Role of annealing environment on the performances of large area ITO films produced by rf magnetron sputtering

This paper presents the role of the deposition pressure and the rf power density on the optimization of the electrical, optical and structural properties of large area (30×40 cm2) indium-tin oxide films produced by rf magnetron sputtering, with growth rates exceeding 30 nm/min. The films were produced at room temperature under reactive plasma, followed by a thermal annealing in air or formic gas. The best films' uniformity (≤±5%), compactness and surface smoothness (preferential growth orientation along (222)); and electro-optical properties (resistivity and mobility, respectively, of about 7×10−4 Ω cm and 19.6 cm2 V−1 s−1, with transmittance of about 92%) were achieved using a rf power density of 0.92 W cm−2 and a pressure of 8.5×10−2 Pa, followed by its annealing in air by about 2 h at 773 K.