TCAD study of DLC coatings for large-area high-power diodes

The most relevant transport features of doped diamond-like carbon (DLC) films have been implemented in a TCAD setup to provide a theoretical tool to assess the reliability expectations for high-voltage device passivation. Starting from the band structure and boundary conditions of a metal-insulator-semiconductor (MIS) device, trap states in the bandgap have been used to determine the characteristics of differently doped DLC layers against experiments. The role of the DLC as a passivation layer on top of the bevel termination of a high-voltage diode has been studied and compared with experiments. The breakdown voltage is significantly influenced by the properties of the DLC as clearly explained by the TCAD simulation results