Synthesis and electrical characterization of ZnO and TiO2 thin films and their use as sensitive layer of pH field effect transistor sensors

ABSTRACTOxide thin films of zinc and titanium materials were deposited by different deposition techniques, to be applied as sensitive layers of pH sensor – EGFET device. The deposition techniques tested were dip-coat, spin-coat, electrodeposition and spray-pyrolysis. The routine and the parameters of each technique were changed aiming optimized the procedures. The pHs buffer solutions tested ranged from 2 to 12. ZnO thin film shows sensitivity about 23 mV/pH, while TiO2 thin films shows only 13.8 mV/pH. The final purpose of this study is to optimize the parameters for each deposition technique for both oxide materials.