Joachim Mayer
Aberration Corrected TEM:
State of the Art and Future Challenges in Data Acquisition and Analysis
The invention of aberration correctors has revolutionized the development of TEM and STEM instrumentation. Only shortly after the development and installation of the first TEM with a corrector for the spherical aberration [1], commercial instruments with aberration correctors are now offered by all major manufacturers. In order to provide a platform for these novel developments and based on the experience with the first aberration corrected TEM [2-4], Research Centre Juelich and RWTH Aachen University have jointly founded the Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C) [5]. At the Ernst Ruska-Centre we have recently installed the FEI Titan 60-300 PICO. PICO is a fourth-generation transmission electron microscope capable of obtaining high-resolution transmission electron microscopy images approaching 50 pm resolution in the CC- and CS-corrected mode at 300 keV. It is currently one of only two microscopes in the world capable of chromatic aberration correction [6].
In the present contribution we will report on the initial results obtained with the PICO instrument. In the PICO instrument, HRTEM images can be obtained with simultaneous correction of the spherical and the chromatic aberration. Furthermore, a spherical aberration corrector also exists in the illumination system for Cs-corrected STEM imaging. The benefits of chromatic aberration corrected imaging are particularly large for HRTEM imaging at low accelerating voltages and for energy filtered (EFTEM) imaging with large energy window width [7]. In the present contribution we will focus on new applications and resulting challenges for data acquisition and analysis.
References:
[1] M. Haider, H. Rose, S. Uhlemann, E. Schwan, B. Kabius, and K. Urban, Nature 392 (1998) 768.
[2] M. Lentzen, B. Jahnen, C.L. Jia, K. Tillmann, and K. Urban, Ultramicroscopy 92 (2002) 233.
[3] C.L. Jia, M. Lentzen, and K. Urban, Science 299 (2003) 870.
[4] C. L. Jia, K. Urban, Science 303 (2004) 2001.
[5] http://www.er-c.org
[6] B. Kabius, P. Hartel, M. Haider, H. Müller, S. Uhlemann, U. Loebau, J. Zach, and H. Rose, J. Electron Microsc. 58, 147 (2009).
[7] K. Urban, J. Mayer, J. Jinschek, M. J. Neish, N. R. Lugg, and L. J. Allen, PRL 110, 185507 (2013)