Experimental and theoretical analysis of ZnO/Au/ZnO transparent conducting thin films

The underlying mechanism of conduction of ZnO/metal/ZnO multilayer structure film was analyzed by using quantum statistical theory and a theoretical model of resistivity was proposed. The resistivity of multilayers significantly relies on the work function and the thickness of interlayer metal. When the work function of metal is higher than that of ZnO the electron flows to the semiconductor much easier. The metal Au, work function 5.4 eV, was be chosen as the middle layer. A high-quality transparent electrode of ZnO/Au/ZnO structure was obtained, with a resistivity as low as 7.0 × 10－４ Ω cm, a high transmittance of 80% in the visible frequency region and a thickness of only 50 nm. The experiment date is agrees well with theoretical result.