title: Three-dimensional observation of SiO2 hollow spheres with a double-shell structure using aberration-corrected scanning confocal electron microscopy.
abstract: Optical sectioning using scanning confocal electron microscopy (SCEM) is a new three-dimensional (3D) imaging technique which promises improved depth resolution, particularly for laterally extended objects. Using a stage-scanning system to move the specimen in three dimensions, two-dimensional (2D) images sliced from any plane in XYZ space can be obtained in shorter acquisition times than those required for conventional electron tomography. In this paper, a double aberration-corrected SCEM used in annular dark-field mode was used to observe the 3D structure of SiO(2) hollow spheres fabricated by a carbon template method. The double-shell structure of the sample was clearly reflected in both XY- and XZ-sliced images. However, elongation along the optical axis was still evident in the XZ-sliced images even when double aberration correctors were used. Application of a deconvolution technique to the experimental XZ-sliced images reduced the elongated shell thicknesses of the SiO(2) sphere by 40-50% and the selectivity of information at a certain sample depth was also enhanced. Subsequently, 3D reconstruction by stacking the deconvoluted slice images restored the spherical surface of a SiO(2) sphere.
authors.affiliation: Materials Science and Engineering, Saitama Institute of Technology, 1690 Fusaiji, Fukaya, Saitama 369-0293, Japan. zhang.xiaobin@nims.go.jp
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Zhang
authors.forename: Masaki
authors.initials: M
authors.lastname: Takeguchi
authors.forename: Ayako
authors.initials: A
authors.lastname: Hashimoto
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Mitsuishi
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.forename: Peter D
authors.initials: PD
authors.lastname: Nellist
authors.forename: Angus I
authors.initials: AI
authors.lastname: Kirkland
authors.forename: Meguru
authors.initials: M
authors.lastname: Tezuka
authors.forename: Masayuki
authors.initials: M
authors.lastname: Shimojo