Developing the electron tomography for correct reconstructions of three-dimensional shape and density of materials based on elucidation of the multiple scattering phenomenon of electron beams

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H02600
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 29020:Thin film/surface and interfacial physical properties-related
• Research Institution: Osaka University
• Principal Investigator: Yamasaki Jun 大阪大学, 超高圧電子顕微鏡センター, 教授 (40335071)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 電子線トモグラフィー / 密度定量 / 多重散乱 / 非線形強度減衰

Outline of Final Research Achievements

Manufacturing a whole-angle-tilt sample holder, developing a mounting technique for submicron-sized samples, and devising a new mutual alignment algorithm for a tomographic tilt series were achieved for high-precision reconstructions of three-dimensional (3D) shapes of samples. Moreover, based on the precise measurements for the nonlinear relationship between material’s thickness and image intensity in electron micrographs, the procedure of correcting the nonlinearity in experimental images including noise was established. Integrating all the achievements, the method to obtain correct 3D density of materials by electron tomography, which is the purpose of this project, was successfully established.

Free Research Field

電子顕微鏡学

Academic Significance and Societal Importance of the Research Achievements

長年にわたり物質厚さと電子顕微鏡像強度の関係式が未解明であったが、電子顕微鏡の２大観察方式であるTEM像もSTEM像も数式で表せることになり、高エネルギー電子の多重散乱過程の理解につながる学術的意義のある成果が得られた。また汎用電子顕微鏡の観察スケール(ナノメーター)とX線による観察スケール（マイクロメーターからミリメーター）をつなぐサブミクロンスケールの物質の三次元構造を高精度に観察できるようになったため、そのサイズの物質群を活用した科学技術や応用技術への貢献が期待できる。