you mis-typed the thickness....you have 5-8mm which requires x-ray. You meant 5-8 um. Craig -- Craig Friedrich, PhD, PE Professor of Mechanical Engineering Director, Multi-Scale Technologies Institute Dept. of Mechanical Engr. - Engr. Mechanics Michigan Technological University 1400 Townsend Drive Houghton, MI 49931 phone: 906-487-1922 fax: 906-487-2822 > Hello all, > > I want to expose(crosslink) 950K A1 PMMA (Thickness of about 5-8mm) from > Michrochem (suggested parameters by michrochem : doses >500mJ/cm2 at peak > wavelength of 248nm). > But the aligner I am using does not have UV/X-ray capabilities, Has anyone > encountered such problem?. Especially with such thick PMMA layer. What are > my options? I was thinking of using an external exposure UV-C source. > > Any help in this regard will be grately appreciated.