SPECS 2D-CCD, Руководство пользователя

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Manual V2.docx | Status 10.12.2015 | Version 1
6.10.4 Degassing the detector
During first use after bake out, rapid desorption of surface adsorbed gas will occur from the
walls of the channel electron multipliers, so care should be taken not to use the detector at
full channel electron multiplier voltage and full intensity within the first few hours of
operation.
We recommend increasing the detector voltage over a period of 1.5 hours up to the
recommended value. The full degassing procedure is described in Section 2.5.
6.10.5 Measurements
Measurements at the secondary electron cut-off needs special care. Use low pass energies
(3- 5 eV) and small slit settings to avoid possible degradation.
Handling MCPs 6.11
In the case of repairs or modifications that affect the MCPs, you should return the detector
to SPECS. If it is necessary for you to handle the MCPs yourself, you should observe the
precautions detailed below in order to prevent damage to the MCPs.
Shipping containers should be opened only under class 100 laminar flow cleanroom
conditions.
When handling MCPs, always wear clean, talc-free, class 100 clean-room compatible, vinyl
gloves. No physical object should come into contact with the active area. The MCP should be
handled by its solid glass border using clean, degassed tools fabricated from stainless steel,
Teflon or other ultra-high vacuum-compatible materials. Handling MCPs should be limited to
trained, experienced personnel.
MCPs without a solid glass border should be handled very carefully, taking great care to
touch only the outer edges of the plate. Please note that the MCP type used for the SPECS
CCD detector is extra thin (L/D = 50) because of their better imaging quality. Unfortunately
this MCP type is also extremely fragile.
The MCP should be protected from exposure to particle contamination. Particles stuck to the
plate can be removed by using the single-hair brush and bellows which is part of the CCD
detector package delivered by SPECS.
The MCP should only be mounted in fixtures designed for this purpose. Careful note should
be taken of any electrical potentials involved.