Biochemical Sensors: Comparison of the Performance of TiO₂, SnO₂:F and ITO Used as the Main Sensing Element

Abstract

Development of new biosensors has extremely importance in medicine. The main targets are the miniaturization of these devices, less invasive methods to the patient, high sensitivity and fast response. The deposition method to produce the oxide thin films has great influence on films properties, to be used as sensitivity layer of a biosensor. Several oxide materials have been developed to find the higher sensitivity, close to Nernst equation and fast response. Titanium oxide, fluorine-doped tin oxide and indium tin oxide are compared using different deposition techniques. The higher sensitivity was reached using fluorine-doped tin oxide prepared by chemical vapor deposition (about 58 mV/pH).

ZnO thin films applied as pH sensor in EGFET devices

“…In medical fields, the pH detection plays an important rule, as well as industrial fields. With that, the development of alternative electrodes such as pH sensor based on field effect transistors, or solid-state, brings huge advantages [4].…”