Improving the sensitive and selective of trace amount ozone sensor on Indium-Gallium-Zinc Oxide thin film by ultraviolet irradiation

Abstract In this study, we successfully developed amorphous Indium-Gallium-Zinc Oxide (IGZO) thin film under ultraviolet irradiation that demonstrated high stability and high sensitivity in a high-selectivity ozone gas sensor at ppb-level concentrations. The experimental results show that the sensor can detect ozone levels ranging from 55 to 400 ppb with high stability and high repeatability. We also successfully detected concentrations of 10–16 ppb. Ozone changes of 2–5 ppb can be clearly distinguished. Using electron spectroscopy for chemical analysis, we identified the element ratio and ozone detection ability. Higher sensitivity is realized in the presence of oxygen deficiency in metal oxide semiconductors. By controlling ultraviolet intensity, we found the sensitivity of thin film to ozone and nitrogen dioxide to be inversely proportional to light intensity and light intensity can be used to improve gas selectivity. Strong intensity irradiated to sensor causes low sensitivity and high selectivity.