Titanium-doped indium oxide: A high-mobility transparent conductor

We report on the effects of titanium doping (0-7 at. %) on the optical and electrical properties of In2O3 using combinatorial deposition and analysis techniques. Maximum mobilities are observed at Ti concentrations of 1.5-2.5 at. % and are > 80 cm(2)/V s in sputtered films. The carrier concentration increased with titanium content to a high of 8.0 x 10(20) cm(-3). Data show that one carrier is generated per added Ti between 1 and 3 at. %. Conductivities up to 6260 Omega(-1) cm(-1) were observed. These remained very high > 5000 Omega(-1) cm(-1) across a wide compositional range. The optical transparency is high (> 85%) in a wide spectral range from 400 nm to at least 1750 nm. The work function of titanium-doped indium oxide varies substantially over the studied compositional range. (c) 2005 American Institute of Physics.