Comparison Between Performances of In ₂ O ₃ and In ₂ TiO ₅ -Based EIS Biosensors Using Post Plasma CF ₄ Treatment Applied in Glucose and Urea Sensing

In this study, the effect of post-deposition tetrafluoromethane (CF ₄ ) plasma treatment on the physical and electrical characteristics of an In ₂ TiO ₅ based electrolyte-insulator-semiconductor (EIS) sensor was investigated. Post-deposition CF ₄ plasma treatment typically improved the crystalline structure and repaired dangling bonds at the grain boundaries. We used the newly fabricated device to detect several ions, such as sodium and potassium, which are essential for many biological processes. The as-deposited and CF ₄ plasma treated In ₂ TiO ₅ sensing window with an EIS structure was also able to detect the pH of a solution, different alkali ions (Na ⁺ and K ⁺ ), glucose, and urea. The sensing membrane after a 60-sec CF ₄ plasma treatment displayed improved biosensing characteristics, such as higher sensitivity (59.64 mV/pH), better drift rate, and a smaller hysteresis voltage of approximately 0.424 mV/h. The In ₂ TiO ₅ sensing membrane treated with CF ₄ plasma is a promising material for use in EIS biosensing applications.