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How to remove chromium oxide

Hi experts,

My trouble is how to remove chromium oxide parts in a thin chromium film. I have tried HF, but cannot remove it.
The chromium film is very thin, about 20nm, so the oxide parts hardly can be detected. Only through microscope, it is seen that the color is different from chromium film.

For this case I think the adhesion between film and its oxide layer is too strong to remove oxide layer, but really hope somebody can tell me one solution.

By the way, is there any solution which can remove chromium film quickly?
Thanks a lot.

Lin Ying
data storage - Singapore
2003

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Chromium forms a very tenacious oxide very quickly and it is difficult to remove.
Your comment about it being only 20nm thick suggests you have a quite sophisticated interest in the surface, so I would suggest you remove it under vacuum, using a plasma discharge in an inert or reducing atmosphere.

Yes, even vacuums have an atmosphere! However, remember that as soon as the clean surface comes into contact with air, or any oxidizing atmosphere, it will rapidly regain its oxide film.
Consequently, once you have obtained your oxide-free surface, it must be kept under vacuum.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003

Dear All

I want to whether the occurrence of electrolysis effect is acceptable while copper pipe direct contact with stainless steel bracket on external wall.

Regards

Nicky Lam
property management and maintenance - Hong Kong
2004