Please visit http://chbe.gatech.edu/seminars to view seminar abstract.

January 11
Dr. Frances M. Ross
Manager, Nanoscale Materials Analysis Department
IBM's Watson Research Center
Vapour and Liquid Phase Crystal Growth In Situ in the Transmission Electron Microscope

Abstract
In situ transmission electron microscopy is a unique tool for visualizing and quantifying crystal growth. Processes such as physical vapour deposition, chemical vapour deposition and electrochemical growth can be carried out within the microscope, recording movies while growth takes place. From such movies we can measure kinetics, identify transient structures, and determine mechanisms. Here we will describe growth in two materials systems that illustrate the opportunities and challenges of the technique. In the vapour phase, we relate self-assembly of semiconductor nanostructures such as quantum dots and nanowires to strain, defect formation and step flow. In the liquid phase we describe electrochemical deposition of copper or zinc to form nuclei, thin films or dendrites, showing how the growth of individual structures as a function of electrochemical parameters allows diffusion processes to be characterized. The variety of materials and processes that can be examined suggest that in situ transmission electron microscopy of crystal growth can play a key role in developing future nanomaterials for areas as diverse as energy storage, microelectronics and photovoltaics.