Accelerator-based single-shot ultrafast transmission electron microscope with picosecond temporal resolution and nanometer spatial resolution

AbstractMicrochip technology with electron transparent membranes is a key component for in situ liquid transmission electron microscope (TEM) characterization. The membranes can significantly influence the TEM imaging spatial resolution, not only due to introducing additional material layers but also due to the associated bulging. The membrane bulging is largely defined by the membrane materials, thickness, and short dimension. The impact of the membrane on the spatial resolution, especially the extent of its bulging, was systematically investigated through the impact on the signal-to-noise ratio, chromatic aberration, and beam broadening. The optimization of the membrane parameters is the key component when designing the in situ TEM liquid cell. The optimal membrane thickness of 50 nm was found which balances the impact of membrane bulging and membrane thickness. Beyond this, the short membrane window dimension and the chip nominal spacing should be minimized. However, these two parameters have practical limitations in regards to chip handling.

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Absolute magnetometry at nanometer transverse spatial resolution: Holography of thin cobalt films in a scanning transmission electron microscope

Journal of Applied Physics ◽

10.1063/1.356658 ◽

1994 ◽

Vol 75 (11) ◽

pp. 7418-7424 ◽

Cited By ~ 40

Author(s):

Marian Mankos ◽

M. R. Scheinfein ◽

J. M. Cowley

Keyword(s):

Electron Microscope ◽

Spatial Resolution ◽

Transmission Electron Microscope ◽

Scanning Transmission Electron Microscope ◽

Scanning Transmission Electron ◽

Cobalt Films ◽

Transmission Electron ◽

Scanning Transmission

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Quantification of electron–phonon scattering for determination of temperature variations at high spatial resolution in the transmission electron microscope

Nanotechnology ◽

10.1088/0957-4484/23/20/205705 ◽

2012 ◽

Vol 23 (20) ◽

pp. 205705 ◽

Cited By ~ 10

Author(s):

Li He ◽

Robert Hull

Keyword(s):

Electron Microscope ◽

Spatial Resolution ◽

Transmission Electron Microscope ◽

Phonon Scattering ◽

High Spatial Resolution ◽

Temperature Variations ◽

Transmission Electron ◽

Electron Phonon Scattering

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In-situ Observations of Martensitic Transformation in Pure Ti Thin Films using the Dynamical Transmission Electron Microscope (DTEM)

MRS Proceedings ◽

10.1557/proc-0907-mm05-02 ◽

2005 ◽

Vol 907 ◽

Cited By ~ 1

Author(s):

Thomas Bradley LaGrange ◽

Geoffrey H. Campbell ◽

Jeffrey D. Colvin ◽

Wayne E. King ◽

Nigel D. Browning ◽

...

Keyword(s):

Electron Microscope ◽

Martensitic Transformation ◽

Electron Diffraction ◽

Transmission Electron Microscope ◽

Diffusion Mechanism ◽

Single Shot ◽

Transmission Electron ◽

Texture Modification ◽

Diffraction Patterns ◽

Ti Films

AbstractWe have measured the transient events of the α-β martensitic transformation in nanocrystalline Ti films via single shot electron diffraction patterns with 1.5 ns temporal resolution. This was accomplished with a newly constructed dynamic transmission electron microscope (DTEM), which combines pulsed laser systems and pump-probe techniques with a conventional TEM. The DTEM thereby enables studies of transformations that are (1) far too fast to be captured by conventional bulk techniques, and (2) difficult to study with current ultrafast electron diffraction (UED) instruments (which typically require an accumulation of multiple shots for each diffraction pattern). Martensitic transformations in nanocrystalline materials meet both criteria, with their rapid nucleation, characteristic interface velocities ∼1 km/s, and significant irreversible microstructural changes. Free-standing 40-nm-thick Ti films were laser-heated at a rate of ∼1010 K/s to a temperature above the 1155 K transition point, then probed at various time intervals with a 1.5-ns-long intense electron pulse. Diffraction patterns show an almost complete transition to the β phase within 500 ns. Post-mortem analysis (after the sample is allowed to cool) shows a reversion to the α phase coupled with substantial grain growth, lath formation, and texture modification. The cooled material also shows a complete lack of apparent dislocations, suggesting the possible importance of a "massive" short-range diffusion mechanism.

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Facility Implementation and Comparative Performance Evaluation of Probe-Corrected TEM/STEM with Schottky and Cold Field Emission Illumination

Microscopy and Microanalysis ◽

10.1017/s1431927612014298 ◽

2013 ◽

Vol 19 (2) ◽

pp. 487-495 ◽

Cited By ~ 6

Author(s):

Yan Xin ◽

John Kynoch ◽

Ke Han ◽

Zhiyong Liang ◽

Peter J. Lee ◽

...

Keyword(s):

Performance Evaluation ◽

Electron Microscope ◽

Field Emission ◽

Spatial Resolution ◽

Energy Resolution ◽

Transmission Electron Microscope ◽

Thermal Field ◽

Scanning Transmission Electron Microscope ◽

Comparative Performance ◽

Transmission Electron

AbstractWe report the installation and performance evaluation of a probe aberration-corrected high-resolution JEOL JEM-ARM200F transmission electron microscope (TEM). We provide details on construction of the room that enables us to obtain scanning transmission electron microscope (STEM) data without any evident distortions/noise from the external environment. The microscope routinely delivers expected performance. We show that the highest STEM spatial resolution and energy resolution achieved with this microscope are 0.078 nm and 0.34 eV, respectively. We report a direct comparative evaluation of the performance of this microscope with a Schottky thermal field-emission gun versus a cold field-emission gun. Cold field-emission illumination improves spatial resolution of the high current probe for analytical spectroscopy, the TEM information limit, and the electron energy resolution compared to the Schottky thermal field-emission source.

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