Electrical and optical properties of compositionally spread MoInSnO thin films deposited by combinatorial RF magnetron cosputtering

Abstract

Using a combinatorial cosputtering method, we have deposited MoInSnO transparent conducting oxide (TCO) films at various gas ratios, constituent compositions, and film thicknesses to control the transparency window in the infrared and ultraviolet wavelength regions. The MoInSnO thin films showed a minimum sheet resistance of 8.25 Ω/□ and a transmittance of 90% (at 550 nm) when deposited at a substrate temperature of 350 °C, a film thickness of 298 nm, and an elemental composition ratio of 2.8/84.2/13.0 at. % (Mo/In/Sn, at. %). The carrier concentration of a MoInSnO film deposited in an Ar gas atmosphere was higher than that of an InSnO (ITO) film. The MoInSnO film also showed a shift of the transparency window to the short-wavelength region in the infrared range compared with the ITO film. However, the film resistivity increased and the transparency window shifted to the long-wavelength region with increasing O2 gas ratio. The absorption edge of the MoInSnO film in the ultraviolet region shifted to the short-wavelength region with increasing Mo content in the film.