Hey, all, We have a spin coating system (P-6708D) and I am trying to use it for SU-8 coating. The chuck diameter is 1 inch and the substrate is normal coverslip. It worked fine before, but recently, we got some problem with it. Even at low speed (500 rpm), the coverslip will be thrown away. It seems that the coverslip will not be held by the vacuum. I suspect the problem is with the vacuum. First, I checked the vacuum pump, which works fine. Then I checked the connecting tube, and there is no leaking. When I pressed the "start" botton, the system did not give error message. So I suppose the system is fine. Do you get similar experience? Any other places I can check and repair to make the system work? I appreciate your time very much. Thanks, Lina Wang Driftmier Engineering Center University of Georgia