Piezo-tunnel effect in Al/Al2O3/Al junctions elaborated by atomic layer deposition
Abstract
In this work, the electrical transport in Al/Al2O3/Al junctions under mechanical stress is investigated in the perspective to use them as strain sensors. The metal/insulator/metal junctions are elaborated with a low temperature process (≤200 °C) fully compatible with CMOS back-end-of-line. The conduction mechanism in the structure is found to be Fowler-Nordheim tunneling, and efforts are made to extract the relevant physical parameters. Gauge factors up to -32.5 were found in the fabricated devices under tensile stress. Finally, theoretical mechanical considerations give strong evidence that strain sensitivity in Al/Al2O3/Al structures originates not only from geometrical deformations but also from the variation of interface barrier height and/or effective electronic mass in the tunneling oxide layer.
- Publication:
-
Journal of Applied Physics
- Pub Date:
- November 2017
- DOI:
- 10.1063/1.4994163
- Bibcode:
- 2017JAP...122r4501R