Development of nanogap based dielectric biosensor for label-free medical diagnostic analytical measurement

Abstract

Biosensor with electrode distances 75 nm and highly sensitive and selective is proposed in this research. The target application is the label-free detection of bio-molecular interaction for medical diagnostic analytical measurement. The fabrication process of the biosensor is based on conventional photolithography, e-beam evaporation and wet etching process. Sacrificial layer technique is applied in this research to form nanometer gap size between bottom and top electrode. Gold was chosen because of its properties that inert to atmosphere conditions and resistance to saline solution for bio-molecules immobilization and hybridization. For morphological and physical characterization, SEM, TEM and AFM are will be used while for electrical characterization, SPA and IV-CV system is used to determine the conductivity, capacitance and resistivity of the device. DNA is used as a sample for testing and the DNA extraction and preparation is done prior to immobilization and hybridization.