Nernst limit in dual-gated Si-nanowire FET sensors.
Field effect transistors (FETs) are widely used for the label-free detection of analytes in chemical and biological experiments. Here we demonstrate that the apparent sensitivity of a dual-gated silicon nanowire FET to pH can go beyond the Nernst limit of 60 mV/pH at room temperature. This result can be explained by a simple capacitance model including all gates. The consistent and reproducible results build to a great extent on the hysteresis- and leakage-free operation. The dual-gate approach can be used to enhance small signals that are typical for bio- and chemical sensing at the nanoscale.
Knopfmacher
O
O
Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland.
Tarasov
A
A
Fu
Wangyang
W
Wipf
M
M
Niesen
B
B
Calame
M
M
Schönenberger
C
C