[mems-talk] Removing oxidised resist from gold surfaces

[Michael D Martin]

Hi, 
  Jeffrey, we have seen similar problems; particularly related to
plasma modified resist from DRIE.  We use long soaks in Aluminum etch
from Transene (containing Phosphoric, Nitric and Acetic Acids)  at
40-80C followed by a rinse in acetone to get all residues off.  

Good luck, 
   Michael Martin
   U. of Louisville


>>> "Yue Mun Pun, Jeffrey" <g0500396 at nus.edu.sg> 8/13/2007 6:06 AM >>>
Hi,
Due to the long time taken for Acetone at 70-80'C used to remove AZ9260
resist via lift-off, I have attempted to use Piranha (H2SO4:H2O2 = 3:1)
to remove some small amounts of resist remaining on my wafer surface
which has gold conductors patterned on it.  
However, after the Piranha treatment, I observed water-like droplets
remaining on the gold conductors, which I think are solubulized resist
that have been oxidized by the Piranha and stained on the gold surfaces.
 The SiO2 surface remains clean.  
Can anyone tell me how I can remove these 'resist droplets', which have
stained on the gold condutors?