Study of the TiSi interface formed by Ti deposition on a clean Si (100) surface: A periodic DFT study

A periodic Density Functional Theory (DFT) study using Generalized Gradient Approximation (GGA) of the Ti deposition on a clean Si (100) surface was carried out. The results indicate that Ti adsorbs preferentially on two Si dimers forming polar covalent bonds with four Si atoms. The analysis of the Density of states (DOS) indicates that Ti 3d orbitals hybridize with the surface orbitals near the Fermi level and each Ti atom transfers one electron to the surface even at concentration of 6.8 × 1014 Ti atom cm− 2. At this concentration, a quite stable TiSi monolayer is formed and subsequent additions of Ti atoms would initiate metallic Ti growth on the TiSi interface.