Potentiality of polysilicon nanogap structure for label-free biomolecular detection

• Published in: Microelectronics international Vol. 30; no. 2; pp. 68 - 72
• Main Authors: Dhahi, T.S, Hashim, U, Ali, M.E
• Format: Journal Article
• Language: English
• Published: Bradford Emerald Group Publishing Limited 01.01.2013; MCB University Press
• Subjects: Acoustic wave devices, piezoelectric and piezoresistive devices; Applied sciences; Capacitance; Devices; Dielectrics; Electric currents; Electric fields; Electric power generation; Electrical engineering. Electrical power engineering; Electrodes; Electrolytes; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Etching; Exact sciences and technology; General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Microelectronics; Nanostructure; Phosphates; Physics; Power electronics, power supplies; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Sensing devices; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Silicon wafers; Studies; Double-layer capacitance; Dielectric-based biomolecular detection; Nanogap electrodes; Silicon; Sensors; Water; Phosphates; Measurement sensor; Polycrystal; Power electronics; Spacing; Buffer system; Electrolyte; Power device; Capacitance; Electric current measurement; Low-power electronics; Permittivity; Double layers; Cost lowering; Electrical characteristic; Dielectric devices; Damaging
• ISSN: 1356-5362; 1758-812X
• DOI: 10.1108/13565361311314449

Purpose - The purpose of this paper was to systematically study the electrical properties of 5-, 42- and 75-nm gap polysilicon structures to evaluate the potentiality of these structures to be used in biomolecular sensing devices.Design methodology approach - The authors previously reported the fabrication and morphological characterization of these structures. In this report, they electrically probed the presence of nanogap through current measurement. The effects of electrolytes on the capacitance profiles of these structures were systematically studied with air, water and various dilutions of phosphate buffer saline.Findings - An increment in capacitance was found with the increment in electrolyte concentration. Improvement in current flow, capacitance, permittivity, and conductivity were observed with the smaller size nanogaps, suggesting their applications in low power consuming devices.Originality value - Since nanogap-based dielectric biosensing devices need to be operated with a low level of current to avoid biomolecular damage, these structures should have potential applications in dielectric-based biomolecular detection using a low cost dielectric analyser.