Nanotech 2010 Vol. 2
Nanotech 2010 Vol. 2
Nanotechnology 2010: Electronics, Devices, Fabrication, MEMS, Fluidics and Computational

MEMS & NEMS Devices Chapter 6

Nano-porous poly-silicon gated ion selective field effect transistors

Authors: N. Zehfroosh, M. Shahmohammdi, S. Mohajerzadeh

Affilation: University of Tehran, Iran, Islamic Republic of

Pages: 390 - 393

Keywords: ISFET, nanoporous, silicon, threshold voltage

Abstract:
We report the realization of ultra high sensitivity ion-selective field effect transistors (ISFET) devices by means of a nano-porous silicon structures placed on the gate region. Thanks to the presence of a nano-porous polysilicon film on the gate, the effective area of the exposed surface is numerously larger than that of the channel area. The response of such transistors to pH is essentially different from regular ISFETs where a change in threshold voltage is recorded. Depending on the measurement conditions and for a constant transistor current, a high shift in the drain-source voltage of the order of a few volts can be observed. A relative current-based sensitivity can be adopted for such devices. The proposed sensors show a superior sensitivity thanks to their 3-dimantional geometry.

Nano-porous poly-silicon gated ion selective field effect transistors

ISBN: 978-1-4398-3402-2
Pages: 862
Hardcopy: $189.95