Development of a F/sub 2/ laser with high repetition rate for optical lithography below 100-nm node

Summary form only given. The molecular fluorine lasers (F/sub 2/ lasers) are expected to be applied to optical lithography at design rule below 100 nm for future 4 Gbit dynamic random access memory. One of the most important F, laser requirements for the steppers/scanners is a stable operation at a high repetition rate of multi-kilohertz. In order to avoid damages of optical materials and coatings due to high photon energy of 7.9 eV of F/sub 2/ laser and to provide a sufficient radiation power to wafers, higher repetition rate is required to increase the laser average power instead of increasing the laser one-pulse energy.