hi mikas

i have faced the same problem before.

1) if there is peeling at the time of wire bonding then its due to Au-Ti
interface problem. In this case you will have to bake the substrate in
vacuum prior coating the gold. I tried at 125 C for 2 hr. It reduces the
problem.

2) It will be better if you do adhesion test on gold before going to wire
bonding.

3) If its work at adhesion test, then you should increase the gold
thickness.  IT always difficult to do wire bonding on thin old layer.

best of luck
-Abhay Joshi
University of Pune, India.