Strain sensing with submicron Al-AlO(x)-Al tunnel junctions.
We demonstrate a local strain sensing method for nanostructures based on metallic Al tunnel junctions with AlO(x) barriers. The junctions were fabricated on top of a thin silicon nitride membrane, which was actuated with an atomic force microscope tip attached to a stiff cantilever. A large relative change in the tunneling resistance in response to the applied strain (gauge factor) was observed up to a value of 37. This facilitates local static strain variation measurements down to approximately 10(-7). This type of strain sensor could have applications in nanoelectromechanical systems used in displacement, force, and mass sensing, for example.
Koppinen
P J
PJ
Department of Physics, Nanoscience Center, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland.
Lievonen
J T
JT
Ahlskog
M
M
Maasilta
I J
IJ