivation systems for switching devices. However, no work has been done to ensure. that the quasistatic approach is valid in the transient case. This paper presents the results of fundamental simulations of the pulsed operation of a device with a field limiting ring. These are used to describe the ring´s time dependent behaviour in detail and so to identify possible pitfalls in the conventional design approach.