A New Perspective on the Plasma Clearance during Overcurrent Reverse Recovery of Silicon High-Voltage Power Diodes

Using 2D mixed-mode device simulation, this paper examines the overcurrent turn-off or reverse recovery of a 3.3-kV silicon fast recovery diode. Simulation results show that cathode-side current filaments (CCFs) play more roles than expected during the overcurrent reverse recovery under severe conditions. The actions of the CCFs include cutting and squeezing the residual plasma within the n
^í
region, and promoting the formation of anode-to-cathode solitary current filaments. Both the width of the lateral resistance zone at the edge of the main junction and the backside n
⁺
doping can affect the evolving patterns of the residual plasma, CCFs and anode-to-cathode filaments, which in turn determines the intensity of the final solitary filament, and thus the chance of survival of the device.