Zinc Oxide Thin Films Prepared by Atmospheric Pressure Chemical Vapor Deposition Using Zinc Chloride

Thin films of zinc oxide are deposited on silicon by Atmospheric Pressure Chemical Vapor Deposition (APCVD) method using zinc chloride precursor. The effect of time deposition on the structural, morphological, electrical, and optical properties of these films are investigated. The best films exhibiting appropriate properties for heterostructure solar cells application are obtained in the temperature range of 450 to 500°C. The X-ray diffraction spectra show the pattern of ZnO having an hexagonal structure with (002) preferred orientation. The morphology of the ZnO thin films shows nanorods with hexagonal symmetry normal to the substrate. Hall measurements indicate that decreased resistivity and increased conductivity resulted from the improvement of grain size and crystal quality. Under the optimal growth condition, ZnO thin films exhibit the lowest resistivity of 1.3×10-2 Ω.cm and average transmittance above 90% in the range 380-850 nm.