Demonstration of 4H-SiC Charge Balance Floating Junction Barrier Schottky Diode With High Baliga Figure of Merit

Abstract

Lower specific on-resistance (Ron,sp) and higher breakdown voltage (BV) are the primary goals of silicon carbide (SiC) power devices. This letter establishes a multi-layer floating junction device model based on charge balance theory and presents an optimized 4H-SiC floating junction Schottky barrier diode (CB-FJJBS) verified through experiments. With the utilization of charge balance theory, the device achieves a more balanced electric field(EF) distribution, thereby enhancing its breakdown characteristics. Notably, the device exhibits a Baliga figure of merit (BFOM, i.e., 4V ${_{\text {B}}} {^{{2}}}$ /Ron,sp) of 12.1 GW/cm2, a Ron,sp of ${\mathrm {4.9~\text {m}\Omega }} \cdot $ cm2 and a BV of 3.85 kV, representing the best performance among reported SiC floating junction (FJ) devices.