AVS 47th International Symposium
    Electronics Tuesday Sessions
       Session EL+NS-TuM

Paper EL+NS-TuM5
Dissimilar Metal Electrodes with Nanometer Interelectrode Distance: Fabrication and Application to Characterizing Self-Assembled Molecular Electronic Devices

Tuesday, October 3, 2000, 9:40 am, Room 312

Session: Molecular Electronics
Presenter: M.A. Guillorn, University of Tennessee
Authors: M.A. Guillorn, University of Tennessee
I. Lee, University of Tennessee
D.W. Carr, Cornell Nanofabrication Facility
R. Tiberio, Cornell Nanofabrication Facility
E. Greenbaum, Oak Ridge National Laboratory
J. Lee, Oak Ridge National Laboratory
M.L. Simpson, Oak Ridge National Laboratory and The University of Tennessee
Correspondent: Click to Email
In order to advance the state of molecular-scale electronics research, electrode structures capable of realizing metal/molecular monolayer/metal heterojunctions have been fabricated using a variety of novel techniques that allow direct electrical contact with single molecules and small groups of molecules. By using Au as the electrode material, thiol-based self-assembly techniques have been successfully applied to deposit organic-synthetic molecules between these electrodes, thereby permitting their electrical characterization. This is possible due to the symmetry of these molecules. Unfortunately these techniques do not lend themselves to measuring the electrical properties of asymmetric molecules. An example of this type of molecule is the Photosystem I (PSI) reaction center which is of demonstrated interest to molecular-scale electronics research. Self-assembly techniques have been developed to preferentially orient the PSI with respect to a Au substrate, however, the polar nature of this molecule inhibits the use of this technique for the formation of Au/PSI/Au heterostructures. In this paper we will discuss a flexible and reproducible process for fabricating dissimilar metal electrodes with nanometer interelectrode distance (DiMEND) using high-resolution electron beam lithography and liftoff pattern transfer. This process is capable of realizing electrode pairs with a minimum interelectrode distance of less than 6 nm. This technique provides a reproducible method for creating lateral structures well suited for the electrical characterization of asymmetric molecules for molecular-scale electronics applications. Applications of this technology to characterizing self-assembled molecular electronic devices will be presented.