Au-Based Transparent Conductors for Window Applications: Effect of Substrate Material
Thin films of Au were made by sputter deposition onto glass substrates with and without transparent and electrically conducting layers of SnO2:In. The Au films were up to ~11 nm in thickness and covered the range for thin film growth from discrete islands, via large scale coalescence and formation of a meandering conducting network, to the formation of a more or less “holey” film. Scanning electron microscopy and atomic force microscopy showed that the SnO2:In films were considerably rougher than the glass itself. This roughness influenced the Au film formation so that large scale coalescence set in at a somewhat larger thickness for films on SnO2:In than on glass. Measurements of spectral optical transmittance and electrical resistance could be reconciled with impeded Au film formation on the SnO2:In layer, leading to pronounced “plateaus” in the near infrared optical properties for Au films on SnO2:In and an accompanying change from such two-layer films having a lower resistance than the single gold film at thicknesses below large scale coalescence to the opposite behavior for larger film thicknesses.
Pietro VINCENZINI, David S. GINLEY, Giovanni BRUNO, Attilio RIGAMONTI and Nikolay ZHELUDEV
P. C. Lansåker et al., "Au-Based Transparent Conductors for Window Applications: Effect of Substrate Material", Advances in Science and Technology, Vol. 75, pp. 25-30, 2010