Kristjan, I'm not sure if that is correct. Negative tone resists work by becoming cross-linked (i.e., less soluble) when exposed to UV. So, the flood exposure process you described would just be re-exposing the regions that were already exposed the first time around (since the pattern is there due to the fact that it was exposed in the first round). Best Regards, Chad Brubaker -----Original Message----- From: Kristjan Leosson Subject: RE: [mems-talk] About Negative Photoresist You can use maN-490 from www.microresist.de for film thickness in the range 5-16um. Since it is a negative resist, you can use flood exposure on the final pattern and remove it with your standard developer. You can also use organic solvents.