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Waterloo Advanced Technology
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What's NeXT
15 Dec 2017 - Merry Christmas and Happy New Year! - As WATLab must transition to a totally self-sufficient operating model in an increasingly challenging environment in the next two years, we are grateful to have the support of our loyal users. In the past several months, some of the our machines have clearly shown their age and experienced unforeseen downtime intermittently. We thank our users for their patience and their understanding while we struggle to fix these systems without a service contract. The University will close by Dec 22, and we take this opportunity to wish our users the merriest holiday season, the best of luck in their research endeavour, and prosperous data mining to come in 2018!
10 Nov 2017 - LEO
resuming user service
- We are bringing the LEO
back online and into user service. The probe current is lower than
spec but it is extremely stable (with variation less than 5%). The
image quality is also good. Please limit the EHT to not greater than 15 kV
(as anything higher than 15 kV could cause arcing and kill the gun).
As we will be resetting the user data base, please see Nina or Lei if you
experience any problem logging on. We thank you for your cooperation and
for your patience during the past several difficult months as we tried to
fix this SEM.
How to become a certified SEM user? Please follow the FAQ link above or here for more details. Please contact Nina to arrange for SEM training and certification.
Why we don't need a lot of sample for SEM analysis? To our users with powder samples, we wish to remind them that one does not really need tons of samples to do SEM. Powders should be uniformly spread over a 1 mm x 1 mm area (in a layer a few microns thick) and attached securely onto the carbon tape. We definitely do not need powders spreading over an area larger than 1 mm x 1 mm and/or in a layer thicker than 10 microns. Here, we should remember: LESS is MORE, b/c: (a) A finely focussed electron beam (<10 nm dia.) hitting any sample (especially the "gassy" ones) at high energy will cause local heating/interaction that leads to rapid gas desorption, which will cause the filament (sitting at the EHT voltage) to arc (the filament will not survive above 5x10-9 mB). Field-emission filament will not be able to handle a lot of arcings like that, which will shorten its lifetime significantly. So, the less samples that one uses, the more stable is the machine. (b) Powder samples that are too thick (or not securely attached to the carbon tape) will also lead to partial charging. This is b/c the electron beam typically penetrates a few microns, creating secondary electrons that are finding their way to the carbon tape. If the sample is too thick, these secondary electrons stay inside the bulk and the sample will charge up, leading to bad images. (c) More samples in the chamber will lead to a poorer vacuum, and it will take a longer time to pump the system down to the acceptable operating vacuum condition. Less gas in the chamber and less gas desorption from the sample (as induced by the high-energy electron impact) will also improve image quality.
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TOOLSET & SERVICE
We offer pay-per-use service for both academic and industrial users at competitive rates, with our expert operators providing sample characterization measurement (and analysis). For a selected number of tools (e.g. SEM), we also provide training to allow the users to access the tools through a self-serve booking system. To submit samples for analysis, please fill in Form A (and Form B for University of Waterloo users) above, and contact the respective technical specialists. For all other enquiries and guided lab tours, please contact manager . |
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KNOWLEDGE BASE Inside look at LEO chamber | CORE RESEARCH aT WATLAB Research news to come... |
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26 Jan 2018 - New
beginning
Established
with funding support from Canada Foundation for Innovation and the
Province of Ontario in 1999, WATLab is the first multidisciplinary
materials research centre in Canada's Technology Triangle. WATLab
offers a complete toolset for advanced materials research and
emerging technology development. Most of our instrument systems are
state-of-the-art and some are unique in Canada, and they include:
OUTREACH