Paul,

As my experience on SU-8, thermal shock is one reason for peeling off. I
don't know about BPR100, but it might be the cause.

Yifan

On Thu, Feb 11, 2010 at 8:47 PM, Paul Nguyen wrote:

> Hello everyone,
>
> I haven't seen this phenomenon but last couple of days 2 incidents have
> made
> me wonder about the cause.  My wafer with 35um thick negative resist was
> peeled off as a sheet after develop.  Anyone has any ideas of the causes?
> More info: the wafer was SB with 2mins/67C and 8mins/125C, exp and PEB at
> 5mins/90C then develop; the wafer was cleaned and hydrophilic before
> coating. Resist is BPR100.
>
> Thanks in advance for any hints.
>
> Regards,
>
> Paul