Comparison of Sb₂O₃ and Sb₂O₃/SiO₂ Double Stacked pH Sensing Membrane Applied in Electrolyte-Insulator-Semiconductor Structure

In this study, electrolyte-insulator-semiconductor (EIS) capacitors with Sb₂O₃/SiO₂ double stacked sensing membranes were fabricated with pH sensing capability. The results indicate that Sb₂O₃/SiO₂ double stacked membranes with appropriate annealing had better material quality and sensing performance than Sb₂O₃ membranes did. To investigate the influence of double stack and annealing, multiple material characterizations and sensing measurements on membranes including of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) were conducted. These analyses indicate that double stack could enhance crystallization and grainization, which reinforced the surface sites on the membrane. Therefore, the sensing capability could be enhanced, Sb₂O₃/SiO₂-based with appropriate annealing show promises for future industrial ion sensing devices.