Nano-fabrication of molecular electronic junctions by targeted modification of metal-molecule bonds
2015 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, 14431Article in journal (Refereed) Published
Reproducibility, stability and the coupling between electrical and molecular properties are central challenges in the field of molecular electronics. The field not only needs devices that fulfill these criteria but they also need to be up-scalable to application size. In this work, few-molecule based electronics devices with reproducible electrical characteristics are demonstrated. Our previously reported 5 nm gold nanoparticles (AuNP) coated with omega-triphenylmethyl (trityl) protected 1,8-octanedithiol molecules are trapped in between sub-20 nm gap spacing gold nanoelectrodes forming AuNP-molecule network. When the trityl groups are removed, reproducible devices and stable Au-thiol junctions are established on both ends of the alkane segment. The resistance of more than 50 devices is reduced by orders of magnitude as well as a reduction of the spread in the resistance histogram is observed. By density functional theory calculations the orders of magnitude decrease in resistance can be explained and supported by TEM observations thus indicating that the resistance changes and strongly improved resistance spread are related to the establishment of reproducible and stable metal-molecule bonds. The same experimental sequence is carried out using 1,6-hexanedithiol functionalized AuNPs. The average resistances as a function of molecular length, demonstrated herein, are comparable to the one found in single molecule devices.
Place, publisher, year, edition, pages
2015. Vol. 5, 14431
Other Engineering and Technologies
IdentifiersURN: urn:nbn:se:uu:diva-264841DOI: 10.1038/srep14431ISI: 000361596000001PubMedID: 26395225OAI: oai:DiVA.org:uu-264841DiVA: diva2:861811
FunderSwedish Research CouncilKnut and Alice Wallenberg FoundationCarl Tryggers foundation Swedish Energy AgencySwedish Foundation for Strategic Research