High sensing response of β-Ga2O3 thin film towards ammonia vapours: Influencing factors at room temperature

The gallium oxide (β-Ga2O3) thin films were deposited onto a quartz substrate using spray pyrolysis technique with gallium acetylacetonate as precursor salt. The X-ray diffraction pattern of the annealed film at 900 °C indicated the formation of monoclinic β-Ga2O3 phase with polycrystalline nature. Field emission scanning electron micrograph showed nanocrystallites over the film surface. The ammonia sensing property of the film at room temperature (∼30 °C) was studied by chemiresistive method. Influencing factors such as vapour concentration, relative humidity and film thickness in ammonia sensing performance were studied and reported.