Scanning electron microscopy (SEM) is generally used for line edge roughness (LER) measurement; however, it is difficult to achieve high precision LER measurement of photoresist due to shrinkage caused by electron-beam (EB) exposure. We have developed a metrological tilting-atomic force microscopy (AFM), which has a tip-tilting mechanism to measure vertical sidewall. In the last conference, SPIE-AL-2023, we demonstrated quantitative evaluation of shrinkage of ArF photoresist due to EB exposure by measuring the pattern before and after EB exposure [Kizu et al., Proc. SPIE 12496, 1249605 (2023)]. In this study, we will demonstrate quantitative evaluation of shrinkage of EUV photoresist due to EB exposure by the AFM technology.
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