Figure 1.

(a) Illustration of the biologically active field-effect sensing principle for a p-type SiNW FET (cross-sectional view). SiNWs are connected to source (S) and drain (D) electrodes and are biofunctionalized with molecular probes. A front gate electrode is used to modulate the NWs’ conductivity. Specific binding of negatively charged target bioanalytes onto the probes will result in accumulation of positive carriers at the SiNW surface, leading to detectable increases in conductivity. (b) Image of an integrated SiNW FET biosensor with implemented poly-SiNW sensing block, microcontroller, temperature sensor, analog-to-digital converter and wireless transceiver. Reprinted with permission from Ref. [21], Copyright (2014), Elsevier. (c) Chronological development procedure of a SiNW FET device for molecular sensing application from design, device fabrication, on-chip packaging and molecular probe functionalization.