Nickel Ohmic Contacts Formed on 4H-SiC by UV Laser Annealing

Laser Thermal Annealing (LTA) is a key process step to improve the 4H-SiC devices by reducing their on-state resistance. In this study, we investigate the electrical, structural and morphological properties of nickel contact fabricated by LTA. A contact formed by a classical Rapid Thermal Annealing (RTA) was also fabricated as reference. Based on structural analysis, the phases formed by LTA do not match with RTA sample ones that has better ohmic properties. Nevertheless, the LTA contacts reach a specific contact resistance of 2.4×10 -5 Ω.cm 2 for an annealing at 4.75 J.cm ‑2 , which represents a significant improvement in comparison with our previous contacts fabricated with the same experimental protocol using titanium.