Doped SnO2 Transparent Conductive Multilayer Thin Films Explored by Continuous Composition Spread

Abstract

Mn-doped SnO2 thin films were fabricated by a continuous composition spread (CCS) method on a glass substrate at room temperature to find optimized compositions. The fabricated materials were found to have a lower resistivity than pure SnO2 thin films because of oxygen vacancies generated by Mn doping. As Mn content was increased, resistivity was found to decrease for limited doping concentrations. The minimum thin film resistivity was 0.29 Ω-cm for a composition of 2.59 wt % Mn-doped SnO2. The Sn−O vibrational stretching frequency in FT-IR showed a blue shift, consistent with oxygen deficiency. Mn-doped SnO2/Ag/Mn-doped SnO2 multilayer structures were fabricated using this optimized composition deposited by an on-axis radio frequency (RF) sputter. The multilayer transparent conducting oxide film had a resistivity of 7.35 × 10−5 Ω-cm and an average transmittance above 86% in the 550 nm wavelength region.