Comprehensive trade-off strategy for SiC MOSFETs using buried-MOS configuration

While SiC MOSFETs have entered commercial markets, they still rely on specialized device structural approaches tailored to meet specific application demands. The intricate and interdependent relationships among diverse physical parameters of SiC MOSFETs have not been fully elucidated to address the trade-offs that influence each other. This study aims to clarify these complex relationships and propose a well-balanced trade-off strategy. The proposed Buried-MOS configuration ensures a harmonious balance among lower R on,sp , reduced C GD , and milder E OX without compromising BV , thereby optimizing the interconnected physical parameters of SiC devices and significantly enhancing their high-voltage, high-frequency performance and reliability. The experimental results quantitatively demonstrate the advantages of the Buried-MOS structure: (HF-FOM) ( R DS,on × C GD ) by 2.5×, HF-FOM ( R DS,on × Q GD ) by 2.2× and Baliga figure of merit (BFOM = 4 BV 2 / R on,sp ) by 1.7× compared with the conventional BOX-MOS. Importantly, this approach embodies both theoretical significance and practical applicability, compatible with existing large-scale manufacturing processes and requiring no additional steps.