We present complete experimental determinations of the tunnel barrier parameters (two barrier heights, junction area, dielectric constant, and extrinsic series resistance) as a function of temperature for the Ni-NiO-Ni system, showing that when the temperature-invariant parameters are forced to be consistent, good-quality fits are obtained between I-V curves and the Simmons equation for this very low-barrier system . A splitting of
meV in the barrier heights due to the different processing histories of the upper and lower electrodes is clearly shown. We present a fabrication technique that produces high yields and consistent junction behaviour. We present preliminary results of inelastic tunnelling spectroscopy at 4 K that show a prominent peak at ~59 meV, shifted with respect to the expected transverse optic phonon excitation in bulk NiO but consistent with other surface-sensitive experiments. We discuss the implications of these results for the design of efficient detectors for terahertz and infrared radiation.
By: Philip C. D. Hobbs; Robert B. Laibowitz; Frank R. Libsch
Published in: RC23493 in 2005
LIMITED DISTRIBUTION NOTICE:
This Research Report is available. This report has been submitted for publication outside of IBM and will probably be copyrighted if accepted for publication. It has been issued as a Research Report for early dissemination of its contents. In view of the transfer of copyright to the outside publisher, its distribution outside of IBM prior to publication should be limited to peer communications and specific requests. After outside publication, requests should be filled only by reprints or legally obtained copies of the article (e.g., payment of royalties). I have read and understand this notice and am a member of the scientific community outside or inside of IBM seeking a single copy only.
Questions about this service can be mailed to reports@us.ibm.com .