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Step and scan exposure tools for 300 mm wafers are being introduced to more fabs aimed at volume production of semiconductor devices with sub 150 nm features. We have developed a KrF scanner for 130 nm applications, and an ArF scanner for the 110 nm generation. High NA, ultra-low aberration projection lenses developed for these tools provide imaging performance that meets requirements of the respective generations, with improved critical dimension (CD) uniformity and low distortion. These achievements have resulted from lens manufacturing that employs higher order Zernike coefficient lens tuning. The scanners incorporate a common platform designed to meet increasing accuracy requirements in 130 nm and 100 nm processes. Compared to previous models, the new platform reduces the impact of vibrations on the floor by receiving the stage drive reaction force with a structure of high damping capability. The wafer stage mounted on the platform simultaneously improves throughput and synchronization accuracy, through increased rigidity of its mechanism. A higher magnification alignment scope with shorter baseline is introduced to achieve high overlay accuracy. We also incorporate a new type focus sensor with self-thermal compensation functionality to improve focus-leveling performance. This paper explores the effects of moving standard deviation (MSD) upon CD uniformity and contrast, and proposes a measure to evaluate the effects on a quantitative basis. It also attempts to clarify synchronization accuracy budget for each technology generation, and introduces a new platform that can satisfy the accuracy required for the 100 nm generation and beyond. The proposed platform can remarkably enhance synchronization accuracy and throughput with wafer and reticle stages of high control performance and high-efficiency high-output linear motors. For this platform, we have developed a new mechanism that cancels the stage drive reaction force within the system and prevents it from being transferred to the floor. This paper shows that applying this system not only improves stage performance but also allows permissible vibration level of the floor to be considerably relaxed.
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