Design and Analysis of a Dual-Step Field-Plate Terminated 4H-SiC Schottky Diode Using SiO2/High-K Dielectric Stack
Silicon carbide (SiC) field plate terminated Schottky diodes using silicon dioxide (Si02) dielectric experience high electric field in the insulator and premature dielectric breakdown, attributed to the lower dielectric constant of the oxide. This problem can be addressed by using high-k dielectrics such as silicon nitride (Si3N4) that will reduce the field, increase the breakdown voltage and consequently improve the lifetime of the devices. While the advantages of single step field-plate terminated diodes are well-known, the breakdown voltage can be improved even further using a dual-step field-plate termination. Our 2D-numerical simulations using MEDICI have shown an improvement in breakdown voltages in excess of 25% compared to the traditional single-step field-plate terminated diodes.
Robert P. Devaty, David J. Larkin and Stephen E. Saddow
A. Kumta et al., "Design and Analysis of a Dual-Step Field-Plate Terminated 4H-SiC Schottky Diode Using SiO2/High-K Dielectric Stack", Materials Science Forum, Vols. 527-529, pp. 1171-1174, 2006