pH sensing using in house fabricated polysilicon nanoelectrode based transducer

The biological and medical fields have taken the full advantage of nanotechnology in the development of transducers and biochips which are capable of characterizing bio-molecules. The research about the characterisation of nanoelectrode transducer using biomolecule detection technique has been studied to understand the important relationship between the transducer and the nanostructure which leads to high sensitivity and selectivity. We have applied conventional photolithography technique by using polysilicon on silicon substrate to fabricate a nanoelectrode transducer and employed as an electrochemical microelectrode sensors to measure the bio-molecules electrical characteristics. RIE and LPCVD processes were used during the transducer fabrication. Characterization is made both physically and electrically to check the surface topography and the electrical characteristics such as capacitance and conductance. Purchased pH buffer solutions which varied from pH1 to pH12 is dropped on the nanoelectrode and the effect on it is investigated for the application in pH measurement. This research has proven that increase in pH concentration is proportional with capacitance.