PHOTOGENERATED BASE IN POLYMER CURING AND IMAGING - CROSS-LINKING OF BASE-SENSITIVE POLYMERS CONTAINING ENOLIZABLE PENDANT GROUPS

The ability of photogenerated amine catalysts to effect the insolubili zation of polymers containing acidic methylene units is explored. Cros s-linking of films of poly(2-acetoacetoxyethyl methacrylate)-co-(methy l methacrylate) or poly(2-cyanoacetoxyethyl methacrylate)co-(methyl me thacrylate) containing [[(2,6-dinitrobenzyl)oxy]carbonyl] cyclohexylam ine as photobase generator and a bifunctional aldehyde molecule can be achieved upon exposure to deep-UV irradiation and subsequent heating. Polymers containing the cyanoacetate functionality displayed high res ist sensitivities (ca. 20 mJ/cm(2)) in simple contact imaging experime nts. Monitoring of the resist films using UV-vis spectroscopy suggeste d that crosslinking of the polymers in the presence of the aldehyde mo iety proceeds via a Knoevenagel reaction. Photo-cross-linking and imag ing can also be achieved in the absence of the added acceptor molecule and possible mechanisms for this insolubilization are discussed. Inco rporation of the reactive cyanoacetate functionality into a phenolic p olymer to provide aqueous base development is examined via the synthes is of -cyanoacetoxymethyl)styrene]co-[4-hydroxystyrene].