A novel edge termination structure for achieving the ideal planar junction breakdown voltage

摘要

In this paper, a novel edge termination structure for achieving the ideal breakdown voltage of the planar junction is numerically analyzed and experimentally demonstrated. The structure features a trench filled with BCB (BenzoCycloButene) dielectric, and is fabricated along with a high-voltage p-n junction diode. Furthermore, a sloped field plate (connected to the anode electrode) is buried inside the trench. In the blocking state, this field plate modulates the electric field distribution along the trench and shifts the location of high field to the p-n junction in the active region to achieve the ideal breakdown voltage of the planar junction. The breakdown voltage of the fabricated device is measured to be 755 V with a record-short edge termination length of 35 μm which is less than one-fifth of that of conventional guard ring termination structures.