Hi Shib, The SU-8 2000s developer is PGMEA. This PGMEA is the solvent in AZ4620 that you expel by its soft bake. If you cannot replace SU-8 by another resist (eg AZ125nXT or photostructured PDMS) you could replace the sacrificial layer: just electroform your sacrificial layer and finally etch the metal. We do this with copper sacrificial layers. Regards Felix On 20:59, Shiv GD wrote: > Hello Everyone, > > I am working on a Microchannel device, and facing some problem with AZ 4620 > and SU-8 Layer. The device is fabricated on a glass substrate and I am > using AZ 4620 as sacrificial layer ( I need ~20um height). I patterned the > AZ layer using standard lithography process ( Spincoat, Bake on Hotplate > for 2mins @ 110'C, Expose and Develop using AZ 400K. ) and I want to keep > it until the last step. I than, spincoat SU-8 2025 (on top of the AZ 4620 > layer), bake, expose, post bake. But when I try to develop the SU-8 > structure ( using Microchem SU-8 developer ), I observe that the SU-8 > structure develops alright but the AZ sacrificial layer is gone. As a > result the SU-8 structure collapse, cracks and I can't continue to the next > step. > > What do you think I can do to resolve the situation ? Please suggest. > > Your help is much appreciated. > > Thank you. > > Shib >