Analysis of Partial Hybridization and Probe Positioning on Sensitivity of a Dielectric Modulated Junctionless Label Free Biosensor

Abstract

The effect of partial hybridization and probe positioning on the performance of a label free biosensor has been investigated in this article. Dielectric modulated dual-metal double-gate oxide stacked junctionless MOSFET based biosensor device has been considered as a reference during analysis. Primarily, an optimized device dimension has been proposed based on device parameters, cavity positions, etc. Later, Sensitivity parameter variations in terms of threshold voltage (VTH) and drain current (IDS) have been investigated by considering partial hybridization (PH) and arrangement of receptor-biotarget pairs. Analytical modeling has been detailed to study the performance of the sensor. Extensive simulations using the SILVACO ATLAS investigate the effects. Mainly, irregular arrangements of biomolecules like an enzyme (Staphylococcal nuclease) and DNA (negatively-charged) are examined here. Also, the minimum detection limit of the biosensor has been addressed including a capacitive model. It was observed that the optimized cavity with dimension (400 nm × 10 nm) can accommodate almost 1.016 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> (~ 17 aM) number of Myoglobin enzyme. Analysis of these practical issues during the label free detection of charged/neutral biomolecules with higher sensitivity would be efficacious to find out the promising alternative in biosensing applications.