How to: Remove Outgassing Residues from Storage Semiconductors

Q. Which cleaner is best for removing alcohol and other outgassing residue from storage of semiconductors and related high purity components in plastic bags?

A. Semiconductors and related high purity precision manufacturing components are sometimes stored in bags during processing. Those bags can sometimes have plasticizers, plasticizer residues, or residues of cleaners used to clean the bags.

To remove those residues you need either a good high emulsifying cleaner or a good solvating cleaner. For immersion cleaning, it is more efficient to use an emulsifying cleaner if that cleaner is compatible with your semiconductor substrate. Many emulsifying cleaners contain metal salts, particularly sodium salts that would be incompatible with many silicon semiconductors.

If you are cleaning less sodium sensitive semiconductors then you can use a high emulsifying cleaner like Liquinox to remove organic residues such as alcohols and alcohol derivatives such as cleaner or plasticizer residues from plastic bags. Typically you might use a warm 1% solution of Liquinox in a soak or ultrasonic tank.

If you cannot tolerate sodium residues, then you would use a cleaner that relies on solvation like Detergent 8. Detergent 8 does not contain sodium. Of course since solvation is a less efficient process than emulsifying, you have to use higher concentrations of Detergent 8 to achieve cleaning. Typically you would use a 3-5% concentration of Detergent 8 to soak or ultrasonic clean with.