3.1.6 Metal-Semiconductor Contacts

Metal-semiconductor contacts in SiC can possess rectifying or non rectifying behavior depending on the formation of the contacts (Section 2.5), which is to first order function of the semiconductor doping concentration and surface polarity (Si- or C-face). There are few devices in SiC such as the MESFET and the Schottky diode that actually need Schottky contacts (require low doping concentration of $\leq10^{17}$ cm$^{-3}$). Most other SiC devices as well as integrated circuits need ohmic contacts (require high doping concentration of $\geq10^{19}$ cm$^{-3}$) to make connections to other devices in an electronic system.
T. Ayalew: SiC Semiconductor Devices Technology, Modeling, and Simulation