Negligible influence of C-related defect on the barrier properties of Ti3C2T2/SiC contacts: A first-principles study

Abstract

The nature of the metal/semiconductor (M/S) contact (Ohmic or Schottky) in electronic devices can greatly affect the electronic properties of the component. The effective regulation of Schottky barrier height (SBH) has great importance for the successful operation of any electronic device. This paper demonstrates that the Ti₃C₂T₂/SiC interface can effectively suppress the Fermi level pinning (FLP) effect through van der Waals stacking. By investigating the effects of the most probable C-related defect, namely carbon substitutional doping at silicon sites (C_Si defects), on the contact performance of Ti₃C₂T₂/SiC. It is found that C_Si defects do not affect the contact type of Ti₃C₂T₂/SiC and have little impact on the tunneling barrier. In addition, the SBH of Ti₃C₂T₂/SiC could be modulated by a vertical electric field, without altering the tunneling barrier. The modulation is also not influenced by the C_Si defects. Furthermore, based on the calculated Schottky and tunneling barriers, Ti₃C₂(OH)₂ is the most compatible electrode with 2D SiC among the Ti₃C₂T₂, even in the presence of C_Si defects in SiC.