SPECS 2D-CCD, User Manual

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Manual V2.docx | Status 10.12.2015 | Version 1
Even if the analyzer casing just feels warm, any internal parts seated on insulators may still be too
hot for safe operation. All users should be aware of this issue and take the necessary precautions.
Vacuum conditions 2.2
Always observe the following points in order to protect the detector:
•
Avoid backstreaming from oil diffusion pumps or roughing pumps at all costs. When
using such pumps, you should use cold traps and molecular sieve traps. Make sure these
are correctly maintained.
•
Operate the detector in a clean vacuum environment of 5 × 10
−8
mbar or better in order
to ensure the longevity of the detecting surfaces. The detector can be degraded by
exposure to various types of hydrocarbon gases which raises the work function of the
surface and hence causes gain degradation.
•
Do not allow gases containing F, S and Cl to enter the detector area, as they may
decompose under electron bombardment.
Caution!
Do not operate the detector without a vacuum interlock. If high voltage is applied to the detector
while the chamber vents, all CEMs and MCPs will be irreparably destroyed.
Electrical connections 2.3
The wiring scheme for the 2D-CCD / 3D-VLEED Detector is complex and involves several power
supplies. To make the wiring scheme easier to understand, it is divided into two parts, which are
described in the following sections.
Please note these general points for the electrical connections and power supplies:
•
There is a ground screw on the rear of the power supplies which should be attached to a
central earthing point by a low resistance earthing strap.
•
The power supplies should be fitted into a rack or installed on a flat, stable surface.
•
Make sure the equipment is protected against high pressures by interlocks. Do not
defeat the interlocks during operation.
The 2D-CCD / 3D-VLEED Detector requires several power supplies for its operation:
•
Two SPECS HSA 3500plus units for the CCD detector and the rotator.
•
Three Focus units for the spin detector, evaporator and coil magnetization.
The following figures show all electrical connections for the 2D-CCD / 3D-VLEED Detector.