An Australian Touch: An Environmental SEM
John Dunning

I thoroughly enjoyed my sabbatical visiting eastern Australia. My adventures took me to universities near the capital cities of the states of New South Wales and Queensland. They strive for excellence while emphasizing to their students those careers thought to be of most benefit to Australia.

I learned of their successes in teaching lower division physics laboratories. I sought out teaching strategies that they felt enhanced the retention rate of new physics majors. I also visited working Scanning Electron Microscope (SEM) laboratories, places where X-ray diffraction was in use, and nuclear facilities.

I discovered cohesive microanalysis centers functioning well as semiautonomous units within two universities. At the University of Technology, Sydney it is the Microstructural Analysis Unit. At the University of Queensland it goes by the name Centre for Microscopy and Microanalysis. Both centers have several transmission and scanning electron microscopes (SEMs) and X-ray diffraction. The staff initiate their own projects, furnish technical support, and collaborate on the imaging portion of other projects. Their main source of funding is from the University.

The most recent purchases by both centers are Philips XL-30 SEMs. This is the very make and model that we are proposing for SSU. Both Australian centers concluded that these SEMs are easy to operate, versatile machines with superior repair records.

The Environmental option on the Philips XL-30 ESEM was purchased by the Microstructural Analysis Unit. This option allows the sample to be bathed in up to 20 mm water vapor pressure while still being viewed at a full resolution of three nanometers. The vapor pressure of water at 4 °C is only 6 mm. In a water vapor environment, a biological sample cooled to this temperature will not dry out, and it is above freezing. Environmental samples with water content will retain their structure. The 6 mm water vapor pressure is also high enough to leak off charge so that no sample coating is needed, so there is no sample preparation. The elemental analysis addition called Energy Dispersive X-ray (EDX) works just fine with the short working distance possible in a Philips instrument.

SSU needs in-house research capability to keep our faculty sharp, attract new faculty, and interest today’s students. An Environmental SEM with EDX will be of use here over a broad range of disciplines. Biology, Geology, Physics, and Chemistry all stand to benefit. This unit nicely complements our existing X-ray powder diffraction instrument, which measures dimensions on the order of 0.1 nm. With this addition we too will have modern microanalysis capability.

I solicited bids for the XL-30-ESEM and for the EDX system. You say the price of $284,989 is the catch. Actually this price is lower than we were quoted three years ago for an instrument without water vapor capability. The computing power today is six to ten times greater. Help us find the funds. You will be proud of your alma mater.