Nano Express

Nanoscale Research Letters

, Volume 2, Issue 2, pp 61-68

Open Access This content is freely available online to anyone, anywhere at any time.

Electrically tunable solid-state silicon nanopore ion filter

  • Julien VidalAffiliated withDepartment of Electrical and Computer Engineering, University of Illinois at Urbana-ChampaignBeckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign
  • , Maria E. GrachevaAffiliated withBeckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign
  • , Jean-Pierre LeburtonAffiliated withDepartment of Electrical and Computer Engineering, University of Illinois at Urbana-ChampaignBeckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign Email author 

Abstract

We show that a nanopore in a silicon membrane connected to a voltage source can be used as an electrically tunable ion filter. By applying a voltage between the heavily doped semiconductor and the electrolyte, it is possible to invert the ion population inside the nanopore and vary the conductance for both cations and anions in order to achieve selective conduction of ions even in the presence of significant surface charges in the membrane. Our model based on the solution of the Poisson equation and linear transport theory indicates that in narrow nanopores substantial gain can be achieved by controlling electrically the width of the charge double layer.

Keywords

Ion channels Artificial nanopore Silicon materials Nanofluidics