I am using a positive photoressit AZ P4620 for making a soft mask on glass slide. Usage of HMDS is not assuring me a good adhesion of photoresist on glass surface. The photoresist is getting etched in 5 min after I keep the slide in concentrated HF. My main aim is to get 20u microchannel in the glass slide. Which procedure will guarantee me a strong adhesion which can make the photoresist soft mask to withstand concentrated HF for 30 min?. The thickness of my photoresist soft mask if 6.5u. -- RUPESH SAWANT Biomedical Engineering, The University of Akron, USA. Tel: 330.338.8546