title: Dependency of the tunneling decay coefficient in molecular tunneling junctions on the topography of the bottom electrodes.
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.
authors.affiliation: Department 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).
authors.forename: Li
authors.initials: L
authors.lastname: Yuan
authors.forename: Li
authors.initials: L
authors.lastname: Jiang
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Christian A
authors.initials: CA
authors.lastname: Nijhuis
keywords: bottom electrodes; charge transport; molecular electronics; self-assembled monolayers; tunneling decay constant