کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1588674 1515127 2016 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Impact of dynamical scattering on quantitative contrast for aberration-corrected transmission electron microscope images
ترجمه فارسی عنوان
اثر پراکندگی دینامیکی بر روی کنتراست کمی برای تصاویر میکروسکوپ الکترونی عبور تصحیح شده با تغییرات تصحیح شده
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد دانش مواد (عمومی)
چکیده انگلیسی
Aberration-corrected transmission electron microscope images taken under optimum-defocus conditions or processed offline can correctly reflect the projected crystal structure with atomic resolution. However, dynamical scattering, which will seriously influence image contrast, is still unavoidable. Here, the multislice image simulation approach was used to quantify the impact of dynamical scattering on the contrast of aberration-corrected images for a 3C-SiC specimen with changes in atomic occupancy and thickness. Optimum-defocus images with different spherical aberration (CS) coefficients, and structure images restored by deconvolution processing, were studied. The results show that atomic-column positions and the atomic occupancy for SiC 'dumbbells' can be determined by analysis of image contrast profiles only below a certain thickness limit. This limit is larger for optimum-defocus and restored structure images with negative CS coefficient than those with positive CS coefficient. The image contrast of C (or Si) atomic columns with specific atomic occupancy changes differently with increasing crystal thickness. Furthermore, contrast peaks for C atomic columns overlapping with neighboring peaks of Si atomic columns with varied Si atomic occupancy, which is enhanced with increasing crystal thickness, can be neglected in restored structure images, but the effect is substantial in optimum-defocus images.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Micron - Volume 89, October 2016, Pages 77-86
نویسندگان
, ,