Electric field breakdown mechanisms in high power epitaxial 4H-SiC p-n junction diodes

Silicon carbide (SiC) is an excellent semiconductor for the fabrication of high power and high temperature electronic devices. SiC pn junctions are critical components of SiC high power devices and circuits. However, the high electric field behavior of SiC p-n junction structures is not well characterized. The study of the high field breakdown mechanisms of SiC p-n junction plays an important role in determining the proper design of SiC high power p-n junction-based devices. We have determined the high field breakdown behaviors of several types of 4H-SiC epitaxial p-n junction diodes of different design. In our efforts to increase the breakdown voltage, we have found that oxide passivation did not substantially affect the breakdown voltage but edge termination using argon ion implantation is effective in improving the breakdown voltage of SiC-p-n junction diodes