On the breakdown voltage temperature dependence of high-voltage power diodes passivated with diamond-like carbon

Abstract

Diamond-Like Carbon (DLC) is well established material for the passivation of high voltage negative bevelled power diode. In our previous works, the conduction mechanism of the DLC has been carefully described through the characterization and the physical modelling of Metal-Insulator-Semiconductor (MIS) structures. In addition, the effects on the breakdown voltage and leakage current have been clarified comparing the available experiments with numerical simulations. However, the role played by the DLC on the breakdown voltage temperature dependence is still lacking. In this work, we addressed the latter issue and found out an anomalous reduction of the temperature dependence which is clearly ascribed to the DLC behaviour. The temperature dependencies of carrier transport in the DLC have been further investigated in order to explain the experimental results. The observed effect might be related to the release of the trapped charges with increasing temperatures or to a different temperature dependence of the DLC mobility which is function of the distance from the Si/DLC interface. TCAD simulations are used to corroborate such assumptions.