Roger H. French, Jerald Feldman, Fredrick C. Zumsteg, Michael K. Crawford, Andrew E. Feiring, Viacheslav A. Petrov, Frank L. Schadt III & Robert C. Wheland, DuPont Co., iTechnologies and Central Research and Development, Wilmington, DE, USA; Joseph Gordon & Edward Zhang, DuPont Photomasks Inc., Danbury, CT, USA

Substantial progress has been made in developing novel fluoropolymer materials for 157nm lithography. Materials with sufficient transparency at 157 nm to enable both thick single layer resists and high transmission pellicle membranes have been demonstrated. We have shown that tetrafluoroethylene (TFE)-containing 157 nm photoresist binder resins can be made that are sufficiently transparent to be used at film thickness greater than 200nm, have good photosensitivity, exhibit low outgassing upon exposure, are compatible with aqueous base development, and have etch rates comparable to PHOST resins. Optical absorbance on the order of 1.5/µm @ 157 nm should be possible for photoresits.