3.3 kV SiC JBS diodes employing a P2O5 surface passivation treatment to improve electrical characteristics

3.3 kV Schottky barrier diodes and Junction Barrier Schottky diodes have been fabricated, employing a phosphorous pentoxide $\left(P_{2}O_{5}\right)$ surface treatment prior to metal deposition in an attempt to further condition the power device’s interface. For SBD structures, the treatment consistently reduces the leakage current in molybdenum, tungsten and niobium SBDs, for the tungsten treatment by more than four orders of magnitude. X-ray photoelectron spectroscopy (XPS) analysis on the treated SBD interface revealed formation of a metal phosphate between $P_{2}O_{5}$ and the metal. When compared to an untreated sample, the $P_{2}O_{5}$ treatment has increased the valence band to fermi level offset by 0.2 eV to 3.25 eV, indicating that the treatment results in a degenerately n-doped SiC surface. When applied to fully optimised 3.3 kV JBS power structures utilizing a hybrid JTE design, $P_{2}O_{5}$ treatments improved blocking capabilities across the entire dataset by as much as 1,000 V.