TRANSPARENT CONDUCTING Al AND In CODOPED THIN FILM DEPOSITED BY SPRAY PYROLYSIS

Transparent conducting Al-In codoped ZnO thin films were successfully synthesized onto glass substrates by spray pyrolysis technique. The influence of doping and codoping on the structural, optical and electrical properties was investigated. X-ray diffraction results showed that the samples have the hexagonal Wurtzite structure with a preferred orientation toward the c-axis. No peaks belonging to In and Al or their oxides was observed in the limit of XRD technique detection. EDS analysis confirmed the presence of In and Al elements in ZnO thin films. The atomic percentage of In and Al elements was nearly equal to their nominal stoichiometry. The surface morphology of the codoped films showed well-defined hexagonal grains. Examination through transmission electron microscopy depicted that these films consists of an agglomeration of small grains with hexagonal shape. A high transmittance above 75% and electrical resistivity around 3x10(-2) Omega.cm were reached after annealing.