If you are spinning onto an oxide, are you using HMDS ? This can remove some of the moisture and improve adhesion. I used to have a similar problem though I'm not sure if it is the same one your talking about.. I've never come accross the term 'mousebites'. Mike Rosa. At 08:21 2/04/98 -0600, you wrote: > Has anyone ever heard of this term. We are using it to describe a >problem we are having along an exposed region of photoresist where the >resist "pops" off leaving a semi-circle in the remaining pattern edge. >We are using a 5 minute vapor prime but we have seen the same problem at >lesser times so I dont think we are overpriming the wafers. You can >immediatly tell after exposure if mousebites are there as they leave a >bubbly area in some areas of the wafer which is visible to the eye >before develop. This problem does not occur every time (15-20%). Any >suggestions would be greatly appreciated. > >Please reply to phowell@i-o.com > >Regards, Pat Howell > > > >