title: Estimating the dopant distribution in Ca-doped α-SiAlON: statistical HAADF-STEM analysis and large-scale atomic modeling.
abstract: We investigated the dopant distribution in Ca-doped α-SiAlON by using high-angle annular dark-field scanning transmission electron microscopy and a multi-slice image simulation. Our results showed that the electron wave propagated by hopping to adjacent Si(Al) and N(O) columns. The image intensities of the Ca columns had wider dispersions than other columns. To estimate the Ca distribution in the bulk material, we performed a Monte Carlo atomic simulation of the α-SiAlON with Ca dopants. A model including a short-range Coulomb-like repulsive force between adjacent Ca atoms reproduced the dispersion of the intensity distribution of the Ca column in the experimental image.
authors.affiliation: Laboratory of Integrated Function Materials, Center for Advanced Research of Energy and Materials, Faculty of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan sakaguchi@eng.hokudai.ac.jp.
authors.forename: Norihito
authors.initials: N
authors.lastname: Sakaguchi
authors.affiliation: Laboratory of Integrated Function Materials, Center for Advanced Research of Energy and Materials, Faculty of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
authors.forename: Fuuta
authors.initials: F
authors.lastname: Yamaki
authors.affiliation: Laboratory of Integrated Function Materials, Center for Advanced Research of Energy and Materials, Faculty of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
authors.forename: Genki
authors.initials: G
authors.lastname: Saito
authors.affiliation: Laboratory of Integrated Function Materials, Center for Advanced Research of Energy and Materials, Faculty of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kunisada
keywords: HAADF-STEM; Monte Carlo simulation; dopant distribution; electron channeling; multi-slice simulation; α-SiAlON