TEM cluster: Applications & Instruments

FACTS have 2 LaB6 TEMs and 2 FEG-TEMs.

TEMs are capable of TEM illumination mode, where a thin section sample is illuminated with an electron beam, and the resultant diffraction of the electron beam allows for imaging and diffraction pattern collection for visualisation of samples and crystal structure determination.

FACTS FEG TEMs are additionally equipped with STEM detectors to allow for a scanning probe to be used for image formation, use of Convergent Beam Electron Diffraction (CBED) techniques and x-ray / EELS signal collection. This further allow the FEG TEMs to conduct elemental analysis and bonding information collected from the samples examined.

Aberration-corrected TEMs are "racehorse" TEMs which attempts to provide atomic resolution imaging, by the use of image and probe correctors, in order to correct any aberrations that limits imaging resolution with convention TEMs. 

FACTS has 2 ACTEMs, running at an acceleration voltage of 300kV and 200kV.

The ARM300F can operate at 300kV in TEM Mode with an Image Corrector and in STEM Mode with a Probe Corrector; and is both equipped with a large area XEDS detector and an EELS detector. The ARM300F is capable of both 3D tomography and electron holography.

The ARM200F can operate at 200kV in STEM Mode with a Probe Corrector, and is equipped with a large area XEDS detector.

Both ACTEMs have a fast Gatan One-View CMOS Camera 4k x 4k, suitable for imaging of in-situ experiments, 

In-situ experiments can also be performed, during TEM imaging. This include heating, cooling, biasing of either solid or liquid samples. We have specialised TEM sample holders to perform these functions when required.

CryoTEM can also be performed by using a cryogenic holder to maintain samples at cryogenic temperatures. This allows soft materials to be imaged with a lower electron dose and acceleration voltage, to avoid beam damage

Sample preparation involves preparing sample to be analyzed, into a thin cross-section, which is placed in the electron beam illumination path. For colloidal samples, this can be drop casted on a copper grid and dried. Bulk samples can be either prepared as a into a small thin section by mechanical means, or by ion milling methods such as using the Focused Ion Beam (FIB).

FACTS has a FIB for TEM lamellae preparation. The FIB is a versatile analytical tool for materials science, semiconductor industry, etc. It is built on a FESEM platform for site-specific analysis, cross-sectioning, deposition and removal of materials, TEM lamella preparation and so on. The FIB is equipped with a Ga ion beam, Pt and C gas injection systems and an in-situ manipulator for lamella preparation and nanofabrication work.