Room Temperature Synthesis of Transparent and Conducting Indium Tin Oxide Films with High Mobility and Figure of Merit by RF-Magnetron Sputtering

Abstract

Tin doped indium oxide (ITO) films with high conductivity and charge carrier mobility were deposited at room temperature using RF-magnetron sputtering, without any post annealing treatment. It is observed that structural, optical, morphological and electrical properties of these ITO films depend on deposition time. All the synthesized films show optical transmittance > 90% and band gap of ∼ 3.6 eV. A change in crystal orientation from (222) to (400) with slight shift of peaks toward lower 2θ has been observed with the increase in deposition time. The synthesized films are compact, uniform and free from cracks. Moreover, there was an increase in grain size and shape with the progress in deposition time. Synthesized ITO films with (400) orientation have high conductivity (∼ 2 × 103 Ω−1 cm−1), high charge carrier mobility (∼ 348 cm2 V−1 s−1) and a high figure of merit (104 × 10−3 Ω−1). The synthesized thin films can have prospective applications in opto-electronic devices such as solar cells, light emitting diodes, etc.