We make �molecular junctions� consisting of aromatic molecules covalently bonded to disordered graphitic carbon substrates and completed with a Cu or Au �top contact�.  Microfabricated molecular junctions range from 2.5 x 2.5 to 400 x 400 um in area, and can withstand temperature excursions from 5 K to >450 K without change in electronic behavior.  Current voltage cycles are reproducible with high yield >90 %, and may be scanned electronically for more than a billion cycles.  The electronic characteristics of the junctions depend strongly on the structure and thickness of the molecular layer, but are weakly dependent on temperature.  A detailed analysis of the conduction mechanism indicates hole tunneling through the molecular HOMO, and is governed by a modified Simmons relationship.  The results represent a significant step toward rational design of molecular electronic devices, and an understanding of the factors controlling electron transport through molecules.

Robust molecular tunnel junctions with high yield and temperature stability

243rd National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.