Effect of nanowire number, diameter, and doping density on nano-FET biosensor sensitivity (original) (raw)

Toronto ON M5S 3G8, Canada^These authors contributed equally to this work. N anowire field-effect transistors (nano-FETs) enable dynamic label-free detection of molecules with higher sensitivity and shorter detection times compared to conventional bioassays. Research efforts over the past decade have produced significant advances in nano-FET biosensor technology and resulted in highly sensitive proofof-concept devices capable of detecting exceedingly low concentrations of proteins, 1À3 nucleic acids, 4,5 and viruses 6 in solution. In order to achieve high performance and consistency across devices, understanding sensing mechanisms and the effect of important parameters is important. A number of experimental studies have been reported, which sought to elucidate the sensing mechanism and the effect of various device parameters on nano-FET sensitivity including electrode material, 7 nanowire composition, 8,9 functionalization method, receptor size, 10,11 gate bias, 12À14 electrolyte ion concentration, 15,16 and analyte delivery methods. 17À19 However, the influence of nanowire number, doping density, and diameter on nano-FET biosensor sensitivity remains to be experimentally quantified.