Stable Ohmic Contacts on SiC Devices for High Temperatures

Ti3SiC2 has been proposed as a mate- rial for ohmic contacts on SiC-based electronic and microelectromechanical devices intended to operate at temperatures >600 °C and/or in corrosive environments. Although SiC is stable and devices made of SiC are capable of functioning at elevated temperatures and in corrosive environments, the lack of stable ohmic contacts has been a barrier to the realization of SiC-based devices. Most metals react with SiC at high temperatures, forming metal silicides and/or carbides. At a minimum, these reactions cause contact resistances to change over time, affecting the performances of devices; in extreme cases, entire contact layers can deteriorate through oxidation, melting, evaporation, or balling up on surfaces.