New transmission detector for high resolution low voltage scanning tunnelling electron microscope gives excellent contrast on low density materials
The S-5200 ultra-high resolution field emission scanning electron microscope (Fesem) from Hitachi High-Technologies can now be equipped with a transmission detector to allow scanning transmission images to be produced.
With this combination, scanning transmission electron microscopy can be carried out at low accelerating voltages.
This configuration gives excellent contrast on low density materials and samples composed from low atomic number elements.
This makes it particularly useful for studies of biological sections.
The S-5200 has an in-lens geometry which brings ultra-high resolution in secondary electron imaging mode.
The new transmission detector is positioned below a bright field aperture directly below the pole piece of the objective lens.
The system offers a resolution of 0.6nm at 30 kV in Stem mode, with a maximum magnification of approximately two million times.
Since the specimen is positioned inside the lens gap, normal geometry for both secondary electron imaging and X-ray collection is maintained.
The take-off angle for the optional energy dispersive X-ray (EDX) detector is 20 degrees.
