Thickness Dependence of Resistivity and Optical Reflectance of ITO Films

Indium-tin-oxide (ITO) films deposited on crystalline silicon wafer and Corning glass are prepared by direct-current magnetron sputtering method at room temperature with various thicknesses. The thickness dependences of structure, resistance and optical reflectance of ITO films are characterized.
The results show that when the film thickness is less than 40nm, the resistivity and optical reflectance of the ITO film changes remarkably with thickness. The optoelectrical properties trend to stabilize when the thickness is over 55nm. The GXRD result implies that the ITO film begins to crystallize if only the thickness is large enough.