Colin Nuckolls, James Leighton and Latha Venkataraman, all of Columbia University, are funded by the Macromolecular, Supramolecular and Nanochemistry program in the Division of Chemistry for research to develop methods to design, create, and study single molecule chains and ribbons of silicon atoms. Pure silicon is, of course, widely used in the electronics and information technology industry and is highly valued for its properties as a semiconductor. Its semiconductor nature is the result of molecular and electronic properties that arise at the atomic level. Changes in silicon's electrical properties have been noted as the size of silicon-based devices, such as computer chips and information storage media, become smaller. The investigators are using precise molecular construction techniques to create highly electrically conductive forms of silicon with specific shapes and properties that have never before been studied. In particular, they are looking at tiny ribbons and wires of silicon that hold promise for the development of future electronic devices. This collaborative project is making an explicit connection between the properties of bulk silicon, the bedrock of information technology, and molecular forms of silicon, and is, thus, having a broad impact on the semiconductor industry. This project is having a further broad impact through a coordinated effort that spans K-8 outreach, curriculum development, and research training for undergraduate, graduate, and post-doctoral scientists.
The investigators are creating and studying atomically precise nanowires and nanoribbons of silicon that have been functionalized so they can be studied in unimolecular electrical devices. The design and synthesis of rigid, strained, and functional nanowires and nanoribbons of silicon is being used to test the impact of strain on single molecule conductance. Nanoscopic probes developed in this project are allowing the assembly and integration of these new nanomaterials into electrical devices. The combination of expertise among team members working in concert is allowing advanced molecules to be designed, synthesized, and studied in a feedback loop. This approach to research fosters a holistic understanding of these unique one-dimensional chains of silicon atoms and enhances the probability that new properties and devices will be discovered.