Structural, Optical, and Electrical Properties of SnO2-CdO-In2O3 Films Prepared by Magnetron Co-sputtering

SnO2-CdO (SCO) films and SnO2-CdO-In2O3 (SCIO) films are successfully deposited on Si (100) and glass substrates by radio frequency and direct current magnetron co-sputtering. The films are characterized by X-ray diffraction, scanning electron microscope, energy-dispersive X-ray spectroscopy, ultraviolet visible near-infrared spectroscopy, and four-point probes. SCO films exhibit Cd2SnO4 (011) preferred orientation, and the SCO film deposited at the sputtering power of 80W exhibits excellent crystalline quality and transmittance. The arrangement of clusters changes from sparse to dense when the indium element concentration increases. The resistivities of SCIO films are of two orders of magnitude lower than those of the SCO films. However, the visible light transmittances decrease slightly and the optical bandgap values decrease from 5.00 to 4.85 eV. The results indicate that the indium element plays an important role in improving the electrical properties of SCO films. SCIO films are expected to be a good candidate for transparent conductive films.