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  for Metal Finishing since 1989
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Etching aluminum leaving aluminum oxide

2006

I wanted a method for Etching aluminum without affecting aluminum oxide.
Can please tell me the way to do it?
It is very important for my research.

M.Gowtham
Student - Palaiseau, France

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Well, I'm sure it depends on what you want to do exactly, but I'm sure there are several things that eat aluminum but not the oxide. My first naive response would be HF or even just piranha (H2SO4 and H2O2). But it will depend on what your process is and what, exactly, you are trying to do. And, of course, you should never use these acids without proper knowledge of the dangers (especially HF!).

But a great series of papers, that lists several etchants and what they do and do not etch, was written by Kirt Williams and others:

Journal of Microelectromechanical Systems, Vol 5, No 4, p 256, 1996

and

Journal of Microelectromechanical Systems, Vol 12, No 6, p 761 2003

Brad Blakestad
- Boulder, Colorado, USA
2006