Investigations on high visible to near infrared transparent and high mobility Mo doped In2O3 thin films prepared by spray pyrolysis technique

High visible to near infrared (NIR) transparent Mo (0-1 at%) doped In2O3 (IMO) thin films with high carrier mobility were deposited on Corning-1737 glass substrates at 400 degrees C by spray pyrolysis experimental technique. The films were annealed in vacuum (similar to 1 x 10(-4) mbar) at 550 degrees C for 45 min. XRD analysis confirmed that indium oxide belongs to cubic bixbyite structure. The preferred growth orientation along (2 2 2) plane for low Mo doping level shifts to (4 0 0) for higher Mo doping levels. Crystallite sizes extracted from the XRD data corroborate the changes in full-width at half-maximum due to the variation in Mo doping. Scanning electron microscopy study illustrates the evolution in surface microstructures as a function of Mo doping. The negative sign of Hall coefficient confirmed n-type conductivity. Films with high mobility of similar to 149 cm(2)/(V s), carrier concentration of similar to 1.0 x 10(20) cm(-3), resistivity of similar to 4.0 x 10(-4) Omega cm and high figure of merit of similar to 1.02 x 10(-2) Omega(-1) were observed for post-annealed films (0.5 at% Mo). The obtained high average transparency of similar to 83% in the wavelength range 400-2500 nm confirms that transmittance is well extended into the NIR region. (C) 2009 Elsevier B.V. All rights reserved.