Undoped and doped (by Al and In) ZnO thin films were deposited via two types of spray pyrolysis technique, ultrasonic and pneumatic onto glass substrates, to investigate the effect of several factors on the structural, optical and electrical properties of ZnO thin films. In the first part, we have deposited set samples of ZnO thin films using ultrasonic spray pyrolysis process with various start solution molarities for undoped ZnO and various doping concentrations for Al and In doped ZnO films. In the second, ZnO thin films were deposited using pneumatic spray pyrolysis process with two deferent spray pressure (1 and 1,5 bar) and various substrate temperatures for each pressure; also ZnO films with various aluminium doping rates were prepared. As well as, All the ZnO thin films were analyzed by assorted techniques X-ray diffraction, X-ray Dispersive Spectroscopy (EDS), SEM, UV-Vis, Hall Effect, four and two probes technique. This study allowed us to get ZnO thin films with very important structural, optical and electrical properties, which are very promising in photovoltaic applications
