Plasma and Fusion Research

Volume 14, 3402049 (2019)

Regular Articles

Characterization of He Induced Nanostructures Using SEM Image Analysis
Hirohiko TANAKA, Shin KAJITA1) and Noriyasu OHNO
Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan
Institute of Materials and Systems for Sustainability, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan
(Received 26 December 2018 / Accepted 3 February 2019 / Published 10 April 2019)


Helium induced nanostructures on tungsten were characterized by applying basic statistical analysis techniques to scanning electron microscope (SEM) images. As the analysis targets, pinhole- and fuzz-dominant surfaces irradiated with different ion fluences were employed. Although two-dimensional Fourier analysis of the normalized brightness of SEM images clarified several characteristic features, their differences are small to distinguish the dominant nanostructures. On the other hand, probability density functions (PDFs) of the normalized brightness indicate that hole- and fuzz-dominant surfaces have long tail and Gaussian-like shape, respectively. By using several indexes with considering the black and white saturation, it was found that kurtosis and Kullback-Leibler divergence could provide reasonable judgement as the characterization index.


image analysis, statistical analysis, SEM, two-dimensional fast Fourier transform, probability density function, kurtosis, Kullback-Leibler divergence, pinhole, fuzz

DOI: 10.1585/pfr.14.3402049


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