Characterization of Ion Beam Induced Nanoripples by Using Extreme Ultraviolet Synchrotron Radiation

Quasi-periodic nanostructures induced by ion bombardment (IB) on solid surfaces are characterized by small periods (10-100 nm) and large areas. Quasi-periodic nanoripple structures with the transverse feature size of around 100 nm and the gradually significant transverse periodicity and longitudinal continuity were fabricated on antireflection coatings by Argon-IB. To improve the characterization area, the morphological characteristics of the self-organized nanoripples were characterized by using extreme ultraviolet (EUV) scatterometry. The results show that in terms of samples, their transverse and longitudinal morphological features obtained by the in-plane and conical mode of the EUV scatterometry are in agreement with those obtained by atomic force microscope. These results demonstrate that the proposed method is feasible to characterize the basic morphological characteristics of quasi-periodic nanoripples and can provide a basis for subsequent quantitative analysis. In addition, the characterization area of self-organized nanoripple structures has reached an order of the mm(2) by EUV synchrotron radiation, and the characterization range of the Metrology Beamline of Hefei Light Source is extended to self-organized nanostructures, which can provide a reference for future studies on the scattering characterization of EUV lithography masks.