Properties of multilayer transparent conducting oxide films

Multilayered transparent conducting oxide (TCO) film structures have been designed and fabricated to achieve both high conductivity and high transmittance in the visible spectrum. Double-layered TCO structures consisting of Sn-doped CdO and Sn-doped CdIn2O4, Cd-rich Cd2SnO4, or Ga-doped ZnO are discussed. By optimizing the thickness of the individual layers and the doping levels within those layers, an effective conductivity of 20600 S/cm and an average transmittance larger than 85% in the 400-700 nm range have been achieved for films epitaxially gown on MgO substrates. Bi-layer films consisting of Sn-doped CdO and Ga-doped ZnO have also been deposited on plastic substrates at room temperature with resistivities of similar to1 x 10(-4) Omega cm and an average transmittance of 80-85% in the visible range. These properties are attractive for future TCO applications. (C) 2004 Elsevier B.V. All rights reserved.