Fan05 - 07(2005 PHYSICAL REVIEW LETTERS week ending 19...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Polarity Switching and Transient Responses in Single Nanotube Nanofuidic Transistors Rong Fan, 1 Min Yue, 2 Rohit Karnik, 2 Arun Majumdar, 2,3 and Peidong Yang 1,3, * 1 Department of Chemistry, University of California, Berkeley, California 94720, USA 2 Department of Mechanical Engineering, University of California, Berkeley, California 94720, USA 3 Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA (Received 1 May 2005; published 19 August 2005) We report the integration of inorganic nanotubes into metal-oxide-solution ±eld effect transistors (FETs) which exhibit rapid ±eld effect modulation of ionic conductance. Surface functionalization, analogous to doping in semiconductors, can switch the nano²uidic transistors from p - type to ambipolar and n - type ±eld effect transistors. Transient study reveals the kinetics of ±eld effect modulation is controlled by ion-exchange step. Nano²uidic FETs have potential implications in subfemtoliter analytical technology and large-scale nano²uidic integration. DOI: 10.1103/PhysRevLett.95.086607 PACS numbers: 85.30.Tv, 66.10.Ed, 82.65.+r The ability to manipulate charge carriers (electrons and holes) in metal-oxide-semiconductor ±eld effect transistors (MOSFETs) has revolutionized how information is pro- cessed and stored, and created the modern digital age. Analogous to MOSFETs, introducing ±eld effect modula- tion in micro or nano²uidic systems in a three-terminal device would enable the manipulation of ionic and mo- lecular species at a similar level and even logic operation. Because of strong Debye screening in aqueous solutions [1], ±eld effect modulation of ion transport arises only in systems whose dimensions are comparable to the critical Debye Length, i.e., nano²uidic channels [2]. Nano²uidics has already attracted remarkable attention for ultrasensitive or even single molecule level detection and biological activity study [3]. For instance, membrane channel proteins and arti±cial solid state nanopores were utilized for single molecule sensing, con±guration study, and DNA sequencing [4,5]. These nanochannel/nanopore devices usually passively transport ionic species, similar to electrical resistors. Analogous to unipolar MOSFETs, in- troducing external electrical ±eld to modulate ionic con- ductivity would promote nano²uidics to a higher level of controllability or even logic. It is also notable that the single conical nanopore has been reported to exhibit active recti±ed ion transport in a two-terminal device con±gura- tion [6]. Single nanochannel studies have shown that the surface charge governs the ionic transport and induces the formation of unipolar solutions as in unipolar MOSFETs [7,8]. Metal nanotubule membranes exhibited selective ion ²ux upon electrochemically tuning surface charges [9].
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This document was uploaded on 08/16/2010.

Page1 / 4

Fan05 - 07(2005 PHYSICAL REVIEW LETTERS week ending 19...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online