Nanowire reconfigurable FET as biosensor: Based on dielectric modulation approach. (November 2019)

• Record Type: Journal Article
• Authors: Saha, Priyanka; Kumar Dash, Dinesh; Kumar Sarkar, Subir
• Is Part Of: Solid-state electronics. Volume 161(2019)
• Publication Date: 2019-11
• Subjects: Reconfigurable FET -- Nanowire -- Biomolecules -- Metal S/D semiconductor junction -- Biosensor -- Threshold voltage -- Analytical model; Semiconductors -- Periodicals; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.sse.2019.107637
• Languages: English
• ISSNs: 0038-1101

Abstract

Highlights: Nanowire RFET as biosensor based on dielectric modulation approach is proposed. Analytical model of the structure is derived using proper boundary conditions. Variation in potential and Vth shift has been identified as detection metric. Characteristic trends of biosensor are studied thoroughly. Sensitivity is finally analyzed by assessing the threshold voltage variation. Abstract: In this paper, we have developed analytical surface potential and threshold voltage model of nanowire reconfigurable Field Effect Transistor (FET) which acts as a biosensor to detect the biomolecules, based on dielectric modulation approach. Due to its reconfigurable behavior, it acts as both p-type and n-type depending on the polarity of the biasing and hence find wide spread applications in the field of Programmable Logic Arrays (PLAs). The same is employed here as a bio sensor device with split gates and a cavity for biomolecules immobilization on a thin layer of silicon dioxide as adhesive layer. When the biosensor interacts with the bio targets of the cavity, the electrostatic properties of the device including variation in potential profile and threshold voltage shift get affected and thus have been identified as detection metric in this present work. The characteristic trends of the biosensor are studied with varying height, dielectric constant and charge of the bio-species as polarity of the applied biases change. In addition to this, sensitivity of nanowire RFET is analyzed by assessing the threshold voltage variation which is further compared with equivalent MOSFET biosensor. All the analytical results obtained are corroborated with technology computer-aided-design (TCAD) simulation data to verify the precision of our model.