FEI Quanta 650 FEG SEM

The FEI Quanta 650 FEG scanning electron microscope (SEM) is used for high-resolution imaging and semi-quantitative X-ray microanalysis of both conductive and non-conductive specimens at nanometer resolution (magnification range from 5-1,000,000x).

The FEI Quanta 650 FEG has two modes:

• Variable pressure (VP) mode (pressure range 100-200Pa)
  Used for high-resolution imaging of non-conductive samples in both secondary electron and backscatter modes.
• High-vacuum (HV) mode (pressure range 10^-2-10^-4 Pa)
  Used for high-resolution imaging of conductive samples in both secondary electron (SE) and backscattered (BSE) modes.

It is equipped with the following accessories and features:

• a low-vacuum cone, mounted on the final lens, for low-kV imaging under VP conditions to improve imaging of surfaces, with reduced beam penetration
• a beam sleeve, mounted on the final lens, to improve the performance of Energy Dispersive X-ray micro-analysis (EDX) in VP conditions by reducing beam skirt
• beam-deceleration (BD) mode for ultra-high resolution backscatter imaging of flat samples under HV conditions
• drift-correction mode for imaging highly charging samples
• MAPS software for tiling and creating large montage images at high resolution, which allows for automated image collection of large areas or multiple areas
• custom-built vacuum pumping system allowing for slow and fully controllable pump down time for specimens sensitive to rapid decompression rates
• additional micro tilt/rotate stage (Deben) for high-precision work on small, demanding samples, e.g. pinned insects
• Bruker Flat Quad 5060F energy dispersive X-ray detector (EDS) for ultra-fast and shadow-free elemental analysis and hyperspectral mapping, even on samples that are non-conductive and highly topographic

Recent applications

• large area elemental mapping of fossilised arthropods
• high-resolution backscattered (BSE) imaging of very fine scale mineral particles