The Effect of Working Pressure on the Composition and Optical Properties of TiO2 Films Bombarded by N Ion Beams

N-doped TiO2 films were prepared by using N ion beams to bombard TiO2 films surface. By controlling the metal ultrahigh vacuum gat valve, only the N ion beams working pressure was adjusted from 0.1 to 0.9 Pa, with the step size of 0.2 Pa. The composition, chemical bond structure, and optical properties of N-doped TiO2 films were investigated. The result indicated that with increasing the ion source working pressure, more N ions were generated and bombarded with the surface TiO2 films, which could result in more N ions were doped into the films. So with increasing the ion source working pressure from 0.1 to 0.9 Pa, the N/Ti and O/Ti atom ratio increased and decreased monotonously from 0.37 to 0.49 and 1.49 to 0.61, respectively. Meanwhile, because of more N doped into films, the mean absorbency of N doped TiO2 films in the visible range also increased monotonously from 4.8% to 45.8%.