Environmental Scanning Electron Microscopy

The Center for Environmental Scanning Electron Microscopy (CESEM) was set up in 1998, CESEM is located within a purpose built room within the Conoco Building, and is equipped with a Philips XL30 Environmental Scanning Electron Microscope (ESEM), and an Oxfod Instruments INCA energy dispersive x-ray system.

These can be used to image and / or analyse virtually any substance, including wet oily and outgassing samples that cannot be examined by more conventional SEM's. The facility was opened primarily to foster research within Heriot-Watt University, but is also open to other institutions and companies.

About

An Environmental Scanning Electron Microscope (ESEM) is specifically designed to be able to examine microstructural and ultrastructural details of samples, within an SEM chamber, in their uncoated natural state. An ESEM is able to examine wet, oily and outgassing samples, without any form of preparation, and is able to maintain specimens within their natural state for prolonged periods within the ESEM viewing chamber. The ESEM works at low vacuum (typically 2 - 6 Torr), and utilizes a chamber gas for imaging, charge surpression and sample humidity.

ESEM is specifically suited to dynamic experimentation of the micron scale and below. ESEM technology allows for dynamic experiments involving fluids, and the possibility of imaging samples undergoing compression and tension. ESEM can therefore be regarded as a micro dynamic experimentation chamber where materials can be examined at a range of mechanical loads, temperatures, under a variety of gases/fluids.

For further specific information about ESEM visit the Philips-FEI website, or feel free to contact staff at CESEM.

Facilities

The XL30 ESEM at Heriot-Watt University is capable of operating in three modes:

• High vacuum
• Low vacuum
• Environmental/wet mode

This gives the facility the flexibility to be able to physically examine virtually any substance, including liquids. The ESEM is also equipped with a full energy dispersive x-ray analysis package (EDX), which is available in all modes.