Unraveling the impact of nano-scaling on silicon field-effect transistors for the detection of single-molecules

Abstract

Electrolyte-gated silicon field-effect transistors (FETs) capable of detecting single molecules could enable high-throughput molecular sensing chips to advance, for example, genomics or proteomics.

(Invited) BioFETs and Nanopore FETs: Nanoscale Silicon Field-Effect Transistors for Single-Molecule Sensing

“…To realize single-molecule sensing the single-molecule signal-to-noise ratio (SNR) must be sufficiently high. Downscaling the device area is key to increase SNR (∝ 1/√area) (11,12), see figure 1. Although many reported FET sensors have nanoscale crosssections, their gate lengths are typically micron-scale (1-5).…”

“…Although many reported FET sensors have nanoscale crosssections, their gate lengths are typically micron-scale (1-5). Our FET modeling work (12) shows that a sufficiently large single-molecule Signal-to-Noise Ratio (SNR) can be obtained when also downscaling the silicon FET gate length. The downscaling of the FET is essential as well to achieve an unprecedented sensor density and consequently read throughput.…”

“…Our detailed TCAD-based FET modeling work (12) shows that a sufficiently large single-molecule Signal-to-Noise Ratio (SNR) can be obtained when nano-scaling all FET channel dimensions (12). For solid-gated silicon FETs it is well-known that nano-scaled devices are sensitive to single elementary charges near the silicon-oxide interface, which gives rise to so-called Random Telegraph Noise (RTN).…”

“…In (12) we enhanced a Technology Computer-Aided Design (TCAD) tool with electrolyte screening models to calculate the impact of the FET geometry on the singlemolecule signal and FET noise. Our continuum FET model shows that a sufficiently large single-molecule SNR is only obtained when nano-scaling all FET channel dimensions.…”

Tuning conductivity while maintaining mechanical properties in perylene bisimide hydrogels at physiological pH

“…1,[4][5][6][7] For example, when growing nerve cells, an appropriate mechanical stiffness is required and an electric field is desired. 8,9 There are many options for achieving conductive materials from the assembly of low-molecular-weight gelators that can be functionalised for specific applications. [10][11][12] The problem lies in the method of gelation, as gelation triggers being often unsuitable for biological applications or resulting in gels with unsuitable properties for physiological conditions.…”