selective etchants

[Lino1406]

I will be thankful for comments, additions on this table - selective etchants

 

[Owltech]

A good book on the subject:
https://vector.cnam.umd.edu/images/links/Handbook_of_Metal_Etchants.pdf

 

[Lino1406]

Thanks, I reviewed this, as well as other references

 

[geedigity]

Does:
N = Nil or no (won't dissolve)
Q = Quick or will dissolve readily
S = Slow to dissolve

You could also add (p) or (a)
Where:
Q(p) = Quick when in powder form
S(a) = Slow when in button, alloyed or solid (not powdered) form
Q(a) = Quick when in button alloyed or solid (not powdered) form
Thank you,

 

[Lino1406]

I appreciate your comment (feel free to build a more inclusive table). The table as is reflects more personal interests like separating palladium from copper, germanium and gallium arsenide semiconductors from gold.

 

[Yggdrasil]

Interesting.
A follow up on the ammonia peroxide leach for copper.

Will the ammonia smell make this an unwanted process to run?
According to a paper from Dicle University in Turkey it has high etchrate and works a bit like AP, it first forms cupric ammonium complex Cu(NH3)4²⁺ and then Cu(NH3)4²⁺ + Cu ---------> 2Cu(NH3)²⁺
before it reoxidize with oxygen from the air(air bubbler), which indicates that it can run like AP.
If I'm not mistaken it seems like it will not etch Sn which will make this process more targeted than AP.
Have anyone tried it or know more about this process?
How about toxicity and stability(explosive) of copper ammonia salts comparing to Chlorides?

Link to PDF paper Link to PDF paper from University of Dicle

Edit: Sorry for the long link, I might neeed a course for shrinking links ;-)
Edit again: Fixed link thanks to tips from FrugalRefiner

 

[FrugalRefiner]

See Including Links with Reader Friendly Titles

Dave