High breakdown voltage quasi-vertical PN diode with optimized multiple junction termination extensions

This study introduces a novel junction termination extension structure designed to enhance the breakdown voltage of GaN diodes. By employing a step-etched approach, we optimized the electric field distribution during reverse bias, leading to significant improvements in breakdown voltage capabilities. Both simulation and experimental results demonstrate that the proposed JTE structures, particularly those featuring elliptical boundary fittings, effectively mitigate electric field crowding, resulting in lower peak electric fields and enhanced device stability. The fabricated diodes achieved a breakdown voltage of 970 V, representing a substantial enhancement compared to traditional structures (560 V). This research contributes to the understanding of electric field management in GaN diodes and paves the way for future advancements in power electronics. The proposed JTE design also offers a promising strategy for optimizing the reliability and efficiency of high-power GaN devices.