Optical lithography is one of the most fundamental technologies for 0.18micrometers development. At tighter critical dimension (CD) control and stringent design rules are required, 248nm DUV step and scanner exposure tool becomes major equipment for 0.18micrometers lithography process because of its tighter CD and overlay control and better image quality. Meanwhile, various types of advanced chemical amplified photoresist which have been designed for 0.18micrometers geometry are also available for R and D purpose or prototype usage. In this paper, we present here the evaluation result of ASML 5500/500 step and scanner system for 0.18micrometers line and space and contact hole with Shipley's new photoresist UV70 and UV90. Different NA/PC settings for both conventional and annular illuminations were selected to test on process margins, iso and dense bias and CD uniformity. Optimum NA/PC settings were obtained for 0.18micrometers design rules. The results showed that with new resist UV70, UDOF of larger than 0.60micrometers was achievable at the optimum NA/PC setting for 0.18micrometers line and space. With new resist UV90, UDOF of 1.1 micrometers can be obtained for 0.22micrometers dense contact hole. Furthermore, as a comparison study, inorganic oxynitride (SiON) BARC and new generation organic BARC are applied separately to suppress swing ratio and substrate reflectivity. The UDOF for inorganic BARC is slightly larger than organic BARC process. The advantage of conformability in SiON BARC gives better pattern transfer CD control. In summary, step and scan system with new photoresist can extend photolithography technology to 0.18micrometers with manufacturable process.