Heavy ions with kinetic energies in the MeV to GeV range offer unique possibilities of modifying materials properties and producing micro- or nano-structures. Each projectile creates a cylindrical track with a few nanometers in diameter, consisting of a zone of physically and chemically modified material [1]. This high local confinement in combination with large ranges (up to 100 µm and more) offers new perspectives to overcome limits of planar structuring techniques. To date, most of the applications are based on chemical track-etching, which dissolves the track material preferentially and creates fine channels of a few nanometers up to several micrometers in diameter. The superior properties of ion track membranes are related to the well-defined number, size, and shape of the pores. Various examples will be presented such as microfluidic systems with integrated nanoporous filter zones and perforated micromoulds [2]. Polymer foils containing single pores with a conical opening of a few nanometers exhibit extremely interesting ion-transport properties with possible application as sensors for biomolecules [3]. A large community utilizes ion-track membranes as templates for deposition of micro- and nano-wires of various materials [4]. References [1] e.g. proceedings of SHIM (Swift Heavy Ions in Matter) conferences, Nucl. Instr. and Meth. B 209 (2003). [2] S. Metz, C. Trautmann, A. Bertsch, and Ph. Renaud, J. Micromech. Microeng. 14 (2004) 324. [3] Z. Siwy, D. Dobrev, R. Neumann, C. Trautmann, K. Voss, Appl. Phys. A 76 (2003) 781. [4] M.E. Toimil Molares, E.M. Höhberger, Ch. Schaeflein, R.H. Blick, R. Neumann, C. Trautmann, Appl. Phys. Lett. 82 (2003) 2139.
Gesellschaft für Schwerionen, Planckstr. 1, 64291 Darmstadt, Germany