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Updated: May 2, 2026

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Dependency of the tunneling decay coefficient in molecular tunneling junctions on the topography of the bottom
1Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543 (Singapore) http://staff.science.nus.edu.sg/∼christiannijhuis/index.html; Graphene Research Centre, National University of Singapore, 6 Science Drive 2, Singapore, 117546 (Singapore).
Abstract:
A controversy in molecular electronics is the unexplained large spread in values of the tunneling decay coefficient β in tunneling junctions with self-assembled monolayers of n-alkanethiolates (SC(n)). We show control of the β value over the range 0.4-1.0 n(C)(-1) in junctions by changing the topography of the bottom electrodes that support the SAMs. Very low β values (0.4-0.5 n(C)(-1)) are obtained for rough surfaces with large areas of exposed grain boundaries, while β=1.0 n(C)(-1) for smooth surfaces with small areas of exposed grain boundaries.
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