High mobility cerium-doped indium oxide thin films prepared by reactive plasma deposition without oxygen

Cerium-doped indium oxide thin films were prepared by reactive plasma deposition on ultra-white glass substrates in pure argon atmosphere at room temperature. To improve the properties, the films were post-annealed at 180–280 °C with an oxygen-free atmosphere (vacuum and nitrogen) and with air atmosphere as reference. The as-deposited ICO films were amorphous and transformed to polycrystalline state after annealing treatment. And the mobility increases from 42 cm 2 V −1 s −1 to 93 cm 2 V −1 s −1 . The change in mobility is analytically attributed to the filling of oxygen vacancies and the reduction of ionized impurity scattering. After annealing, the average transmittance of the films is increased to 89% in the visible band (380–780 nm) and maintains above 85% in the near-infrared band (780–1200 nm), indicating that post-annealing is an effective way to improve the optical and electronic properties of the films. • The Cerium-doped indium oxide thin films are prepared by reactive plasma deposition under oxygen-free atmosphere at room temperature. And the films have low resistivity (3.3×10 −4 Ω cm) and high transmittance in the visible region (380–780nm) and near-infra region (780–1200nm), 87% and 85%, respectively. • To further improve the properties, the cerium-doped indium oxide thin films are annealed at 180°C–280 °C with an oxygen-free atmosphere, including vacuum and nitrogen. The mobility is increased to 88cm 2 V −1 s −1 and 93cm 2 V −1 s −1 , respectively. • Currently, the studies using reactive plasma deposition to prepare cerium-doped indium oxide thin films usually require the addition of O 2 , which limits the application of the films to some devices prone to oxidation. This study provides a new preparation process without oxygen. The cerium-doped indium oxide thin films with good optical and electrical properties have been obtained under oxygen-free atmosphere, which lays a foundation for the preparation without oxygen and broadens the ICO application.