Fabrication and characterization of polysilicon nanogap device for DNA hybridization detection

Abstract

Summary form only given. Fabrication and electrical characterization of 5-nm polysilicon gaps and their properties are discussed with their application in electrochemical sensors and biomolecule detection. To understand the relationship between the biosensor and nanotechnology we have carried out the fabrication and characterization of nanogap structures for DNA detection. In this paper, 2 mask designs are used. The first mask is for defining the lateral nanogap and the second mask is for the pad electrode pattern. Lateral nanogaps are formed using polysilicon and Au as the contact pad electrode. Conventional photolithography technique is used to fabricate the nanoogap structure. The electrical measurements are carried out using Dielectric Analyzer. The capacitance across the nanoogap was noted to change with probing and when target DNA solution is dropped between the gaps. The measured values of capacitance for the probe and target DNA solution are presented as a function of the frequency, where, the capacitance values were increased after immobilization of the target DNA and double increased after hybridization of the target DNA.