Ultrahigh-Density Nanowire Arrays Grown in Self-Assembled Diblock Copolymer Templates

American Association for the Advancement of Science (AAAS) - Tập 290 Số 5499 - Trang 2126-2129 - 2000
Thomas Thurn‐Albrecht1, J. Schotter2, G. Kästle2, N. C. Emley2, T. Shibauchi3,4, L. Krusin‐Elbaum3, K.W. Guarini3, Charles T. Black3, Mark Tuominen2, Thomas P. Russell1
1Polymer Science and Engineering Department,
2Physics Department, University of Massachusetts, Amherst, MA 01003 USA
3IBM T.J. Watson Research Center, Yorktown Heights, NY 10598, USA;
4Los Alamos National Laboratory, Los Alamos, NM 87545, USA

Tóm tắt

We show a simple, robust, chemical route to the fabrication of ultrahigh-density arrays of nanopores with high aspect ratios using the equilibrium self-assembled morphology of asymmetric diblock copolymers. The dimensions and lateral density of the array are determined by segmental interactions and the copolymer molecular weight. Through direct current electrodeposition, we fabricated vertical arrays of nanowires with densities in excess of 1.9 × 10 11 wires per square centimeter. We found markedly enhanced coercivities with ferromagnetic cobalt nanowires that point toward a route to ultrahigh-density storage media. The copolymer approach described is practical, parallel, compatible with current lithographic processes, and amenable to multilayered device fabrication.

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American Association for the Advancement of Science (AAAS)

Tập 290 Số 5499

2126-2129

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