Solution deposition of ZnO thin films

Abstract

Abstract A solution deposition technique is investigated as an approach for formation of nanostructured ZnO films with tailored geometric shape and aspect ratio, electrical conductivity, and high optical transmittance. Having in mind thermodynamic particulars of ZnO precipitation from aqueous solutions, we show deposition of thin films of intrinsic ZnO with well-defined hexagonal wurtzite structure and with high optical transmittion in the visible region. Deposition of doped layers of Al:ZnO with aluminium concentration up to 3 wt% does not cause degradation of the wurtzite structure and sheet resistance of the films is near 8.0*102 Ω / □. After applying thermal annealing, the absorption edge gets sharper and optical band gap is found to be near 3.26 eV for direct transitions. Addition of the ethanol in the aqueous deposition solution leads to formation of ZnO nanostructured films with trigonal configuration.