Indexed by:Journal Papers

Date of Publication:2019-11-01

Journal:OPTICS AND LASERS IN ENGINEERING

Included Journals:SCIE、EI

Volume:122

Page Number:347-353

ISSN No.:0143-8166

Key Words:High-resolution transmission electron microscope; Digital rotation moire; Strain measurement; Grating rotation angle; Fringe inclination angle

Abstract:This study presented a digital rotation moire (DRM) method for strain measurement based on high-resolution transmission electron microscope (HR-TEM) lattice images. The TEM lattice images were used to generate the reference and specimen gratings. The procedure involved in the proposed DRM method was based on the rotation moire principle and a digital moire algorithm, which detect the in-plane strain components by quantifying the image parameters, including the mean value of the relative rotation angles between the specimen and reference gratings and the fringe inclination angle in the digital moire patterns. The obtained strain is the strain of the lattices in the analysis area relative to that of the lattices in the reference region. A series of virtual experiments were performed on lattice images of (110) monocrystalline silicon, and the accuracy of the proposed method was verified. Subsequently, this method was successfully employed to measure the local strain of a mull-layer semiconductor heterostructure. The results were analyzed and compared with those obtained through micro-Raman spectroscopy, showing that the DRM method based on lattice images was generally applicable to analyze the detailed information of the three in-plane strain components with a spatial resolution in the ten-nanometer scale.