Effects of Sulfurization on the Properties of 4H-SiC Schottky Contacts

Abstract:

This paper reports on the effect of a sulfurization thermal process of the silicon carbide surface on the properties of Ni/4H-SiC Schottky barrier. In particular, the incorporation of sulfur (S) in the 4H-SiC near-surface region was observed at the process performed at 800 °C, without any significant effect on the surface morphology. On the other hand, Ni/4H-SiC Schottky contacts fabricated on the sulfurized 4H-SiC surface showed a 0.3 eV reduction of the average barrier height with a narrower distribution, with respect to the untreated sample. These results were explained by an increase of the 4H-SiC electron affinity after sulfurization, and a Fermi level pinning effect.

• Periodical: Materials Science Forum (Volume 1159)
• Pages: 1-7
• DOI: https://doi.org/10.4028/p-j9hDA2
• Online since: September 2025
• Authors: Fabrizio Roccaforte*, Marilena Vivona, Salvatore Ethan Panasci, Salvatore di Franco, Giuseppe Greco, Patrick Fiorenza, Attila Sulyok, Antal Koos, Béla Pécz, Filippo Giannazzo
• Keywords: Fermi Level Pinning, Kelvin Probe Force Microscopy, Schottky Barrier, Sulfurization

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