Basic Research in Molecular Electronics: Toward Single Molecule Conductance Measurements
Gina M. Florio, Department of Chemistry, St. John's College of Liberal Arts and Sciences
The drive towards miniaturization of integrated circuits, coupled with fundamental limits in silicon-based technology, resulted in the development of the field of Molecular Electronics, a branch of Nanotechnology in which molecules are targeted as building blocks or individual components in electronic devices. The use of molecules in circuits is intriguing for a variety of reasons including their small size and the nearly endless ability to vary their structure, properties, and functions based on their chemistry. It is of both fundamental and practical importance to know the magnitude of the conductance (inverse of resistance) of individual molecules and the mechanism of charge transport if molecules are to be used as components in electronic circuits. To this end, we have built an instrument with the objectives of (a) accurately determining the single molecule conductance of a range of molecules, including well-designed model systems, (b) to investigate the mechanism of charge transport in each molecule, (c) to elaborate the role chemical functionality and molecular structure play in transport, (d) to study the effects of external factors such as tip-sample bias, gate voltage, and force on the conductance, and (e) to explore conductance as a function of metal-molecule linker chemistry. Initial results from our home-built instrument will be presented.