Haze And Sun For Mask Symposium

摘要

Ever since lithographers began exposing with 193nm DUV light, photomasks have accumulated photochemical haze that eventually congeals into crystalline defects. At this year's SPIE Symposium on Photomask Technology (October 6-10 in Monterey, CA), maskmakers learned that clearing off the haze uncovered something new: a "sun effect" where images appeared brighter (and clear CDs bigger) in the center of the reticle, with dimmer regions at the edge. Perhaps symbolically, the days in Monterey began with thick haze, progressed to bright sun, and ended in darkness.