Resist Systems Utilizing Chemical Amplification

Chemical amplification processes have been reported to be useful in the development of sensitive high resolution photoresists. Acids photochemically generated from onium salt precursors catalytically remove a protective group from substituted hydroxystryene polymers. Nonionic, acid precursors based on o-nitrobenzyl ester photochemistry have been developed that also have utility in resist applications. Several resist systems capable of imaging via chemical amplification processes have been evaluated in terms of their materials and lithographic properties. Resists with sensitivities ranging from ~ 15 to 150 mJ/cm sup 2 in the deep-UV region have been prepared and 0.5 micron resolution has been demonstrated.