Annealing effects in tunnel junctions (thermal annealing)

This paper describes the results of subjecting Al-oxide-Pb tunnel junctions to thermal annealing. By looking at the junction resistance, barrier parameters (thickness, average barrier height, and the separation between the barrier heights at the Al and Pb electrodes), and inelastic electron tunneling (IET) peak intensities, one can study time-dependent effects occurring in the junction. These observations indicate changes in the tunneling barrier and IET spectra, and suggest that surface hydroxyl (-OH) groups experience reorientation.