Thin films Titanium dioxide Extended gate field effect transistor (EGFET) Field effect transistors Oxide films pH effects pH sensors Sensing membranes Sol-gel spin coating Sol-gels Substrates Tin oxides pH Annealing Annealing condition Buffer solutions Coated glass substrates Constant temperature Deposition Deposition temperatures Dielectric layer Different substrates Drying Drying temperature Duration dependence EGFET Effect of annealing Electron beam lithography Electronic equipment Films properties