EB defect inspection of EUV resist patterned wafer for hp 32 nm and beyond

It is important to control the defect level of the EUV lithography mask because of pellicle-less. We studied the resist patterned wafer inspection method using EB inspection system. In this paper, the defect detection sensitivity of EB inspection system is quantified using hp 32 nm line and space pattern with about 5 nm LWR (Line Width Roughness). Programmed defects of 13 nm narrowing and 10 nm widening have been detected successfully after the optimization of column and inspection condition. Next, the defects detected by mask inspection system and EB wafer inspection system were compared and were in good agreement for printed killer defects. In these results, EB inspection system is proved to be useful for EUV resist inspection. Further, we evaluated the resist material damage by EB inspection irradiation and indicated the direction of reducing the shrinkage.