On Wednesday, October 17, 2017, speaker Robert Sinclair will be discussing "In Situ High Resolution and Environmental Electron Microscopy Studies of Material Reactions." Mr. Sinclair is from the Department of Materials Science and Engineering at Stanford University. He is also the Director of the Wallenberg Research Link. This seminar will take place in the Cymer Conference Center (SME248).
Abstract:
There has been a steady growth in the applications and breadth of in situ transmission electron microscopy (TEM) since
the 1980’s [1]. At that time, the procedures to carry out meaningful experiments were described (e.g. [2]) but it was
thought that high voltage TEM and thick specimens were required to reproduce bulk behavior. However, in a series of
studies, we established that this was not necessarily the case and that high resolution TEM recordings could be made in
real time, in situ and that the atomic behavior associated with materials reactions at interfaces could be deduced (e.g.
[3],[4]). Moreover, with the advent of thin film and nanotechnology, the investigation of thin and nano-scale materials
became a necessity (e.g. [5]). In recent years, there has been an additional proliferation, most notably from in situ TEM in
controlled environments such as in gases and liquids (e.g. [1], [6]), and from the application of aberration-corrected TEM
(e.g. [7]).
This seminar gives a review of the application of in situ high resolution TEM to investigate material reactions, particularly
those associated with interfaces important in semiconductor processing. An overarching theme of our work has been to
ensure that the in situ studies are truly representative of the real behavior of the material system, and we have advanced a
number of guidelines to ensure this. Moreover, we have also expanded our approach to environmental material-gas
reactions such as carbon nanotube (CNT) oxidation [8], and the in situ study of CNT field emission for high intensity
X-ray sources [9]. The influence of the imaging electron beam is more important for the gaseous reactions, as it ionizes
the reacting gas species, and it is necessary to develop protocols to take this into account [10]. The procedures we have
adopted to do this will be carefully described [11].