Dear Jeffrey,

                 It is necessary to do plasma ashing in your procrss.I also got
the same problem.To strip PPR,you can directly for Piranha
(H2SO4:H2O2 = 3:1).

jaibir


On Fri, 10 Aug 2007 Yue Mun Pun,Jeffrey wrote :
>Hi,
>After I have patterned some gold conductors on SiO2 wafers and
>lifting-off the resist, I tried plasma treatment with the conditions
>250W, O2 plasma at 10sscm (171 mT) for 20-30mins.  It turned out that
>there were some resist being burned away and become blackened.  The
>blackened resist stringers remained on the gold conductors and these are
>very difficult to remove.  I have tried combinations of at 80-90'C for up to 1
hr, SC1 (NH4OH:H2O2:H2O =
>1:1:5) for 15mins as well as AZ300T resist stripper but all these are
>unable to remove the blackened resist stringers.
>
>After all these chemical cleans, the SiO2 surface is very clean but the
>gold conductors are still stained with the blackened resist stringers.
>
>Can anyone suggest how I could more effectively remove these resist
>stringers?  Thanks!
>
>Jeffrey


with regrads

Jaibir Sharma
Reasearch Scholar(PhD)
Electrical Department,
IIT Madras,
Chennai - 36
INDIA

Phone:044-22575444(off)
      09840396872(home)