Metal-Molecule-Silicon Junctions Produced by Flip Chip Lamination of Dithiols: Effect of Molecular Length and Backbone

Abstract

The integration of organic molecules with silicon is increasingly being studied for potential as hybrid electronic devices. Creating dense and highly ordered organic monolayers on silicon with reliable metal contacts still remains a challenge. A novel technique, flip chip lamination (FCL), has been developed to create uniform metal-molecule-semiconductor junctions. FCL uses nanotransfer printing to covalently attach self-assembled monolayers to a hydrogen-passivated Si(111) surface. Several dithiol molecules were studied to explore the role of molecular length and chemical structure on the physical and electronic properties of the molecules. The effects of the FCL process on the chemical and physical properties of the imbedded molecular layer were interrogated with polarized-backside reflectance absorption infrared spectroscopy. Electrical measurements were also performed to characterize device structure and to offer better insight into the mechanisms at play in the electronic transport.