Final Report : A Computational Investigation of Nanoelectromechnical Switches Report

The International Technology Roadmap for Semiconductors (ITRS) identifies emerging technologies with the potential to sustain Moore’s Law. A necessary succession from planar CMOS to non-planar/dual-gate CMOS, and ultimately to novel architectures such as carbon nanotube(CNT)-based nanoelectromechanical systems (NEMS) is envisioned. The ITRS also identifies critical roadblocks currently precluding advances beyond CMOS. Primary among the roadblocks to NEMS are poor reliability and manufacturing challenges. Here we investigate, both computationally and experimentally, the prevalent failure modes of CNT-based NEMS that hamper reliability. We first identify their point of onset within the design space, highlighting the extremely limited region in which failure is currently avoided. We use dynamic multiphysics models to elucidate the underlying causes of failure, and then show that the usable design space expands dramatically when employing novel electrode materials such as diamond-like carbon. We then demonstrate the efficacy of this solution through numerous successive actuation cycles without failure and applications to volatile memory operations. Finally, we develop a probe-based nanomanufacturing scheme by which to scale up manufacturing of these robust devices. Ultimately, these advances will be critical in delivering a broad class of robust, battle-ready NEMS sensors and electronics. (a) Papers published in peer-reviewed journals (N/A for none) O. Loh, X. Wei, C. Ke, J. Sullivan, and H.D. Espinosa "Robust Carbon-Nanotube-Based Nano-electromechanical Devices: Understanding and Eliminating Prevalent Failure Modes Using Alternative Electrode Materials" Small, Volume 7, No 1, p 79-86, 2011. R. Agrawal, O. Loh and H. D. Espinosa "The Evolving Role of Experimental Mechanics in 1-D Nanostructure-Based Device Development" Experimental Mechanics, Volume 51, Number 1, 1-9, DOI: 10.1007/s11340-010-9437-0 List of papers submitted or published that acknowledge ARO support during this reporting period. List the papers, including journal references, in the following categories: (b) Papers published in non-peer-reviewed journals or in conference proceedings (N/A for none) 2.00 Number of Papers published in peer-reviewed journals: Number of Papers published in non peer-reviewed journals: H. Espinosa, O. Loh, X. Wei. Robust Carbon Nanotube-Based NEMS: Understanding and Eliminating Prevalent Failure Modes Using Alternative Electrode Materials. Materials Research Society Fall Meeting, Boston, MA. November, 2010. O. Loh, X. Wei, K. Nandy, and H. Espinosa. Arrays of robust carbon nanotube-based NEMS: A combined experimental/computational investigation. Society for Experimental Mechanics Annual Conf. On Experimental and Applied Mechanics. Indianapolis, IN. June, 2010. O. Loh and H. D. Espinosa. Nanofountain probes for direct-write nanomanufacturing and in vitro single cell studies. IEEE Int’l. NanoElectroctronics Conference, Hong Kong, China. January, 2010. (c) Presentations 0.00 Number of Presentations: 3.00 Non Peer-Reviewed Conference Proceeding publications (other than abstracts): Number of Non Peer-Reviewed Conference Proceeding publications (other than abstracts): 0 Peer-Reviewed Conference Proceeding publications (other than abstracts): O. Loh, X. Wei, J. Sullivan, L. Ocola, R. Divan, H. Espinosa, "Robust carbon-carbon nanoelectromechanical switches," submitted. (d) Manuscripts Number of Peer-Reviewed Conference Proceeding publications (other than abstracts): 0 Number of Manuscripts: 1.00 Patents Submitted H. Espinosa, O. Loh, and X. Wei, "Electrodes to Improve Reliability of Nanoelectromechanical Systems," serial number 61/397,981