High accuracy cross-sectional shape analysis by coherent soft x-ray diffraction

摘要

When the scatterer size is less than 100 wavelengths, the effect of diffraction is large. The analysis of diffraction is important for 3D shape measurement. However, in soft x rays, shapes suitable for rigorous diffraction analysis have been limited to ellipses and periodic structures. We have developed a method to expand this to any shape (isolated triangle, rectangle, etc.). Experimentally, we measured the respective widths of the cross section of a column consisting of two layers and showed that the resolution was at least a few wavelengths. For this purpose, we have also developed a fast simulation method with a small memory size. (C) 2020 Optical Society of America