I've read HMDS doesn't always work for SU-8 but baking post HMDS
spinning can improve the situation.
(see this excellent website for more details:
http://memscyclopedia.org/su8.html ).
You should consider the following in your process:
1. Increasing your exposure dose. You generally need much more that
the datasheet values for best adhesion.
2. Make sure you ramp up and down during PEB.
3. Do you really need the hard bake? This can actually increase the
likelyhood of delamination.


On Mon, Aug 4, 2008 at 19:43, Jose Guevarra  wrote:
> I did try HMDS and that seems to work fairly well.
>
> Thanks.
>
> Oakes Garrett wrote:
>>
>> You should try the SU-8 adhesion promoters that are on the market.  MCC
>> and Silicon Resources in Chandler Arizona both have products that work
>> well.  What type of wafer are you using?
>>
>> Best Regards,
>>
>> Garrett Oakes
>