Hi John,
Thanks for the reply. I wonder if anybody has tried operating their EPMA in variable pressure mode yet? If not, then I guess it’s only a matter of time. We have spoken with some folks from Shimadzu about developing one, but so far they haven’t taken the bait.
Just an update, it turns out that the Bruker XSense is limited to less than about 3.6 keV, which is a bit restrictive if we are working with a 30 kV beam. We have learned from EDAX that their TEXS WDS system is also capable of operating in VP/enviro mode. Its range extends up to 15 keV with the proper crystal configuration. Unfortunately, it is also a parallel beam WDS system, so I can image there should be be significant loss of signal and spectral resolution for higher energy x-rays. Also, the x-ray optics need to be near to the sample, so that’s a limitation for heating stage experiments. It seems Oxford is the only manufacturer still using Rowland circle geometry, but their system is not currently compatible with VP/enviro.
Another idea is to forget WDS and simply add a thick window to an EDS system in order to block out IR and visible coming off the glowing hot sample (sort of like sunglasses). Bruker had previously developed a removable polymer thick window for an EDS fitted to a beamline heating stage system. EDAX, meanwhile, can manufacture a permanent SiN thick window (1 micron thickness), to achieve the same result.
Cheers,
Jason