3 minimizing noise pickup from external cabling – INFICON Cygnus 2 Thin Film Deposition Controller User Manual
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Cygnus 2 Operating Manual
In many cases, a braided ground strap is sufficient. However, there are cases when
a solid copper strap (0.030 in. thick x 1 in. wide) is required because of its lower RF
impedance.
Figure 2-3 System grounding diagram
2.2.3 Minimizing Noise Pickup From External Cabling
When a Cygnus 2 is fully integrated into a deposition system, there can be many
wire connections, each a potential path for electrical noise to reach the inside of the
Cygnus 2. The likelihood of these wires causing a problem can be greatly
diminished by adhering to the following guidelines.
Use shielded coax cable or twisted pairs for all connections.
Minimize cable lengths.
Avoid routing cables near areas that have the potential to generate high levels
of interference. For example, large power supplies such as those used for
electron beam guns or sputtering sources can be a source of large, rapidly
changing electromagnetic fields. Placing cables as little as one foot away from
these problem areas can significantly reduce noise pickup.
Be sure that a good ground system and straps are in place per the
recommendations in
Ensure that all Cygnus 2 covers and option panels are in place and tightly
secured with the provided fasteners.
NOTE: Always use shielded cables when making connections to the Cygnus 2
rear panel to minimize electrical noise pickup.
Back Panel
Ground
Stud
Earth
Ground
Transducer
Feedthrough
Vacuum System