WOLTE 2
Proceedings of the Second European Workshop on Low Temperature Electronics

J. Phys. IV France 06 (1996) C3-163-C3-167
DOI: 10.1051/jp4:1996325

Fabrication and Characterization of Single-Electron Transistors Based on Al/AlO_x/Al and Nb/AlO_x/Nb Tunnel Junctions

K. Blüthner¹, M. Götz¹, W. Krech¹, H. Mühlig¹, Th. Wagner¹, H.-J. Fuchs², D. Schelle², L. Fritzsch³, B. Nachtmann⁴ and A. Nowack<sup>4

1</sup>  Institut für Festkörperphysik der Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena, Germany
²  Institut für Angewandte Physik der Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena, Germany
³  Institut für Physikalische Hochtechnologie e.V. Jena, Helmholtzweg 4, 07743 Jena, Germany
⁴  II. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, 50937 Köln, Germany

Abstract
The SAIL (self-aligned in-line) technique has been applied to the preparation of ultrasmall metallic tunnel junctions. By using e-beam lithography and sputter methods the area of both Al/AlO_x/Al and Nb/AlO_x/Nb contacts has so far been reduced to less than 0.005µm². At low temperatures high-ohmic double junctions with a small metallic island in between show the Coulomb blockade effect. The current through such a device can be modulated by a voltage applied to a gate electrode capacitively coupled to the island (single-electron transistor). Both these single-charge phenomena have been observed at temperatures of a few hundred mK.

© EDP Sciences 1996