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Both gamma radiation and ozone sensing properties of mixed oxides in the form of thin films are explored. External effects, such as radiation and ozone, cause defects in the materials it interacts with and, consequently, it causes changes in their properties. These changes manifest themselves as the alterations in both the electrical and the optical parameters, which are being measured and employed for dosimetry sensor development. An Edwards E306A thermal coating system was used for In 2 O 3 :ZnO:SnO 2 (90%:5%:5%) films deposition. For the electrical properties measurements, Cu electrodes were manufactured on the glass substrate via thermal evaporation of Cu; then AZ5214 photoresist was spin-coated over it and exposed to ultraviolet (UV) light via the acetate, containing the desired electrodes patterns. After the exposure, the substrate was placed in Electrolube PDN250ML developer solution and then rinsed in water and placed in the etching solution of SEMO 3207 fine etch crystals to reveal the electrode pattern. The optical properties of In 2 O 3 :ZnO:SnO 2 thin films were explored using CARY 1E UV-visible spectrophotometer. The values of the optical band gap E opt are estimated in the view of the Mott and Davis' theory. Doping of In 2 O 3 with 5% ZnO and 5% SnO 2 dramatically changes the overall structure of the film and thus affects its sensing to gamma radiation and ozone.Mixing metal oxides in certain proportions provides a tool for controlling the sensors response.

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Ozone sensing properties of mixed oxides of In 2 O 3, ZnO , and SnO 2 in the form of thin films are explored. Exposure to ozone causes defects in the materials, and subsequently causes changes in the materials properties. In this work, a cost-effective, room temperature, real-time ozone monitoring device has been developed. The fabricated sensors are capable of detecting threshold ozone safety levels proposed by the World Health Organization (WHO) while operating at room temperature. Room temperature operation offers many advantages over high temperature operation, such as reduced power consumption, reduced fabrication costs, and ease of implementation into portable devices, such as laptops and mobile phones. The fabrication of these sensors was carried out by means of an Edwards E306A Coating System. Various mixtures of In 2 O 3, ZnO , and snO 2 were deposited in a rectangular pattern on top of copper interdigitated electrodes. X-ray Photo Spectroscopy (XPS) analysis showed that there were levels of impurities in the sensor samples, which were dependant on the fabrication process and parameters. XPS analysis also gave a detailed account of the shifts in binding energies of the thin oxide layers. The results presented show that the highest response to environmentally relevant ozone concentrations is achieved with a very thin sensing layer and a high deposition rate. The performance of the sensors has been investigated and compared.

This work investigates the ozone sensing properties of NbO 2 thin films operating at room temperature. NbO 2 thin films have been deposited on alumina and glass substrates provide with Cu interdigitated electrodes by the Vacuum Thermal Evaporation technique. The optical properties of NbO 2 thin films were explored using CARY 1E UV-Visible Spectrophotometer. The values of the optical band gap E OPT are estimated in view of the Mott and Davis' theory. The electrical response has been measured by exposing the sensing layers to ozone (ppb). NbO 2 films fabricated by this method have shown good sensitivity to envinronmentally relevant ozone concentrations.