This Faraday cup is used for broad, off-axis charged particle beams which need to be focused and deflected in the right direction. It consists of a central electrode and four surrounding outer electrodes indicating the beam size and position in relation to the beamline center.
The 4 Sector Faraday Cup was developed for positioning of a charged particle beams. The particle beam current can be measured on a central electrode of a certain diameter as well as on four segments surrounding the central electrode indicating the beam size and position in relation to the beamline center. Thus, a broad, off-axis incoming beam can step-by-step be focused and deflected in the right direction. Hardware for charged particle current measurement as well as a read-out and display software are optionally available for this device.
Each sensitive segment of the 4 Sector Faraday Cup is electrically insulated inside the cup housing and has to be connected to an electrical vacuum feedthrough by a Kapton insulated wire. The cup housing itself can also be mounted onto an electrically insulating holder in case the current on the housing is supposed to be recorded. Furthermore, the cup setup includes a suppressor electrode to compensate secondary electron emission from the cup surfaces. The cup is made exclusively from materials suitable for ultra high vacuum conditions down to 1e-10 mbar.
Faraday Cup Parameters
central electrode diameter
2 mm, 5 mm, or customer-specific
diameter of entire sensitive area
20 mm or customer-specific
recommended supressor voltage
max. beam power without additional cooling
dimensions (length x width x height)
42 mm x 36 mm x 55 mm
max. bake-out temperature
from 1e-10 mbar up to atmospheric pressure
Scope of Delivery
4 Sector Faraday Cup incl. screws for wire attachment
linear vacuum feedthrough with manual or motor-driven positioning system
electrical feedthroughs and connection of cup inside a vacuum chamber via Kapton insulated wire
picoampere meter or electrometer for measurement of charged particle current or pulses