The electrical behavior of Ni Schottky barrier formed onto heavily doped (ND> 1019 cm-3) n-type phosphorous implanted silicon carbide (4H-SiC) was investigated, with a focus on the current transport mechanisms in both forward and reverse bias. The forward current-voltage characterization of Schottky diodes showed a reduced barrier height (FB= 0.94 eV), with the current transport dominated by a thermionic-field emission mechanism. On the other hand, the reverse bias characteristics could not be described by a unique mechanism. In fact, under moderate reverse bias, implantation-induced damage is responsible for the temperature increase of the leakage current, while a pure field emission mechanism is approached with bias increasing. A numerical study of the potential distribution in a junction barrier Schottky (JBS) diode structure allowed demonstrating that metal/4H-SiC barriers on such heavily doped layers can find interesting applications in real devices.
17 Feb 2021
arXiv preprint arXiv:2102.08927