Loading Source Material

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• Always take a picture before pulling a cell to ensure correct orientation upon reinstall

Source Material Loading Table

Source Material Loading Procedures

Group III

• Group III ingot difficulties: Ga can melt from finger heat, Al is small and can be hard to get in the cell, In is sticky in the wrapper.

Ga

• Remember Ga forms a liquid eutectic with Al (UHV foil)-- don't let them come into contact.

• Ga is best to do at the beginning or end of the day. We don't want the Ga freezing before reload, so we can do it first and worry less about it melting and refreezing, or do it last and keep it warm the whole time.

• Ga ingots need to be kept refrigerated/cold. Loading Ga first means you can set up the ice packs and get the Ga done and the ice packs moved early on. Loading Ga last would make icepacks cumbersome for previous glovebag work, so it is ok to keep the Ga and icepacks in the fridge until it is time to reload Ga last. Put on the previous cell and before taking Ga off, setup the Ga ingots and icepacks and wait for 0.1% humidity.

• Ga icepacks are in the fridge freezer. Icepacks should be put in a plastic bag, wrapped in foil, then put under the glovebag.

• Ga ingots go in the glovebag on top of the icepacks.

• Ga (from cell) needs to be dumped into a plastic bin before being reloaded, and have large kimwipes underneath the bin (not foil).

• See Indium as far as putting ingots into the cell.

• Ga ingots can melt from finger heat, but working at a suitable pace will prevent this. Don't hold the ingots longer than necessary.

Al

• Normally, the Al cell must be removed from the system, put on the BOS, have a new crucible installed (Replacing Al crucible). Then you bake that new crucible, move the cell back to the GC, load the Al ingots, and reinstall. This has multiple procedures involved and takes multiple days.

• See Indium as far as putting ingots into the cell.

• Al ingots are small and more prone to not making it into the cell, i.e. falling and being unusable.

In

• To be elaborated upon?

• The Bravo In cell's capacity is 900 grams, but we fill it to much less than its full capacity because the cell sits a little below horizontal on the machine. A package of In contains 5 individually-wrapped ingots, so ~3 packages will typically be used.

• The reload process requires three people in the bag:

  • P1 using clean gloves to use clean scissors to cut open the clean In ingots (indiv.-wrapped) and shimmy the ingots into the crucible

  • P2 to cut open new ingot packages (dirty outside) and hold the package open so P1 can grab indiv.-wrapped In ingots (clean outside)

  • P3 to hold the cell and adjust its position based on what P1 needs to safely add material to the cell.

• Dropping the In into the cell is a delicate process. The first few ingots must be placed into the cell while the cell is mostly horizontal. This prevents the ingots from smashing into the bottom of the cell, causing crucible cracks.

• In ingots will be a little sticky in the wrapper, so be patient and wiggle the ingot out. The crucible lip can also help you gently apply pressure.

• The ingots must be loaded such that the source material only touches the crucible. If one of the ingots accidentally touches the top of the cell, which was arsenic coated, the ingot has to be thrown out so it would not contaminate the rest of the pure ingots already in the crucible.

• The ingots must be loaded such that the ingot wrapper and P1's gloves do not touch the ingots, crucible, or cell.

• Unused ingots should be kept in the outer baggie, wrapped in clean foil, and put back in the refrigerator with the rest of the In source material.

Open

Reloading Indium

• On 20170516, we refilled the cell with thirteen 23g ingots of 7N In (299g total). A package of In contains 5 ingots, so 3 packages were used.

Bi

• The Bi BBs are in a baggie in another baggie. The inner baggie is ultraclean.

• The loading responsibilities are the same as for In, i.e. the general who cuts and holds what

• P1, using ultraclean scissors, cuts a small opening in the inner ultraclean Bi containing baggie. The opening should be about 2-3 BBs large, and not cut all the way through the baggie (like for any cutting in the glovebag, always control and holdback the extra material/tail).

• Pour the tiny Bi BBs from the packet into the upright cell and gently shake cell as needed.

Group V

As

Pull with nipple to fit into transit case. Put giant foil bib in front of glovebag to help catch As debris

• Loading Arsenic Into Crucible

Sb

Pull with nipple to fit into transit case

• Loading Antimony Into Crucible

Rare Earth

Dopants

• Making Silicon and Beryllium

Pulling a Cell

• Always take a picture before pulling a cell to ensure correct orientation upon reinstall

Open

Pulling a cell