With the full-scale adoption of EUV exposure tools, the use of Metrology and Inspection systems adapted for EUV process evaluation is increasing. In particular, with the increased durability of Pellicle, the importance of actinic Metrology and Inspection systems is increasing, and EUV light sources with high brightness and high availability are required. Gigaphoton Inc. has been developing laser-produced plasma (LPP) EUV light sources using Sn droplet technology for exposure tool since 2000. Based on this accumulated LPP EUV source technology, we have developed a High-brightness and compact LPP EUV source for Metrology and Inspection systems. This newly developed light source is a SoCoMo (Source Collector Module) EUV light source with a built-in reflective mirror based on customer specifications. In addition, it features stable operation and a one-year maintenance-free structure, contributing to longterm stable operation of the inspection equipment. Currently this EUV light source has demonstrated a brightness of 120W/mm2sr at the plasma point at a repetition frequency of 20kHz without any decrease in reflectivity of the EUV collector mirror after 500 hours of operation.
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