Bio

Farnaz Niroui is currently a Ph.D. candidate in the Department of Electrical Engineering and Computer Science at Massachusetts Institute of Technology. She is a recipient of the Natural Sciences and Engineering Research Council of Canada Scholarship for graduate studies. Farnaz received her Master of Science degree in Electrical Engineering from MIT in 2013, working with Professors Vladimir Bulovic and Jeffrey Lang. She completed her undergraduate studies in Nanotechnology Engineering at University of Waterloo in Canada. Her research interest is at the interface of device physics, materials science and nanofabrication to enable study, manipulation and engineering of systems with unique functionalities at the nanoscale.

Nanoscale Engineering with Molecular Building Blocks

Nanoscale Engineering with Molecular Building Blocks

Mechanical properties of materials at the nanoscale can lead to unique physical phenomena and devices with improved performance and novel functionalities. My research utilizes the mechanical behavior and structural deformations of few-nanometer-thin molecular films to achieve precise nanoscale force control. This combined with deformation-dependent changes in the electrical and optical properties of matter creates a platform enabling development of novel device concepts. Based on these principles, I have developed electromechanically tunable nanogaps composed of self-assembled compressive organic films sandwiched between conductive contacts. An applied voltage across these electrodes provides an electrostatic force that causes mechanical compression of the molecular layer to modulate the gap size. Through modifying the molecular film by chemical synthesis and thin-film engineering, the nanogap dimensions and the extent of compression can be precisely controlled. The compressed molecules also provide the elastic force necessary to control the surface adhesive forces to avoid permanent adhesion of the electrodes (defined as stiction) as the gap is mechanically tuned. Utilizing these nanogaps, I have designed nanoelectromechanical (NEM) switches that operate through a tunneling switching mechanism. In this scheme, the electrostatic compression of the molecules leads to a decrease in the tunneling gap and an exponential increase in the tunneling current. With sub-5 nm switching gaps and nanoscale force control, these low-voltage and stiction-free devices overcome the challenges faced by the current contact-based NEM switches giving rise to promising applications in low-power electronics. Beyond electromechanical switches, these mechanically active nanogaps exhibit applications as molecular metrological tools for probing nanoscale mechanical and electrical properties, and can enable dynamically tunable optical and plasmonic systems.