Influence of the air humidity on the electrical conductivity of the β-Ga2O3-GaS structure: air humidity sensor

The structural, morphological, and chemical properties of the beta-Ga2O3-GaS structure are investigated by means of X-ray diffraction technique, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. By selecting the annealing temperature and the duration of the annealing process, one can obtain the beta-Ga2O3 nanostructured compound, such as nanowires and nanoribbons, with thicknesses and surface areas required for certain types of electronic devices, in particular, for the gas and humidity sensors with various applications. Photosensitive wavelength range is from 200 to 320 nm. The results show that the photosensitivity and electrical conductivity of the n-type beta-gallium oxide nanostructured layers on a GaS substrate, such as the dependence of the current intensity in the circuit of beta-Ga2O3-GaS structure on the air relative humidity in the range from 42 to 92%, make this structure highly attractive for sensing applications. Reported data are important for the development of humidity sensors for harsh environments.