Abstract
New photoresist compositions containing tert-butyloxycarbonyl group protected C-4-hydroxyphenyl calix [4] resorcinarene molecular glasses and perfluorooctylsulfonate (PFOS) free photoacid generators (PAG) composed of a triphenylsulfonium aryloxyperfluoroalkylsulfonate was developed. The patterning performance of PFOS free photoresist compositions was examined using extreme ultraviolet (EUV or 13.4 nm) lithography and compared with photoresist compositions containing conventional perfluorobutanesulfonate (PFBS) PAGs. Features as small as 30 nm with low line edge roughness (LER) were readily obtained for both formulations. The non-PFOS photoacid generator forms acid that contains fewer fluorine atom than found in PFOS or in PFBS. The newly developed non-PFOS PAGs may find application in chemically amplified resists that address the environmental concerns raised by the widely used PFOS containing PAGs.
