Titanium oxide films on Si(100) deposited by e-beam evaporation

Titanium oxide films with a thickness of a 400 nm were deposited on p-type Si(100) at room temperature by e-beam evaporation, and titanium dioxide was evaporated in oxygen environment at a pressure of 2x10(-6)-4x10(-5) Torr. Effects of oxygen flow rate (FO2,) on the properties of the films, such as surface roughness, composition, and chemical states, have been investigated. The root-mean-square surface roughness of the films increased with increasing FO2 UP to 20 seem, and then decreased over 20 seem. X-ray diffraction patterns show that the titanium oxide films are amorphous. Oxygen resonance backscattering spectroscopy shows that all films are oxygen rich, i.e., relative atomic ratio (Co/C-Ti) of the films ranged from 2.05 to 2.25. But the x-ray photoelectron spectroscopy (XPS) analysis shows that the titanium oxide films were oxygen deficient. The ratio of oxygen to titanium (Co-2/C-Ti) of the films calculated by XPS ranged from 1.87, to 1,93, XPS shows that there exist only Ti3+ and Ti4+ charge states in the film. Ti4+ states of the films are nearly constant at 0.47 up to O-2 flow rate of 20 seem, and then slightly increase with increasing O-2 flow rate. Although rutile TiO2, is used as a starting material, titanium K-edge x-ray absorption near-edge spectroscopy (XANES) spectra show that the structure of the TiO2-x, films grown in oxygen environment are amorphous. The Ti K-edge XANES spectra from the films is the same regardless of FO2. (C) 2000 American Vacuum Society. [S0734-2101 (00)03006-2].