Design and Characterization of the Deep-Trench, U-Shaped Field-Plate Edge Termination for 1200-V-Class SiC Devices

In this article, design and characterization of the deep-trench, U-shaped field-plate (DTUFP) edge-termination structure for 1200-V-class silicon carbide (SiC) devices are presented. A systematic numerical analysis shows that the trench depth, trench width, field-plate depth, and field-plate length are the four key structural parameters to determine the voltage blocking capability of the edge-termination structure. Experimental results demonstrate that the breakdown voltage of the proposed edge-termination structure can reach 1380 V when the edge-termination structure is well designed. Liquid crystal thermal measurement and destructive breakdown testing show that the ideal planar junction breakdown voltage has been achieved. The well-designed edge-termination structure has an ultrashort-edge width of 33 $\mu \text{m}$ , which is approximately 75% shorter than that of the conventional guard-ring and junction termination extension (JTE) edge-termination structures.