Etching SnO2 Thin Films: Advice Needed

[dtgiang]

Please, give me some advices on how to etch SnO2 thin films.
For wet etching, I tried HCl (5%), NH3Cl, and HF. They seem to not etch SnO2 or the time I put the SnO2 in the solution was too short (<5 mins).
I used RIE with CHF3/Ar to etch SnO2. The RIE worked but the etching rate was so slow, 1-2 nm/mins. I tried to increase the RF plasma power 100, 150, 200 W and the CHF3/Ar gas ratios but the etching rate seemed to be the same.
Many thanks in advance.

 

[DrDu]

Maybe you should have a look at a chemistry book, like Gmelin?
SnO2 is very inert. Maybe you could try some concentrated alkali solutions (NaOH or KOH).

 

[dtgiang]

Thanks DrDu.

If you have some experiences in etching SnO2 with NaOH/KOH, could you, please, share your experiences or give me some literature on that?

Regards,