About the Seminar:
Traditional SEM-EDS analyses employ high acceleration voltages with 20 kV being the standard along with longer working distances; this limits the spatial resolution for EDS maps to around 30 to 50 nanometers and any further resolution improvements at those conditions demand considerable effort. Low voltage SEM-EDS analysis combined with a reduced working distance helps minimize the interaction volume and match the high resolution condition of the SEM. An alternative route to improve the spatial resolution of EDS maps entails using higher accelerating voltage in conjunction with an electron transparent sample with STEM-SEM. This presentation will review both low kV and 30 kV STEM-SEM modes for achieving high resolution EDS maps in an SEM with an emphasis on applications warranting such approaches. Further, the treatment will be extended to improving spatial resolution in EBSD analysis warranted for effective characterization of nanocrystalline materials as well as of heavily deformed samples.
About the Speaker
Dr. Sonika Robertson is a Territory Sales Manager Oxford Instruments NanoAnalysis supporting analytics for electron microscopes. She was awarded her B.S. and M.S. in Physics in 2010 from the University of Delhi and a Ph.D. in Mechanical Engineering from the University of Houston in 2018. Her doctoral research focused on mechanical and microstructural characterization of thermoelectric ceramics and reactively brazed metal-ceramic interfaces. Upon completion of her doctorate, she worked as a metallurgist and failure analysis engineer at Schlumberger investigating downhole tools from drilling, completions, and production & intervention, some of which involved losses of ~$1MM each incurred over a span of weeks to months and years. She then went on to manage the North America applications team for optical microscopy at Leica Microsystems before joining Oxford Instruments in 2022 and has over 15 years of hands-on experience in metallography and optical and electron microscopy.
