High-resolution low-shrinkage CD metrology for EUV resist using high voltage CD-SEM

A CD-SEM metrology for an EUV resist that was compatible with low shrinkage and high spatial resolution was investigated by using primary electrons (PEs) with high energy. The shrinkage and an image sharpness were evaluated for the EUV resist using PEs with energies of 200, 800, and 4000 eV. As a result, the smallest shrinkage and image sharpness were obtained under the condition of PEs with an energy of 4000 eV. We believe that a high-voltage CD-SEM is a potential candidate for CD metrology tools in the EUV lithography era.