Thermal stability of TiN gate electrode for 4H-SiC MOSFETs and integrated circuits

In this research, the thermal stability of single stage amplifier based on 4H-SiC MOSFET with a TiN gate electrode was investigated. The results show that, after 100-hour aging at 400℃ in N2 ambient, the amplifier maintained good performance with stable voltage gain. The thermal stability of the amplifier results from the stability of Ni/Nb/4H-SiC source/drain ohmic contact, implanted load resistor, and MOS structure with the TiN gate electrode. The results obtained from the 4H-SiC MOS structure show that the interface trap density at the SiO2/SiC decreases during the aging process. While the gate leakage current of the capacitor based on Al gate electrode increases, it remains stable in structures with TiN gate electrodes after 100-hour aging. The results obtained in this study indicate that TiN is promising for the gate electrode of 4H-SiC MOSFETs for high-temperature applications.