Physical Chemistry - Al-Shamery

Microscopes and instumentation

Jeol 2100F transmission electron microscope

The Jeol 2100F electron microscope is a high resolution scanning/transmission electron microscope equipped with Shottky field emission gun (FEG). It is well suited for material sciences, and can be operated at voltages between 80-200 kV in both, the transmission (TEM) mode and the scanning transmission (STEM) mode. Additionally, it offers chemical analysis and tomography capabilities. It is well suited for high-resolution imaging in the TEM mode, and atomic resolution can be achieved due to the high resolution objective lens polepiece. Z-contrast imaging is possible in the STEM mode using the bright field (BF) and annular dark field (HAADF) STEM detectors. Specimen tilts of ±30° are possible with the regular sample holder, tilts up to approximately ±80° with a high tilt holder. An Oxford energy dispersive X-ray analysis system allows elemental analysis. The high tilt holder in combination with the Tomography software allows 3D-rendering of samples. Digitized image documentation is achieved via two retractable CCD cameras.

 

Specifications of the Jeol 2100F S-TEM

Accelerating voltage

80 kV - 200 kV

Magnification

50x – 1,500,000x

Magnification steps

30 steps in Mag Mode (2,000x - 1,500,000x)

20 steps in Low Mag Mode (50x - 6,000x)

21 steps in SA Mag Mode (8,000x - 800,000x)

Resolution

0.14 nm lattice image

0.23 nm point image

Camera length steps

15 steps in SA DIFF (80-2,000mm)

14 steps in HD DIFF (4-80mm)

1 step in HR DIFF (333mm)

Objective lens polepiece

high resolution polepiece (HRP)

Focal length

2.3mm

Spherical aberration coefficient

1.0mm

Chromatic aberration coefficient

1.4mm

Minimum focal step

1.5nm

Exciting current stability

1 ppm/min.

Specimen stage

micro active goniometer

Specimen tilt angle

±35° (X-axis); ±30° (Y-axis)

Specimen movements

2.0mm (X); 2.0mm (Y); 0.4mm (Z) // (±0.2mm)

Additional equipment

EDX

Oxford INCA Energy TEM250 with SDD-Detector X-Max80 (area 80 mm2, resolution 129 eV at Mn K; detects elements from Be to Pu)

Tomography

High tilt specimen retainer; Jeol Tomography software packages for acquisition, 3D-reconstruction, and 3D-rendering

Image documentation

above the viewing screen: Gatan Orius SC200D (2k x 2k; side entry lens coupled camera; readout of up to 30fps)

below the viewing screen: Gatan Orius SC600 (2k x 2k; fiber optic coupled camera; readout of up to 13fps)

operating software: Gatan Digital Micrograph


Zeiss EM902A transmission electron microscope

The Zeiss EM902A TEM is our multi-purpose electron microscope. It is equipped with a tungsten hairpin cathode and is operated at 80 kV. It offers good image contrast due to its electron lens optics and, thus, is well suited for biological specimen obtained by negative staining or ultrathin sectioning, but also for non-biological, samples such as nanoparticles. New users are first trained on this microscope, and most of the teaching and education during courses are done on it. Digitized image documentation is achieved via a side entry CCD camera which is positioned above the viewing screen.

 

Specifications of the Zeiss EM902A TEM

Accelerating voltage

50 kV; 80 kV

Magnification (15 steps)

140x – 240,000x

Resolution

0.344 nm lattice image

0.5 nm point image

Camera length steps

5 steps in DIFF mode (390-3,500mm)

Specimen movements

2.0mm (X); 2.0mm (Y)

 

Additional equipment

Image documentation

Proscan High Speed SSCCD camera (1k x 1k) operated by the iTEM Five software

 

 

Hitachi S3200N variable pressure scanning electron microscope

This electron microscope is a conventional high resolution SEM with tungsten hairpin cathode and in which the vacuum level within the specimen chamber can be controlled. It is well suited for a wide variety of samples (try, wet, biological, non-biological, metals, minerals, etc.). Conductive samples are typically investigated in the high vacuum mode and images are collected with the Everhart-Thornley secondary electron (SE) detector. Non-conductive samples are examined in the variable pressure mode with the images becoming collected with the Robinson backscattered electron (BSE) detector. An Oxford cryo transfer system allows the preparation and imaging of shock-frozen, wet samples. Elemental analysis is enabled by an Oxford energy dispersive X-ray analysis system. Digitized image documentation is achieved via the Point Electronic DISS- and DIPS software packages.

As additional devices which are typically and often used for SEM preparations, a CPD030 critical point dryer and a SCD 005 sputter coater from Bal Tec are available.

 

Specifications of the Hitachi S3200N SEM

Accelerating voltage

300 V – 30 kV

Magnification

20x – 300,000x (in 63 steps)

Resolution

3.5 nm at 30kV in high vacuum mode using the SE detector

5.5 nm at 30kV in variable pressure mode using the BSE detector

Working distance

3-60 mm

Specimen rotation

360°

Specimen shift

80 mm x 40 mm

Specimen tilt

from -20° to +90°

Vacuum modes

high vacuum mode, variable pressure mode (1-270 Pa)

Additional equipment

EDX

Oxford INCA EDX system with 10 mm2 SDD detector (PentaFET Precision INCA X-act, 125 eV resolution, detects elements from Be to Pu)

Cryo

Oxford-Cryochamber-/Transfersystem CTS1500C

Documentation

Point Electronic DISS- and DIPS software packages
TIFF, JPG (1k x 1k, 2k x 2k, or 4k x 4k)