Micron 68 (2014) 140
Contents lists available at ScienceDirect
Micron journal homepage: www.elsevier.com/locate/micron
Preface
This volume of Micron highlights a cross section of presentations from the Symposium on “Electron Microscopy of Materials”, which was held during the XXII International Materials Congress in Cancun, Mexico, August 11–15, 2013. Similar to previous symposia in 2006 and 2011 it focuses on the advancement and application of leading-edge, aberration-corrected transmission electron microscopy. These meetings were held during a time period of ground breaking innovations that were driven by projects such as TEAM (http://ncem.lbl.gov/TEAM-project/index.html), CREST (http://www.jst.go.jp/kisoken/crest/), SALVE (http://www.salveproject.de) or others, which enabled the detection of single atoms across the Periodic Table of Elements at deep sub-Ångstrom resolution with electron beams of variable voltages between 15 kV and 300 kV. In the wake of these projects it became clear that such equipment operates now at the edge of physical limits to resolution that is set as much by technology as it is set by beam-sample interactions. A majority of current, advanced applications decode the electronic and atomic structure of materials together with their chemical composition at a resolution of one Ångstrom or less. Scientifically, they provide astounding insight into the static structure of matter as long as irradiation effects are negligible or suitably controlled. Some of them are documented in this contribution. Nevertheless, any argument in favor of resolution improvement can no longer serve as the only driving force to further improve on microscope performance. Alternatives are sought and they are extraordinary rich. Most outstanding are concepts and applications that capture the time evolution of materials or reveal dynamic processes and functionality at the atomic scale. They include the exciting perspective to directly observe chemical reactions at a relevant temperature and pressure, or the long-sought ability to recover the threedimensional structure of matter at atomic resolutions from a single or only a few projections. In any such advanced applications, the control of beam–sample interactions is mandatory to understand the reversible or irreversible nature of the observed sample
http://dx.doi.org/10.1016/j.micron.2014.09.001 0968-4328/© 2014 Published by Elsevier Ltd.
excitations. It is now established that dose rates on a level of atto - or zepto Amperes per square Ångstrom are at least as relevant to the detection of single particle trajectories as a variation of the acceleration voltage. In these conditions it seems feasible to even strive for the imaging of single molecules and to capture their function, which is a challenging goal that currently cannot be met by any other experimental tool. In this situation it is natural that the debate of how to progress in the field is very rich and contributions like the one from Van Dyck et al. gave rise to considerable discussion with Micron reviewers. We eventually decided to include all aspects in the Special Issue because we believe it is essential to present all authors’ arguments in a clear and concise fashion, so that other researchers can evaluate them and the implications involved. Nevertheless, it becomes also clear that the climax of electron microscopy is yet to come since it is expectable that investigations of functional behavior of nanocrystals and even molecules will greatly benefit from these developments. As organizers of the symposia in the IMRC meetings we thank the Sociedad Mexicana de Materiales and the Materials Research Society for the opportunity to participate in such events. Additionally all speakers are acknowledged for the extraordinary quality of their presentations, as well as FEI and CONACYT (Grant 148304) for financial support. In particular, we would like to thank Prof. R.F. Egerton, Editor Physical Sciences for Micron, for his experienced advice on many occasions during the editorial process of this special issue. Finally, we point out that the papers with the guest editors as authors were edited at arms length. G.A. Botton H.A. Calderon C. Kisielowski E-mail address: [email protected] (H.A. Calderon) Available online 6 September 2014
Contents lists available at ScienceDirect
Micron journal homepage: www.elsevier.com/locate/micron
Preface
This volume of Micron highlights a cross section of presentations from the Symposium on “Electron Microscopy of Materials”, which was held during the XXII International Materials Congress in Cancun, Mexico, August 11–15, 2013. Similar to previous symposia in 2006 and 2011 it focuses on the advancement and application of leading-edge, aberration-corrected transmission electron microscopy. These meetings were held during a time period of ground breaking innovations that were driven by projects such as TEAM (http://ncem.lbl.gov/TEAM-project/index.html), CREST (http://www.jst.go.jp/kisoken/crest/), SALVE (http://www.salveproject.de) or others, which enabled the detection of single atoms across the Periodic Table of Elements at deep sub-Ångstrom resolution with electron beams of variable voltages between 15 kV and 300 kV. In the wake of these projects it became clear that such equipment operates now at the edge of physical limits to resolution that is set as much by technology as it is set by beam-sample interactions. A majority of current, advanced applications decode the electronic and atomic structure of materials together with their chemical composition at a resolution of one Ångstrom or less. Scientifically, they provide astounding insight into the static structure of matter as long as irradiation effects are negligible or suitably controlled. Some of them are documented in this contribution. Nevertheless, any argument in favor of resolution improvement can no longer serve as the only driving force to further improve on microscope performance. Alternatives are sought and they are extraordinary rich. Most outstanding are concepts and applications that capture the time evolution of materials or reveal dynamic processes and functionality at the atomic scale. They include the exciting perspective to directly observe chemical reactions at a relevant temperature and pressure, or the long-sought ability to recover the threedimensional structure of matter at atomic resolutions from a single or only a few projections. In any such advanced applications, the control of beam–sample interactions is mandatory to understand the reversible or irreversible nature of the observed sample
http://dx.doi.org/10.1016/j.micron.2014.09.001 0968-4328/© 2014 Published by Elsevier Ltd.
excitations. It is now established that dose rates on a level of atto - or zepto Amperes per square Ångstrom are at least as relevant to the detection of single particle trajectories as a variation of the acceleration voltage. In these conditions it seems feasible to even strive for the imaging of single molecules and to capture their function, which is a challenging goal that currently cannot be met by any other experimental tool. In this situation it is natural that the debate of how to progress in the field is very rich and contributions like the one from Van Dyck et al. gave rise to considerable discussion with Micron reviewers. We eventually decided to include all aspects in the Special Issue because we believe it is essential to present all authors’ arguments in a clear and concise fashion, so that other researchers can evaluate them and the implications involved. Nevertheless, it becomes also clear that the climax of electron microscopy is yet to come since it is expectable that investigations of functional behavior of nanocrystals and even molecules will greatly benefit from these developments. As organizers of the symposia in the IMRC meetings we thank the Sociedad Mexicana de Materiales and the Materials Research Society for the opportunity to participate in such events. Additionally all speakers are acknowledged for the extraordinary quality of their presentations, as well as FEI and CONACYT (Grant 148304) for financial support. In particular, we would like to thank Prof. R.F. Egerton, Editor Physical Sciences for Micron, for his experienced advice on many occasions during the editorial process of this special issue. Finally, we point out that the papers with the guest editors as authors were edited at arms length. G.A. Botton H.A. Calderon C. Kisielowski E-mail address: [email protected] (H.A. Calderon) Available online 6 September 2014
