Abstract
The electron-tunneling (ET) current through a barrier of thickness h is generally analyzed with the Simmons model, j ∼ exp(−βh), where β is the tunneling decay coefficient. We show that fluctuations in barrier thickness produce apparent β values systematically smaller than the real ones, which may lead to incorrectly postulating long-range electron tunneling. We reached this conclusion by performing the first tunneling studies through polyelectrolyte-multilayer films of different average thicknesses using impedance spectroscopy and EGaIn/Ga2O3 top contacts. We explained these measurements with a model that considers ET through a film with a Gaussian distribution of thicknesses, as observed by atomic force microscopy. It is shown that even relatively small thickness fluctuations can introduce a systematic error in the determination of β and that when the average film thickness and its standard deviation become commensurable, it is impossible to determine β.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.