Transmission Electron Microscope JEOL JEM 2100F
The JEM-2100F, a Field Emission gun Transmission Electron Microscope, is a state of the art ultrahigh resolution analytical TEM that is capable of providing high spatial resolution atomic imaging and microstructure analysis of material samples.
By analytical characterization, we refer to determining the composition, crystallographic structure, chemical bonding, electronic structure, and mapping of electric and magnetic fields.
The imaging and spectroscopy methodologies we can employ in this lab are:
Phase-contrast (high-resolution) transmission electron microscopy (TEM).
Scanning TEM (STEM): High-angle annular dark-field (HAADF), Annular dark-field, Bright-field.
Lorentz TEM for magnetic imaging (Fresnel-contrast, field free region, 0.1 Oe, for the sample).
Off-axis electron holography for Lorentz TEM and for high-resolution TEM.
Electron Energy Loss Spectroscopy (EELS) including energy-filtered TEM (EFTEM).
Energy dispersive X-ray spectroscopy (EDS)
The main components of the microscope are:
Electron source: Schottky field-emission gun operating at accelerating voltages between 80 and 200 kV. The microscope is mostly operated at an accelerating voltage of 200 kV and energy spread of 0.8 eV.
Objective lens: ‘UHR’ pole-piece with a spherical aberration of approximately 0.5 mm. The TEM point resolution and information limit are 0.19 nm and 0.12 nm, respectively. The HAADF and BF STEM resolution are 0.2 nm.
Off-axis electron holography: JEOL biprism, 0.6 m diameter platinum wire.
EDS: JEOL 50 mm2 Si(Li) detector, solid angle 0.24 srad, energy resolution of 133 eV (Mn K edge).
EELS: GIF Quantum including a fast shutter (1000 spectra/sec).
STEM: JEOL bright-field and HAADF detectors; Gatan bright-field, dark-field and HAADF detectors. The latter detectors enable parallel acquisition of EELS and HAADF signal.
CCD camera (x2): Gatan Ultrascan 1000, 2k x 2k.
Sample holders: JEOL strong double tilt, Gatan analytical tilt/rotate, Gatan LN2 cooling, Fischione tomography.
For sample preparation, we have tripod mechanical polishing, 1010 Fischione ion miller and 1020 Fischione plasma cleaner.
Data analysis at a dedicated computer lab installed with Digital Micrograph, JEMS, MacTempas.