title: Effect of metal-molecule contact roughness on electronic transport: bacteriorhodopsin-based, metal-insulator-metal planar junctions.
abstract: Molecular electronics is very much about contacts, and thus understanding of any generic contact effect is essential to its advance. For example, it is still not obvious in how far variations in electrode roughness of macroscopic contacts can lead to rectification. Here we report an investigation of this contact effect on electronic transport properties using metal-insulator-metal planar junctions with a 5 nm thick bacteriorhodopsin-based insulator as model system. We demonstrate that the experimentally observed rectifying behavior is not an intrinsic property of the molecules used, but rather of the local contact quality. Even a slight increase in surface roughness of the bottom electrode gives rise to distinct rectifying behavior in these and, by extrapolation, possibly other molecular junctions.
authors.affiliation: Department of Organic Chemistry, Weizman Institute of Science, Rehovot 76100, Israel. ydjin1018@yahoo.com.cn
authors.forename: Yongdong
authors.initials: Y
authors.lastname: Jin
authors.forename: Noga
authors.initials: N
authors.lastname: Friedman
authors.forename: Mordechai
authors.initials: M
authors.lastname: Sheves
authors.forename: David
authors.initials: D
authors.lastname: Cahen
mesh_terms: D001436:Bacteriorhodopsins / Q000737:chemistry*; D001692:Biological Transport; D001703:Biophysics / Q000379:methods; D004553:Electric Conductivity; D004563:Electrochemistry / Q000379:methods; D004566:Electrodes; D004579:Electron Transport; D004581:Electronics; D008670:Metals / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D018717:Purple Membrane / Q000378:metabolism; D017655:Silicon Compounds / Q000737:chemistry; D055672:Static Electricity; D013997:Time Factors
chemical_list: D008670:Metals; D017655:Silicon Compounds; D001436:Bacteriorhodopsins; C032734:silicon nitride