Energy and electronic nanomaterials and interfaces: Directed synthesis, assembly and modification of nanostructures
Professor Ramanath received his Ph.D. in Materials Science and Engineering from the University of Illinois-Urbana in 1997. His doctoral work won him a Materials Research Society Graduate Student Award (now known as the Gold Award). He obtained his B. Tech. in Metallurgical Engineering from the IIT, Madras, India, and his M.S. in Materials Science and Engineering from the University of Cincinnati. He was a staff member at Novellus Systems, CA, and a Visiting Scientist at the Physics Department of Linköping University, Sweden, before he joined the Rensselaer faculty in Fall 1998 as an Assistant Professor. He became a tenured Associate Professor in 2003, and was promoted to full Professor in 2006. He served as the Director of the New York State Center for Future Energy Systems (4/08-1/10). He is a recipient of a Early CAREER Award from the National Science Foundation (2000), Prof. Bergmann Memorial Young Scientist Award from the US-Israel Binational Science Foundation (2003), and is a co-recipient of IBM Research Partnership Award (1999-2006), Best paper award IEEE Nano (Hong Kong, 2007). He has been a Visiting Professor at the International Center for Young Scientists (ICYS, 2004) and the World Premier Institute for Materials Nanoarchitectronics (MANA, 2010) at the National Institute of Materials Science, Tsukuba, Japan, the Nanoscale Science Department at the Max Planck Institute für Festkörperforschung, Stuttgart, Germany as an Alexander von Humboldt Fellow (2004-2005), and the Indian Institute of Science, Bangalore, India (2006), and the University of Wollongong, Australia (2007-2010). He is an Associate Editor of IEEE Transactions on Nanotechnology since 2003, and serves on the editorial advisory board of the Journal of Experimental Nanoscience and the The Open Materials Science Journal.
Professor Ramanath's current research interests are in the areas of nanostructured materials and interfaces for materials discovery and design for applications in energy, electronics and heat management. Directed synthesis, assembly, modification and scalable processing. Atomic-/molecular-level understanding and engineering of structural and functional properties and stability of nanoscopic building blocks, their architectures and assemblies, and their interfaces. Synergystically combining multiple microscopy and spectroscopy techniques (e.g., TEM, SEM, diffraction, RBS, XPS, XANES, AES, SIMS, EDX) together with device fabrication and testing to capture and manipulate key atomistic/molecular/electronic structure-level phenomena for applications. Below are synopses of current topics being pursued in his group.
Nanoscopic building blocks and heterostructures: Directed synthesis, assembly and properties
Advanced Materials 2008, Nano Lett 2010, ACS Nano 2010, J Phys Chem C 2010...
Devise strategies to synthesize and assemble nanostructures of desired size, shape, stability and properties, and by combining chemical and/or physical guidance (e.g., molecularly-directed nanostructure sizing, shaping and doping; lithography, ion irradiation, microwave stimulation) with self-assembly and scalable non-vacuum processing. Understand and manipulate molecular/atomic-level mechanisms and relationships between processing parameters, nanostructure and assembly structure and chemistry, to tailor functional (thermal, mechanical and electronic) properties. Examples of structures being investigated include nanowires, nanorods, nanoplates, and their thin fiml and bulk assemblies, core-shell and branched structures, interpenetrating nanowire networks of high- and low-bandgap seminconductors.
Present projects: Nanostructured bulk high figure of merit thermoelectric materials, nanotube/nanowire/nanoparticle networks and composites for photovoltaics and heat management devices.
Molecularly tailored interfaces: understanding and manipulating nanoscale phenomena for enhanced properties
Nature 2007, ACS Applied Materials and Interfaces 2010, Phys. Rev. B 2011...
Investigate and develop the use of molecular nanolayers to tailor the mechanical integrity, chemical stability, and electrical and thermal transport properties of hard-soft and hard-hard interfaces, nanostructures and their assemblies for applications in nanoelectronics, porous materials and thin films and bulk nano-/bio-composites. Enable the direct integration of non-sticking metallic and dielectric materials. Directly access and tune nanoscale phenomena and properties (e.g., Fermi-level pinning, interfacial thermal conductance, charge capacity) and develop atomistic/molecular-level understanding of interface stability-property relationships.
Present projects: Nanomechanics of interfacial fracture and corrosion at molecularly tailored interfaces, work function tuning at metal/high-k interfaces, thermal conductance manipulation for heat management, molecularly functionalized low-k and high-k dielectrics and nanoelectrodes for nanodevice wiring and energy storage.
Processing and microanalytical techniques
We are interested in, and adept at, synergistically combining and devising new multiple processing approaches for thin film/nanostructure synthesis, and exploiting multiple microanalysis techniques to capture key features of atomistic/molecular-level phenomena. We use combinations of CVD, PVD, directed self-assembly (from wet-chemical and vapor-phase fluxes), nanofabrication (e.g., lithography, etching), ion-irradiation, microwaves, and post-deposition annealing in vacuum/controlled gas ambients. We are particularly interested in low-energy intensity and scalable techniques. Our growing toolbox of microanalytical techniques include electron microscopy (conventional and high resolution TEM, diffraction, SEM), related spatially resolved X-ray and electron spectroscopy techniques, XRD, various spectroscopies (e.g., RBS, XPS, AES, SIMS, EDX, IR, UV-visible), in situ electrical measurements during deposition and annealing, four-point bend adhesion testing and electrical device testing (I-V, C-V, TVS, etc.).