Integrated of IDEs with TiO2 nanoparticles thin films for pH sensor

The combination of nano/micro technology, biology and metal oxides materials have seen great advances in the development of transducers and biochips for biological and medical fields. In this work, TiO2 nanoparticles thin films were prepared using sol-gel method and annealed at 400°C to promote nanoparticles crystallization in anatase phase. The influence of surface topologies and uniformity distribution of TiO2 thin films were investigated using AFM, whereby the surface structural was determined by XRD. The conventional photo-lithography technique was applied in the fabrication of micro-gap interdigitated electrodes (IDEs) with 7 μm gap size between the adjacent fingers. This device will be employed as an electrochemical sensor to detect the bio-molecules thru electrical characteristics. The fabricated micro-gap Au/Ti IDEs gap size was further inspected using the scanning electron microscopy (SEM). Purchased pH buffer solutions which varied from pH4 to pH 12 is dropped on the micro-gap IDEs and the effect on it is investigated for the application in pH measurement.