We constructed a pair of parallel conducting metal (Ag) plates separated by patterned molecular monolayers at the corners of the plates. A special metal deposition process was developed to ensure atomic scale flatness in the conducting plates. The separation between the plates can be controllably varied between several angstroms and tens of nanometers by varying the length of the molecules and/or employing conventional substrate processing techniques. The structure is an efficient sensor for detecting single molecules via surface enhanced Raman spectroscopy (SERS). The unique configuration of the plates also allows for investigation of Casimir force between two parallel plates and helps in elucidating some of the unexplained observations in molecular electronic junctions.
Project end date: 08/11/08