Collaborative Laboratory and User Facility for Electron Microscopy

In-situ electron microscopy

In-situ mechanical tests

In-situ tensile tests of single crystal gold nanowires: The dark field image shows a deformed 100nm wide nanowire with planar defects lying on two sets of {111}-planes which appear during straining of the wire. The spot used for imaging is circled in the diffraction pattern inset and the cross-section of a typical wire is shown in the bright field inset. The defects are identified as stacking faults formed due to the surface nucleation and motion of partial dislocations.
Reference:B. Roos, B. Kapelle, G. Richter, and C. A. Volkert, Surface dislocation nucleation controlled deformation of Au nanowires, Applied Physics Letters 105, 201908 (2014).

High resolution in-situ electron microscopy

Time series of HRTEM images showing the recrystallization of an initially amorphous edge (marked with white arrowheads) of a PCMO film in water vapor at pH2O = 47 µbar and an electron flux of 3.7 x 104 e/Å2s. The initial state is shown in the top image at t = 0 min.
Ch. Jooss, S. Mildner, M. Beleggia, D. Mierwaldt, V. Roddatis, ETEM book :Controlled Atmosphere Transmission Electron Microscopy - Principles and Practice.

High resolution electron microscopy

Iterative image series matching at an interface of crystalline Si and amorphous Ge. (a) shows an averaged high-resolution TEM images, (b) a computed two-dimensional atom distribution function which was fitted to the experimental results. This allows estimating the width of the ordered transition region in the amorphous Ge and the bond angle between atoms in this area.
Karsten Thiel, N.Borgardt, B.Plikat, M.Seibt, Ultramicroscopy 126,1 (2013).

Electron beam induced current (EBIC)

Electron beam induced current image obtained in the FEI Nova Nanolab focused ion beam microscope. This technique highlights a recombination-active defect at a grain boundary in multicrystalline block-cast silicon contaminated with Cu and Fe. To analyse the defect structure, a TEM lamella is prepared in the area marked by the a Pt:C patch. The lamella preparation can be performed in-situ in the focused ion beam microscope.
M.A. Falkenberg, H. Schuhmann, M. Seibt, V. Radisch, Rev. Sci. Instr. 81,063705 (2010).

Electron Energy Loss Spectroscopy (EELS)

As an example a EELS spectra measured in HRSTEM mode of a rutile TiO2 single crystal is shown in the picture below. Here a dispersion of 0.05 eV/channel was used revealing the TiO2 fine structure in the L3,2 energy edges as well as a detailed O-K edge.