“Seeing the Very Small:
Imaging and Solid-State Device Engineering at the Nanoscale”
Dr. Edward T. Yu, UT Austin
The science and engineering of materials and device structures at the nanometer scale have become central themes in fields ranging from solid-state electronics and photonics to the biological sciences. As a result, the characterization, understanding and control of material and device properties at the nanometer to atomic scale have emerged as essential aspects of materials and device engineering. We will discuss some recent results from our laboratory directed toward the imaging, analysis and application of nanoscale phenomena in a variety of solid-state materials and devices. In the area of nanoscale imaging and metrology, we show how scanned probe imaging of electronic structure in InGaN/GaN quantum-well heterostructures reveals nanoscale variations in carrier accumulation behavior associated with monolayer fluctuations in InGaN quantum well thickness, and how scanning capacitance imaging of ErAs semi-metallic nanoparticles embedded epitaxially in GaAs enables elucidation of nanoscale electronic structure, carrier modulation behavior and ErAs nanoparticle size distributions well below the typical resolution limit in proximal probe microscopy. In the area of high-efficiency photovoltaics we will discuss approaches for the design and fabrication of thin-film solar cells that exploit plasmonic effects and light scattering by metal and dielectric nanostructures integrated with the semiconductor device structure. We show that these approaches lead to substantial improvements in power conversion efficiency with the potential to enable realization of extremely thin, highly efficient solar cells and related devices.
Edward Yu received his PhD in applied physics from Caltech in 1991. Following a postdoctoral appointment at the IBM Thomas J. Watson Research Center he joined the electrical and computer engineering faculty at the University of California, San Diego. In 2009 he joined UT Austin, where he holds the Judson S. Swearingen Regents Chair in Engineering. He has been the recipient of an NSF CAREER Award, an ONR Young Investigator Award and an Alfred P. Sloan Research Fellowship, and he is an AVS fellow. Current research interests in his lab include photovoltaics and other technologies for energy generation; nanoscale imaging and characterization techniques; and solid-state nanoscience and nanotechnology generally. His research results have been reported in more than 140 archival journal publications.