Coxem STEM Module: Scanning Transmission Electron Microscopy Detector

Coxem’s new scanning transmission electron microscopy (STEM) detector is designed with the ability to use the EM-30 Series Tabletop SEM or the CX-200plus SEM to perform STEM analysis with traditional TEM grids.

Powered by this optional accessory and Coxem’s 30 kV beam energy, SEM instruments of users can perform additional roles in the laboratory.

The STEM detector can be fitted to the SEM through a side port. When idle, the STEM detector is designed to retract and tilt to an angle of 90° out of view for typical SEM analysis.

Compared to other STEM modules wherein a platinum mirror is employed to acquire an image with the SE detector, the STEM module provides a true detector positioned below the TEM grid sample. The SEM detector can capture both Bright Field (BF) and Dark Field (DF) images.

Apart from the detector, the STEM accessory includes a dedicated TEM grid holder that can be fitted to the SEM Stage directly. Up to four separate TEM grids can be placed in the TEM grid holder. Moreover, the TEM grid holder has been built to perform EDS analysis without any exclusive modification or obstruction.

One of the most successful applications of the STEM module is to establish the size and morphology of nanoparticles spread onto TEM grids with carbon support films or with silicon nitride support films.

While it is possible to utilize the STEM adapter for traditional thin-section tissue examination, the 30 kV beam energy may require thinner tissue sections than traditional transmission electron microscopes (TEM) with beam energies of 80–200 kV.

In general, an Ultra-Microtome is needed to prepare adequate tissue samples, but the STEM module with the SEM can still be utilized for pre-screening of samples prior to basic TEM analysis, TEM analysis, or as a practical teaching instrument for TEM analysis.

Specifications of the Coxem STEM Module for SEM

Both Bright Field (BF) and Dark Field (DF) imaging can be performed

Retractable detector

Detector position can be modified

The sample holder is available for four TEM grids

X-Y Stage is available to position any of the four sample locations

NS 4.0 software comprises a dedicated detector image channel