Hah, I've used 1:1 and it worked fine for me so yeah, any background
people can shed on this would be interesting to say the least.

Nicolas Duarte
PhD Candidate under Dr Srinivas Tadigadapa
Penn State University

At 12:20 PM 3/1/2007, you wrote:
>Hello,
>I need to use piranha solution (H2SO4 + H2O2)
>to clean my wafers after etching, but it's not clear to
>me what is the best ratio in solution between these two
>chemicals to have optimal removal of resist and post etch
>fluoropolymers.
>In the literature I found H2SO4:H2O2 as 2:1 or 3:1 or even 6:1.
>Sometimes there is water dilution. On the other hand they
>never explain why they choose these ratios...
>Has anybody of you some knowledge about this?