Dopage et caractéri sat ion des couches minces d'oxyde de Zinc déposées par spray pyrolyse Ul trasonique

Dans ce travail, nous avons réalisé un dispositif de Spray Pyrolyse Ultrasonique, pour déposer des couches minces d’oxyde de zinc dopé Al. Nous avons classé deux séries : La première série: la source de dopage a été Le nitrate d'aluminium (Al (NO3)3) avec pourcentage varie entre 0% jusqu'à 8%. La deuxième série: la source de dopage a été Le chlorure d'aluminium (Al Cl3) avec pourcentage varie entre 0% jusqu'à 8%. Notons que, les autres paramètres sont fixés, tel que: la température et la concentration d’oxyde de zinc. L’objectif de ce travail est l’étude de l’effet de dopage sur les propriétés optiques, structurales et électriques des couches minces d’oxyde de zinc

Deposition and analysis of Zinc Oxide thin films elaborated using spray pyrolysis for photovoltaic applications

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

The synthesis and characterization of sprayed ZnO thin films: As a function of solution molarity

International audienceIn the present paper, the structural, electrical and optical properties of zinc oxide thin films were studied as a function of solution molarity. The ZnO thin films were deposited on glass substrates via the ultrasonic spray technique at 350°C. Polycrystalline films with a hexagonal wurtzite structure with (100) and (002) preferential orientation corresponding to ZnO films were observed. The optimal values of the crystallite size of the ZnO films were observed with (002) plan in 0.4 and 0.5 mol/l of solution molarity. All films exhibit an average optical transparency about 85% , in the visible region. The shift of optical transmittance towards smaller wavelength can be showed by the decrease of band gap caused by the change of crystallite size in polycrystalline. The maximum electrical conductivity of ZnO films was found of 2.29 (Ω.cm)–1 with 0.075 mol/l of solution molarity