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--- ebeam_filament [2021/01/29 11:25] – carlyfengel
+++ ebeam_filament [2021/01/29 11:41] (current) – carlyfengel
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 ====== Changing the ebeam filament ======
-|Introduction              |We have a Varian e-Gun 980-0003, powered by the e-Gun Control Unit Model 922-0020. Read the manuals FIRST before working on the instrument. They are short and informative. However the information about changing the filament (in the e-Gun Manual) is a little confusing, and we ended up successfully completing this task using our own method. This guide will explain the steps for how we changed the filament. You'll need several small Allen keys, some flathead screwdrivers, and 0.01" and 0.04" feeler gauges.|
+|Introduction              |We have a Varian e-Gun 980-0003, powered by the e-Gun Control Unit Model 922-0020. Read the manuals FIRST before working on the instrument; {{::ebeam:e-Gun Evaporation Source Manual.pdf|here is the e-Gun manual}}, and {{::ebeam:e-Gun Source Control Unit Manual.pdf|here is the Control Unit manual}}. They are short and informative. However the information about changing the filament (in the e-Gun Manual) is a little confusing, and we ended up successfully completing this task using our own method. This guide will explain the steps for how we changed the filament. You'll need several small Allen keys, some flathead screwdrivers, and 0.01" and 0.04" feeler gauges.|
-|{{ebeam:ebeam1.jpg?1000|}}|Here's what you see when looking at the e-gun and crucible holder from the front. The filament is around the back (you'll need to remove both sheet metal walls from the chamber to reach it).|
+|{{ebeam:ebeam1.jpg?2000|}}|Here's what you see when looking at the e-gun and crucible holder from the front. The filament is around the back (you'll need to remove both sheet metal walls from the chamber to reach it).|
-|{{ebeam:ebeam8.jpg?1000|}}|Here's behind the crucible holders. The filament is the curly piece of metal. To change the filament, we'll need to remove the filament, the two ceramic blocks holding the filament legs, and the cathode shield together as a unit. Before we do this, we'll need to disconnect the voltage leads from the filament. Before unscrewing anything, UNPLUG the e-Gun control unit!|
+|{{ebeam:ebeam8_2.jpg?1000|}}|Here's behind the crucible holders. The filament is the curly piece of metal. Each leg is secured in one of the blocks.|
 |{{ebeam:ebeam3.jpg?1000|}}|Here's the diagram from the manual showing the various parts. The filament is the cathode, while the crucible and crucible holder are the anode.|
-|{{ebeam:ebeam4.jpg?1000|}}|The voltage leads are shown here. There are two set screws, one on each side of the blocks, holding them to the filament. These can be unscrewed to loosen them from the filament and blocks. Then go to the other end of the voltage leads to loosen them, where they go out of the chamber. (next picture)|
+|{{ebeam:ebeam4.jpg?1000|}}|**Before doing any work on the instrument, unplug everything!** To change the filament, the first step is to disconnect the voltage leads (shown here). There are two set screws, one on each side of the blocks, holding them to the filament. These can be unscrewed to loosen them from the filament and blocks. Then go to the other end of the voltage leads to loosen them, where they go out of the chamber. (next picture)|
 |{{ebeam:ebeam5.jpg?1000|}}|Here the labeled screws can be loosened (but don't remove them) to allow the voltage leads to move slightly so they can be maneuvered out of the blocks.|
-|{{ebeam:ebeam6.jpg?1000|}}|Once the leads are removed, we can unscrew the two large screws shown here. Partially unscrew the left screw first, and remove the "wing". Then proceed to unscrew it the rest of the way, followed by the right screw. The blocks, filament, and cathode shield will come off together as a set (careful not to drop them!)|
+|{{ebeam:ebeam6.jpg?1000|}}|After the leads are removed, we'll need to remove the filament, the two blocks holding the filament legs, and the cathode shield together. Partially unscrew the left screw first, and remove the "wing". Then proceed to unscrew it the rest of the way, followed by the right screw. The blocks, filament, and cathode shield will come off together as a set (careful not to drop them!)|
 |{{ebeam:ebeam7.jpg?1000|}}|This is what it looks like. Place on a clean beta wipe. The filament is held in place by the upper two set screws, which can be loosened to allow the filament to be removed.|
 |{{ebeam:ebeam2.jpg?1000|}}|This is what the setup looks like with the filament and blocks removed. The giant metal U underneath is the magnet. The magnetic field extends up through the vertical pieces of metal separating the crucible cavities. The blocks holding the filament screw into the ceramic tubes in the center of the magnet.|