Reduction of Specific Contact Resistance on n-Type Implanted 4H-SiC Through Argon Inductively Coupled Plasma Treatment and Post-Metal Deposition Annealing

The effects of Ar inductively coupled plasma (ICP) treatment on the Ohmic contact on n⁺-implanted SiC were investigated in this letter. The effects of ICP treatment were negligible on the Ni-silicide contact, because the treated surface layer was consumed during silicide formation. However, for the Ti contact, as the annealing temperature increased, the ion-bombardment-induced damage layer transformed to a uniform amorphous C-rich layer, and the specific contact resistance of the ICP-treated Ti contact decreased to 8.3 × 10^-7 Ω-cm² after 600 °C annealing. This is the lowest value achieved at such a low process temperature. Thus, appropriate ICP treatment and annealing can be used to form low-resistivity Ohmic contacts with a lower thermal budget that are comparable with Ni-based silicide Ohmic contacts.