The capability of measuring cross-sectional profile for hole patterns in nanoimprint templates using small-angle X-ray scattering

Nanoimprint lithography (NIL) is one of the highest potential candidates for next generation lithography in semiconductors. NIL is very useful technology for pattern fabrication in high resolution compared to conventional optical lithography. NIL technology makes use of replication from quartz templates. The cross-sectional profile of the template is directly transferred to the resist profile on a wafer. Accordingly, the management of the cross-sectional profile on the template pattern is much more important than on each photomask. In our previous report, we had studied the performance of measuring cross-sectional profiles using grazing-incidence small-angle X-ray scattering (GISAXS). GISAXS has made it possible to analyze the repeated nanostructure patterns with a 2D X-ray scattering pattern. After various researches, we found the application is very effective in the method of cross-sectional profiling of sub-20 nm half-pitch lines-and-spaces (LS) patterns. In this report, we investigated the capabilities of measuring cross-sectional profiles for hole patterns using GISAXS. Since the pattern density of hole patterns is much lower than that of LS patterns, the intensity of X-ray scattering in hole measurements is much lower. We optimized some measurement conditions to build the hole measurement system. Finally, the results suggested that 3D profile measurement of hole pattern using GISAXS has sufficient performance to manage the cross-sectional profile of template. The measurement system using GISAXS for measuring 3D profiles establishes the cross-sectional profile management essential for the production of high quality quartz hole templates.