Two-dimensional MoS_2 negative capacitor transistors for enhanced (super-Nernstian) signal-to-noise performance of next-generation nano biosensors

摘要

The detection of biomolecules by a Field Effect Transistor-based biosensor (BioFET) is dictated by the sensor's intrinsic Signal-to-Noise Ratio (SNR). The detection limit of a traditional BioFET is fundamentally limited by biomolecule diffusion, charge screening, linear charge to surface-potential transduction, and Flicker noise. In this letter, we show that the recently introduced class of transistors called negative capacitor field effect transistors offers nonlinear charge transduction and suppression of Flicker noise to dramatically improve the SNR over classical Boltzmann sensors. We quantify the SNR improvement (approximately two orders of magnitude higher than a classical Si-nanowire biosensor) by interpreting the experimental results associated with the signal and noise characteristics of 2D MoS2-based transistors. The proposed Negative Capacitor BioFET (NC-BioFET) will motivate experimentalists to combine two well-established technologies to achieve high SNR (and to improve the detection limit), fundamentally unachievable by any other sensor technology.