Epitaxial Growth of Anatase-TiO2(001) Films

The anatase-TiO₂(001) thin films were epitaxially grown on 0.7 wt% Nb-doped SrTiO₃(001) substrates by pulse laser deposition (PLD) method^{39 (link)}. During deposition, The O₂ pressure was kept at 1.5 × 10⁻³Pa and the substrate temperatures were kept at a 650 °C. To obtain high quality 1 × 4 reconstructed surface, the anatase-TiO₂ films were grown slowly on SrTiO₃ substrate with deposition rate of ~1 nm/h. The typical thickness of the thin films was 20–30 nm. The as-grown anatase-TiO₂(001) samples were transferred between the PLD, STM and ARPES systems without exposure to air, via a portable ultrahigh vacuum transfer chamber with a battery powered ion pump to maintain a pressure better than 1 × 10⁻⁹ mbar.