Abstract: Lithographic exposure is the key process in the manufacture of integrated circuit, and the performance of exposure system decides the level of microelectronic manufacture technology. In this paper, the present status and progress in 193 nm exposure system are described. The resolution enhancement technologies widely used in 193 nm lithography, such as offaxis illumination, phase shifting mask and optical proximity correction, are also introduced. By showing the composition and key technologies of the exposure system, the challenges in development of lithography instrument are discussed.