Design and Analysis of DC/DC Boost Converter using Vertical GaN Power Device based on Epitaxially Grown GaN-on-sapphire

In this study, a high-performance vertical gallium nitride (GaN) power transistor was designed by using two-dimensional technology computer-aided design simulator. In addition, the vertical GaN transistor is used to analyze the DC/DC boost converter. Systems requiring high voltages of 1000 V or more, such as electric vehicles, need wide devices to achieve a high breakdown voltage when using conventional power devices. However, vertical GaN transistors can be fabricated with a small device area and a high breakdown voltage. The proposed device has an off-current of 413 pA/cm², an on-current of 22 kA/cm², and a high breakdown voltage of 1693 V due to good gate controllability and the undoped-GaN layer. The designed device was used to construct a boost converter that doubled the input voltage and its characteristics were examined. The boost converter produced an output voltage of 1955 V and the voltage conversion efficiency was high at 97.75 %.