[mems-talk] Nickel wet etchants and selectivity with AZ9235 resist

[Pradeep Dixit]

Hello All,

I would like to seek advice from you.

I would like to etch 300 nm thick Nickel pattern without significant
undercut using 1:1:1 mixture of HNO3: H3PO4: DI water. Mask would be a
resist mask 2-3 µm AZ9235.

Does any one has idea about the selectivity of sputtered nickel with AZ9235
photoresist with this etchant?

I learnt that nickel can also be etched by Piranha solution (4:1 mixture of
H2SO4:H2O2) or by 30%FeCl3, or by Alumnium etchant etc. Has any body tried
it and can share the results and what masks .

Any suggest would be welcome

Thanks,
Pradeep