Thermally Stable Ohmic Contact to p-Type 4H-SiC Based on Ti3SiC2 Phase

In this study, the electrical properties of Ti3SiC2 based ohmic contacts formed on p-type 4H-SiC(0001) 4°-off substrates were studied. The Ti3SiC2 thin films were grown by thermal annealing (from 900°C to 1200°C) of Ti50Al50 layer deposited by magnetron sputtering. XRD analyzes were performed on the samples to further investigate the compounds formed after annealing. Using TLM structures, the Specific Contact Resistance (SCR) at room temperature of all contacts was measured. The temperature dependence (up to 600°C) of the SCR was studied to understand the current mechanisms at the interface and to determine the barrier height value by fitting the experimental results using the thermionic field emission theory. Aging tests showed that Ti3SiC2 based contacts were stable up to 200h at 600°C under Ar.