Developing the Guard Ring Topology of Power Silicon Diodes with a Blocking Voltage of up to 6.7 kV

Abstract

High-voltage fast recovery diodes (FRDs) are characterized by a small forward voltage drop and low power dissipation. The main characteristics of such diodes is the reverse blocking voltage or the breakdown voltage. The aim of this work is to develop a guard ring topology allowing us to obtain the maximum possible blocking voltage of the diode and definite localization of the breakdown place under the conditions of the standard technological processes and without using new materials or substrates. The topology of the high-voltage part of silicon fast recovery power diodes is developed to obtain the maximum reverse blocking voltage. The calculations are carried out in the TCAD environment in the structure editor of which we included a program for the automatic creation of device models with dimensions of about several millimeters. The arrangement of guard rings is calculated according to the proposed principle allowing us to obtain power diodes with different breakdown voltages. The topology is developed so that the breakdown occurs under the edge of the active region, which guarantees the absence of catastrophic failures of the device. Power fast recovery diodes manufactured according to the proposed topology have the maximum reverse blocking voltage within the range of 3.3–6.7 kV, which indicates the reliability of the calculation methodology.