SUBSTRATE-TEMPERATURE DEPENDENCE OF ZNO FILMS PREPARED BY ULTRASONIC SPRAY-PYROLYSIS

Strongly c-axis oriented zinc oxide (ZnO) films were deposited on sili con wafers coated with SiO2 or 7059 coming glass substrates from a sol ution containing zinc acetate. The films were deposited in a hot wall reactor by the pyrolysis of an aerosol produced by an ultrasonic gener ator. The crystallinity, surface morphology and composition of the fil ms were studied using X-ray diffraction analysis (XRD), scanning elect ron microscopy (SEM) and Rutherford back-scattering spectrometry (RBS) , respectively The influences of the concentration of zinc acetate in the solution and the substrate temperature on the crystallinity of the films were studied. The films grown at a substrate temperature of 350 -450 degrees C from a 0.03 M/l solution exhibited strong (002) orienta tion with a very smooth surface. The resistivity of the films was arou nd 10 Omega . cm. Oxidation resulted in a 10,000-fold increase in the resistivity.