Nitrogen as background gas in pulsed-laser deposition growth of indium tin oxide films at room temperature

Abstract

The use of nitrogen as background gas to assist pulsed-laser deposition in the fabrication of indium tin oxide (ITO) films at room temperature produces both highly conductive and transparent films (∼8×10 −4 Ω cm and ∼85% of transmittance), comparable to those obtained by using oxygen (∼4×10 −4 Ω cm and ∼90% of transmittance). Hall-effect electrical measurements, Rutherford backscattering spectrometry, X-ray diffraction and optical transmission on these films are reported. For the films with best conducting and transparent properties, atomic nitrogen is 5% of the atomic oxygen content in the films. The amount of nitrogen correlates to the amount of electron-carrier concentration in the films, which suggests that incorporation of nitrogen from the background gas plays an important role in the creation of oxygen vacancies—the main conduction mechanism in high-quality ITO films grown over substrates at room temperature.