Good morning, everyone:
Has anyone out there ever bought or used the JEOL SXES soft x-ray detector, especially for Li determination? Likes or dislikes? Pros and cons? Ease of use vs difficulties and limitations? We are looking at purchasing one of these systems for our JXA 8200, and I thought I'd ask, in case anyone outthere had any helpful advice. Thanks very much!
Kind regards
Dan MacDonald
Probe Dude
Dalhousie University
Quote from: Dan MacDonald on July 19, 2016, 07:00:40 AM
Has anyone out there ever bought or used the JEOL SXES soft x-ray detector, especially for Li determination? Likes or dislikes? Pros and cons? Ease of use vs difficulties and limitations? We are looking at purchasing one of these systems for our JXA 8200, and I thought I'd ask, in case anyone outthere had any helpful advice.
Hi Dan,
I didn't know that JEOL was making this spectrometer available for older instruments... very cool.
I wonder if JEOL would be willing to provide an API (application programming interface) so one could acquire these low energy spectra into Probe for EPMA. Similar to how we acquire already spectra for EDS and CL in Probe for EPMA. You should be sure to get a commitment from JEOL for them to provide such an API as part of your SXES spectrometer purchase if you decide to do this.
I not sure what exactly one could do with these spectra with regards to quantification (calibration curve methods?), but getting them into a database would be a great start.
I suppose this interest is because Dalhousie is a center for Li- ion battery research?
http://www.dal.ca/diff/dahn/people/jeff_dahn.html
Pretty exciting stuff.
john
I have some experience. I send you a message.
Quote from: Anette von der Handt on July 19, 2016, 06:25:14 PM
I have some experience. I send you a message.
Please send me a message as well!
and here please....
Hi all,
I found one discussion about this JEOL detector from the year 2016, which was only some posts long - therefore, I decided to start a new one.
a) I would be interested if someone has experience / recommendations for using the SXES-ER detector as a substitution for one WDS spec (since the SXES would require one WDS port)?
--> The energy range of the JS2000 model (350-2300 eV) would cover the Ka energies for elements from N to P. The energy resolution would be comparable to a WDS system.
b) Has someone experience to determine Fe2+/Fe3+ (or valence states for other elements) by using the SXES detector?
Thanks
Dirk
I believe there's now an option to fit it to an EDS port rather than sacrifice a WDS.
We have the SXES-ER on our EDS port and an EDS on the other port so we have not sacrificed a WDS.
Quote from: DirkMueller on February 05, 2024, 03:11:43 AM
I found one discussion about this JEOL detector from the year 2016, which was only some posts long - therefore, I decided to start a new one.
We merged these two topics as it is probably better to keep these posts together.
As you mentioned there are some other posts discussing SXES spectrometers. See also these posts where Jon Fellowes asks for some mods to the PFE software (dead time sanity check) to allow him to treat the SXES spectrometer as a WDS spectrometer.:
https://smf.probesoftware.com/index.php?topic=71.msg11872#msg11872
Thanks for the info regarding the port occupation (from Jeol I got the info that one WDS port is required ???) - I'll ask one more time...
However, my question was more, if someone uses the SXES detector for full-quantitative analysis? If it is comparable to a WDS?
So far, I can only see benefits:
- faster analysis, since all elements are measured simultaneously
- no need for regular calibration, since no moving parts and no gas (maybe temperature plays a role?)
I'll chime in here, as I get a lot of use out of our SXES (-LR rather than -ER though).
Regarding the WDS vs EDS port mounting, it depends on what chamber you have. The 8x30 series chambers (8230 and 8530F) and earlier have the SXES fitted to either WDS port 1 or 5 (i.e the two ports either side of the airlock), whereas I've been told the new iHP200F has a modified EDS port so that you can fit the SXES there instead (with a higher take off angle). You can see this arrangement on the front cover of the JEOL SXES brochure (from https://www.jeol.com/download_catalogues.php#sem_fe_op (https://www.jeol.com/download_catalogues.php#sem_fe_op)).
If you're looking for a new machine, then you'll be asking for the SXES-EREP (or the SXES-LREP), where the EP = "EDS Port".
I've spent quite a lot of time getting my head around the best way of using the SXES-LR, as its quite a different beast compared to the WDS and EDS. The -LR (low range) comes with the JS50XL and the JS200N diffraction gratings, and these really are low energy (the energy of the C Ka is way too high for example, I have to use the 2nd order reflection or higher). The JS300N grating in the SXES-ER(/EP) looks to be pretty similar to the JS200N, so it'll be really for light element/soft X-ray use (and the all the complications that entails).
The JS2000 has a waaaay bigger energy range than the other three diffraction crystals, ranging from the smaller d spacing LDE crystals up through the TAP range and in to the bottom of the PET energy range. The CSIRO folks had a talk a while back where they compared the spectral resolution of the JS2000 grating across its range and found it was favourable relative to TAP for most of that range, but is notably worse than PET at the high energy end.
The big draw back of the SXES that I can think of are:
(i) time - and lots of it! - the SXES CCD is pretty slow. This is negated slightly by counting all elements and all backgrounds simultaneously, but you'll still be counting for 100s if not 1000s of msec per spectrum at the very least. This makes for some very long maps. Quantitative points would be possible, but you'll have some software to write!
(ii) it's bloomin' cold. The SXES CCD sits unprotected in your sample chamber at -70C, ensuring that any contamination you have in your system will sit on the CCD pretty rapidly - you're effectvely cryo-pumping your sample chamber. You'll either need to use the liquid nitrogen anticontamination device permanently (which is a nuisance when you have to fill up the dewar twice a day, and letting it run dry will crash the vacuum), or design your own anti-contamination device (I've built an in vacuo Peltier based system).
Overall, I think the SXES is worth it. It's a big step forward in light element analysis, with much higher spectral resolution and essentially no deadtime to worry about. I don't think it's a replacement for WDS and GFPC, but it's another useful detector alongside the WDS and EDS.
Quote from: JonF on February 08, 2024, 02:46:38 AM
The big draw back of the SXES that I can think of are:
(i) time - and lots of it! - the SXES CCD is pretty slow. This is negated slightly by counting all elements and all backgrounds simultaneously, but you'll still be counting for 100s if not 1000s of msec per spectrum at the very least. This makes for some very long maps. Quantitative points would be possible, but you'll have some software to write!
...
Overall, I think the SXES is worth it. It's a big step forward in light element analysis, with much higher spectral resolution and essentially no deadtime to worry about. I don't think it's a replacement for WDS and GFPC, but it's another useful detector alongside the WDS and EDS.
Awesome information, thanks for sharing this!
Previously in this topic you asked us (Probe Software) to modify the allowable range of dead time values (and we did) because you said you wanted to reprocess SXES data using our software. Could you expand upon that aspect? How exactly do you utilize SXES data in our software? You acquire the SXES data with your own app? Then you write it yourself as a PrbImg file? And then reprocess it in CalcImage? Could you detail these steps for us?
We are very curious how you do these things and if there's anything we could do to further facilitate this processing.
Quote from: John Donovan on February 08, 2024, 08:38:40 AM
Awesome information, thanks for sharing this!
Previously in this topic you asked us (Probe Software) to modify the allowable range of dead time values (and we did) because you said you wanted to reprocess SXES data using our software. Could you expand upon that aspect? How exactly do you utilize SXES data in our software? You acquire the SXES data with your own app? Then you write it yourself as a PrbImg file? And then reprocess it in CalcImage? Could you detail these steps for us?
We are very curious how you do these things and if there's anything we could do to further facilitate this processing.
Actually, I eventually decided against reinventing the wheel and just went with acquiring all the signals with the JEOL software (SE, BSE, CL, EDS, WDS and SXES).
Then its just the comparatively simple job of converting between file formats (SXES -> GRD) to get the information in to CalcImage, akin to the file conversions available in Probe Image.
Quote from: JonF on February 09, 2024, 02:25:42 AM
Quote from: John Donovan on February 08, 2024, 08:38:40 AM
Previously in this topic you asked us (Probe Software) to modify the allowable range of dead time values (and we did) because you said you wanted to reprocess SXES data using our software. Could you expand upon that aspect? How exactly do you utilize SXES data in our software? You acquire the SXES data with your own app? Then you write it yourself as a PrbImg file? And then reprocess it in CalcImage? Could you detail these steps for us?
We are very curious how you do these things and if there's anything we could do to further facilitate this processing.
Actually, I eventually decided against reinventing the wheel and just went with acquiring all the signals with the JEOL software (SE, BSE, CL, EDS, WDS and SXES).
Then its just the comparatively simple job of converting between file formats (SXES -> GRD) to get the information in to CalcImage, akin to the file conversions available in Probe Image.
That sounds quite reasonable.
Have you attempted to quantify any SXES signals in CalcImage?
Quote from: John Donovan on February 09, 2024, 08:00:04 AM
That sounds quite reasonable.
Have you attempted to quantify any SXES signals in CalcImage?
Yeah, it works really well! I'll speak with a couple of recent users and see if I can get some examples up.
I had a private message about the quantitative analysis of Li by EPMA-SXES and other SXES queries in general, and I thought I'd copy out the bulk of my reply here. All of the below is my interpretation of things based on my own experience, so read in to this what you will! I'm happy to be corrected by any stray physicists out there.
For the sake of clarity, I'd also say that I'm actually a fan of the SXES, but they aren't drop in replacements for WDS - they're another complementary detector alongside WDS and EDS that can provide a bit more information. To fully appreciate what the JS50XL, JS200N and JS300N gratings can tell you, you'll need to wander down the rabbit hole of "where do X-ray emissions come from and why do the peaks look the way they do?".
Regarding Li determination:
Quantitatively analysing Li by EPMA is a bit of a non-starter. It breaks one of the golden rules of microanalysis in that the Li Ka intensity varies as a function of not just concentration but also the form that it is in i.e. the Li Ka emission from Li metal and Li2O is not directly proportional to the concentration of Li in each phase (matrix corrections aside). Hovington et al have a paper on this that covers the basics (https://doi.org/10.1002/sca.21302), and in particular figure 2 (note the 1/5th scaling of the Li Ka in Li metal relative to the other Li phases).
To make matters worse, aside from the concentration =/= intensity, the peak shift and the peak shape changes, the Li is also readily beam damaged, forming Li metal (and so the Li Ka becomes more obvious during a course of analysis as the sample becomes damaged!). And then there's interference: for natural materials, the Fe Mz (M2,3-M4,5) is right in the way of Li Ka! A (very) high order reflection of the C Ka is knocking about down there too, which isn't helpful if you need to carbon coat your non-conductive samples (which will also effectively hinder the Li Ka making it out of the sample).
Qualitatively determining presence/absence and phase of Li might be possible depending on the phase that it is in - sometimes the Li just refuses to generate an X-ray. To see Li though, you'll need the JS50XL grating, which is only available on the SXES-LR along with the JS200N grating. The SXES-ER comes with the JS300N and JS2000 gratings. I've been told that the gratings aren't compatible between the -LR and -ER (I'd quite like the JS2000 grating myself!).
Regarding the slow CCD speed, it is definitely a bit of a hindrance, but these light elements (rather low energy transitions) just aren't favourable for X-ray emission, so the slow CCD speed is actually not as bad as it sounds: you need to count for 100s if not 1000s of seconds by WDS to get good counting statistics if you want to quantify. If you're looking for multiple light element/low energy emissions, then measuring for a few seconds to get all of them and the backgrounds isn't too bad. You can also measure using the WDS and EDS during this time, so there's two hyperspectral datacubes (EDS and SXES) plus the WDS maps for a single pass.
The slow CCD speed would also not be a problem for point analysis, however the software doesn't support automated acquisition of a series of points, so you'll be manually driving around and clicking "go" for each point - but at least the WDS are free to move around and measure as normal.
Regarding regular calibration: the SXES is quite stable relative to WDS as it is insensitive to barometric pressure and relative humidity fluctuations (i.e. why we need to keep re-standardising the GFPC - the sealed Xe detectors are much more stable). Well, at least as far as I've seen, anyway. That doesn't mean it doesn't need calibrating though! The energy axis is quite stable, but the intensity axis is quite sensitive to CCD temperature and the crud that will inevitably stick to the -70C CCD and absorb low energy X-rays (the cryo-pumping problem!).
Regarding cleaning of the SXES CCD: there's no window or anything between the sample and the CCD surface. It is the CCD itself that will become contaminated. The only way that you can clean this up is to turn the cooling off and allow it to warm up and hope everything that was on the CCD boils away in the vacuum. -70C shouldn't be cold enough to significantly capture water vapour under the chamber vacuum, but you shouldn't have the CCD cold during sample exchanges. If the crud on the CCD doesn't boil away, then it'll be an engineer visit to clean it up.
The time before the contamination builds up to the point where the SXES can't "see" will be variable depending on how often its used and how dirty the system is (and what the users try and put in there!). You can monitor the cleanliness of the system using your regular standards: the absorption by the muck layer will become apparent if you look at the intensity ratios between e.g. Al La and O Ka[3] over time (might not bee the best choice as the O Ka will get strongly absorbed as well!).