The process flow of the proposed cross-sectional measurement on EB induced PR-pattern shrinkage is shown in Fig. 2. First, a SEM is used to irradiate the EB on part of the PR line patterns to intentionally cause shrinkage. This SEM EB irradiation is denoted simply as “EB irradiation” hereafter. This does not mean the EB irradiation during the STEM observation performed afterward. Second, ALD is used to deposit a 2-nm thick thin film on the sample. The sample surface is thus conformally coated with a thin film. In the process, tetrakis(ethlmetylamino)hafnium and were used as precursors, the number of cycles was 14 and the process temperature was 80°C. Third, the sample is coated with amorphous carbon and tungsten layers to prevent pattern collapse during the following focused ion beam (FIB) process. Also during the process, the temperature was kept below 80°C in order to avoid thermal damage to the PR patterns. Fourth, a thin-film sample for the STEM observation is cut out by using a microsampling technique with a FIB. Finally, a cross-sectional Z-contrast image of the patterns is obtained by using a STEM with a 200-kV accelerating voltage. The thin film improves the Z-contrast at the pattern edge. As a result, the cross-sectional feature with a bright thin band, which corresponds to the PR pattern surface, is clearly shown in the image. The contour of the pattern is defined as the center of the bright thin band to further quantitatively evaluate the pattern shape.