FEI Quanta FEG 250, User'S Operation Manual

Page: 141 / 228

Maintenance and Troubleshooting: Gaseous Detectors
8-9
Gaseous Detectors
CLEANING THE GSED / LFD
FIGURE 8-6 REMOVING THE GSED ASSEMBLY
1. Vent the chamber.
2. Pull the end of the GSED detector head down to remove it from the
standard insert. The insert will remain inside of the pole-piece.
3. Pull the GSED pin contact board out of the signal connector
mounted to the chamber ceiling.
The PLA is part of the GSED detector and can be cleaned by inserting
a toothpick (or something similar) into the hole. The signal ring is
permanently attached to the underside of the detector, and can be
cleaned in a similar way.
CLEANING THE GBSD
1. Perform steps 1 and 2 above to remove the GBSD printed circuit
board from the chamber.
2. The GBSD is easily cleaned with a toothbrush, Soft Scrub/CIF
cleaner and water, as with the GSED. To access the PLA and
converter plate, remove the two screws holding the collector grid to
the printed circuit board. Scrub the SE grid gently, as this can be
easily damaged.
FIGURE 8-7 DISASSEMBLING THE GBSD