Featuring: Dr. Jennifer Cha
Department of Nanoengineering
University of California, San Diego
Despite the great potential of nanomaterials in electronic and photonic applications, their incorporation into functional devices will require the combination of top-down lithographic large-area patterning with the high resolution and chemical precision afforded by bottom-up self-assembly. To address some of the challenges, there have been significant efforts to use “bottom-up” or self-assembly approaches for patterning or organizing nanoscale materials. The first half of this talk will show our recent efforts in directing the placement of single stranded DNA and DNA templates on several different substrates that have been patterned by lithography. A variety of substrates have been generated by optical and e-beam lithography and these have been used to produce highly parallel arrays of meso- and macroscale DNA scaffolds and DNA oligonucleotides in a single step. Furthermore, these DNA templates encode multiple nanometer recognition sites that can be further used to generate hierarchical assemblies of both organic and inorganic nanoscale materials. For example, DNA arrays have recently been used to generate highly ordered, near-perfect metal nanocrystal superlattices at specific sites on a substrate through simple adsorption and annealing procedures that also demonstrate either hexagonal or cubic packing. In addition to the use of DNA interactions, the second half of the talk will highlight our research efforts in controlling interparticle associations by solvent or temperature to generate large area platelets of semiconductor nanorods in solution that can easily be deposited as an ink onto substrates to rapidly generate macroscopic arrays of normally oriented nanorods from the substrate.
Professor Cha has been an Assistant Professor in the Department of Nanoengineering at the University of California, San Diego since July 2008. Her research focuses on the design, synthesis, and integration of biomolecular materials for nanoscience. Specific research areas within her group include use of DNA nanomaterials for nanoelectronics, synthesis and engineering of smart biomolecular systems for sensing and medicine, and biochemical synthesis of inorganic nanomaterials for energy applications. Prior to this, Professor Cha was a research staff member at the IBM Almaden Research Center from 2004 to 2008, where she instigated a new program focused on bionanotechnology. She is the recipient of an IBM Innovation Research Award, a 2009 Hellman Faculty Award, 2009 DARPA Young Faculty Award, 2011 NSF CAREER Award, 2011 DOE Early Career Award and the 2011 Alfred P. Sloan Research Fellowship. Since joining UCSD, she has published over 40 publications in peer-reviewed journals and has given over 50 invited talks at numerous conferences, workshops, and universities.