Effect of Ag thickness on electrical transport and optical properties of indium tin oxide–Ag–indium tin oxide multilayers

We report the dependence of electronic and optical properties on the Ag thickness in transparent conductive indium tin oxide (ITO)-Ag-ITO (IMI) multilayer films deposited on polyethylene naphthalate flexible substrate by sputtering at room temperature. The electrical properties (such as carrier concentration, mobility, and resistivity) changed significantly with incorporation of Ag between the ITO layers. Comparison of sheet resistance of the IMI multilayers and the calculated sheet resistance of the Ag midlayer indicates that most of the conduction is through the Ag film. The critical thickness of Ag to form a continuous conducting layer is found to be 8 nm using electrical and optical analysis. A conduction mechanism is proposed to elucidate the mobility variation with increased Ag thickness. Carrier transport is limited by either interface scattering or grain-boundary scattering depending on the thickness of the Ag midlayer. Interface scattering is dominant for thinner (5.5–7 nm) Ag and grain-boundary ...

[1]  C. Guillén,et al.  ITO/metal/ITO multilayer structures based on Ag and Cu metal films for high-performance transparent electrodes , 2008 .

[2]  N. D. Theodore,et al.  Improved conductivity and mechanism of carrier transport in zinc oxide with embedded silver layer , 2008 .

[3]  C. Koo,et al.  ITO–Ag alloy–ITO film with stable and high conductivity depending on the control of atomically flat interface , 2007 .

[4]  M. Sinha,et al.  Effect of deposition process parameters on resistivity of metal and alloy films deposited using anodic vacuum arc technique , 2006 .

[5]  T. Alford,et al.  Band gap shift in the indium-tin-oxide films on polyethylene napthalate after thermal annealing in air , 2006 .

[6]  M. Kawamura,et al.  Sputter-deposition of Ag films in a nitrogen discharge , 2006 .

[7]  Terry Alford,et al.  Effect of various annealing environments on electrical and optical properties of indium tin oxide on polyethylene napthalate , 2006 .

[8]  Terry Alford,et al.  Characterization of the physical and electrical properties of Indium tin oxide on polyethylene napthalate , 2005 .

[9]  O. Park,et al.  Electron scattering mechanisms in indium-tin-oxide thin films: grain boundary and ionized impurity scattering , 2004 .

[10]  J. Bubendorff,et al.  Effect of substrate temperature on electrical, structural, optical and cathodoluminescent properties of In2O3-Sn thin films prepared by spray pyrolysis , 2004 .

[11]  H. Saka,et al.  Characteristics of Indium-Tin-Oxide/Silver/Indium-Tin-Oxide Sandwich Films and Their Application to Simple-Matrix Liquid-Crystal Displays , 2001 .

[12]  Young Ran Park,et al.  Large and abrupt optical band gap variation in In-doped ZnO , 2001 .

[13]  Xianghuai Liu,et al.  Intrinsic limit of electrical properties of transparent conductive oxide films , 2000 .

[14]  W. R. Salaneck,et al.  Kelvin probe and ultraviolet photoemission measurements of indium tin oxide work function: a comparison , 2000 .

[15]  Bruno K. Meyer,et al.  Dependence of the electrical and optical behaviour of ITO–silver–ITO multilayers on the silver properties , 2000 .

[16]  Alberto Piqué,et al.  Electrical, optical, and structural properties of indium–tin–oxide thin films for organic light-emitting devices , 1999 .

[17]  Gi-Seok Heo,et al.  TIZO/Ag/TIZO Multilayer Films for the Application of a Very Low Resistance Transparent Electrode , 1999 .

[18]  Josef Salbeck,et al.  Solid-state dye-sensitized mesoporous TiO2 solar cells with high photon-to-electron conversion efficiencies , 1998, Nature.

[19]  C. Daube,et al.  Dependence of oxygen flow on optical and electrical properties of DC-magnetron sputtered ITO films , 1998 .

[20]  Eli Harlev,et al.  A new method for the preparation of conductive polyaniline solutions : Application to liquid crystal devices , 1996 .

[21]  C. Granqvist,et al.  Solar energy materials , 1991 .

[22]  Lawrence R. Doolittle,et al.  Algorithms for the rapid simulation of Rutherford backscattering spectra , 1985 .

[23]  K. Chopra,et al.  Transparent conductors—A status review , 1983 .

[24]  A. P. Roth,et al.  Band-gap narrowing in heavily defect-doped ZnO , 1982 .

[25]  G. Haacke.  New figure of merit for transparent conductors , 1976 .

[26]  J. C. Phillips,et al.  Interband Transitions in Groups 4, 3-5, and 2-6 Semiconductors , 1962 .

[27]  Xiaofeng Xu,et al.  Properties of thin silver films with different thickness , 2009 .

[28]  Kazuhiko Seki,et al.  Dependence of indium–tin–oxide work function on surface cleaning method as studied by ultraviolet and x-ray photoemission spectroscopies , 2000 .

[29]  A. Heeger,et al.  Flexible light-emitting diodes made from soluble conducting polymers , 1992, Nature.