Three-component photoresists based on thermal crosslinking and acidolytic cleavage

Three vinyl ether monomers, 2,2-bis(4-[2'-(vinyloxy)ethoxy]phenyl(propane, 1,3,5-tris[2'-(vinyloxy)ethoxy]benzene, and 1,1,1-tris(4-[2'-(vinyloxy)etho xy]phenyl)-ethane were synthesized and studied as thermal crosslinking gent s in a three-component chemically amplified photoresist system. During preb ake the resists were completely insolubilized in aqueous base through therm al crosslinking between poly(p-hydroxystyrene) binder polymer and the vinyl ether monomers. Upon exposure to UV and subsequent postexposure bake, the crosslinks were cleaved by photogenerated acid, leading to effective solubi lization of the exposed areas. The thermal crosslinking and acid-catalyzed cleavage of the crosslinks were investigated by infrared (LR) spectroscopy. Degree of conversion of vinyl ether groups, dissolution rare and photosens itivity of the resists are strongly dependent on prebaking temperature. The resists showed relatively high sensitivity at 365 nm, and afforded positiv e-tone images by alkaline development. (C) 2000 Elsevier Science Ltd. All r ights reserved.