Influence of Sb incorporation on optical, electrical and gas sensing properties of transparent ZnO thin films

• Transparent ZnO and ZnO:Sb thin films are deposited by vacuum evaporation followed by air annealing.
• Enhanced photoconductivity and transmittance are achieved on doping with Sb.
• Improved sensitivity and response time to Liquid Petroleum Gas on Sb doping of ZnO shows applicability in gas sensors.

Polycrystalline nanostructured thin films of n-type ZnO and Sb doped ZnO with doping at 1%, 3% &5% possessing tailored electrical and optical properties are prepared by vacuum evaporation followed by air annealing and their application as gas sensor is evaluated. Doped films show substantial improvement in response time and sensitivity to Liquid Petroleum Gas, with fastest response ∼20 s for 5% Sb doped samples. Doping enhances optical bandgap, transmittance, photoresponse and electrical conductivity. Carrier concentration and mobility are maximum for 5% doped, which corroborates the electrical conductivity variations for the doped samples which is also maximum for 5% doped.

(a)Transmittance curves of undoped and Sb doped ZnO thin films. (b) Photoresponse profile of undoped and Sb doped ZnO thin films (c) Gas sensitivity graph of undoped and Sb doped ZnO thin filmsFigure optionsDownload as PowerPoint slide