Ozone and gamma radiation sensing properties of In2O3:ZnO:SnO2 thin films

Abstract

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.

In2O3- and SnO2-Based Thin Film Ozone Sensors: Fundamentals

“…General descriptions of conductometric gas sensor fabrication and operation can be found in review papers [18,[24][25][26][27][28][29][30][31][32]. As shown in Table 2, at present, many materials [15,[32][33][34][35][36][37][38][39][40][41] have been tested for the design of conductometric ozone sensors, and many various technologies, such as solgel [42], laser ablation [35], sputtering [38], spray pyrolysis [43][44][45], RGTO [46], successive ionic layer deposition [47], vacuum evaporation [48], and solvothermal synthesis [49], have been applied for preparing gas-sensing layers based on these materials. Comparative evaluation of developed conductometric ozone sensors based on various metal oxides is shown in Table 3.…”

Ultraviolet radiation sensing in composite oxide semiconductor films

“…2 Indium zinc oxide ͑ISZ͒ is one of these new materials, and it can be used not only as a substitute of conventional transparent conductive oxides but also as a potential material for ␥-radiation sensing. 4 In this letter, we report that the ISZ films synthe-sized by the pulsed-laser deposition ͑PLD͒ system demonstrate potential candidate for UV sensor.…”

Analysis of the Sensing Properties of a Highly Stable and Reproducible Ozone Gas Sensor Based on Amorphous In-Ga-Zn-O Thin Film

“…To clearly observe the R - T curves, the time axis was shifted for the samples with 0.5–4-ppm exposure [4,22,23,24,25,26,27]. …”