AVS 58th Annual International Symposium and Exhibition
    In Situ Spectroscopy and Microscopy Focus Topic Monday Sessions
       Session IS+AS+SS-MoA

Invited Paper IS+AS+SS-MoA1
A New Approach to Defect Evolution Studies – Combined In Situ Experiments and Electron Tomography

Monday, October 31, 2011, 2:00 pm, Room 106

Session: In Situ Characterization of Solids: Film Growth, Defects, and Interfaces
Presenter: Ian Robertson, University of Illinois at Urbana-Champaign
Authors: I.M. Robertson, University of Illinois at Urbana-Champaign
J. Kacher, University of Illinois at Urbana-Champaign
G. Liu, University of Illinois at Urbana-Champaign
Correspondent: Click to Email
Electron micrographs are two-dimensional images capturing specific instances in the evolution of the microstructure and composition as well as the electronic and magnetic state. As these yields no insight as to how the state evolved, a posteriori knowledge is used to determine the most likely pathway. This challenge can be addressed by conducting experiments in situ in the transmission electron microscope, which allows direct observation and in some cases quantification of the reactions and interactions responsible for the evolved structure. The information, however, remains two-dimensional and with increasing use of this technique it is becoming apparent that lack of three-dimensional knowledge is hindering interpretation. Information in the beam direction can be recovered by applying electron tomography, but this is a relatively new technique to defect studies and despite its potential it remains a static snapshot. In this talk, I will illustrate how time-resolved deformation studies have improved our understanding of the behavior of dislocations and how this information has informed the development of new models. I will also demonstrate how three-dimensional images yield a better understanding of complex dislocation interactions and configurations. Finally, I will address the challenges faced in combining these two techniques such that three-dimensional snapshots of the evolving microstructure can be acquired periodically.