Scanning transmission helium ion microscopy on carbon nanomembranes

Beilstein Journal of Nanotechnology

article

Daniel Emmrich¹  Annalena Wolff²  Nikolaus Meyerbröker³  Jörg K. N. Lindner⁴  André Beyer¹  Armin Gölzhäuser¹ 

[1] Physics of Supramolecular Systems and Surfaces, Bielefeld University;Central Analytical Research Facility, Institute for Future Environments, Queensland University of Technology;CNM Technologies;Department of Physics, Paderborn University

关键词: carbon nanomembranes;    dark field;    helium ion microscopy (HIM);    scanning transmission ion microscopy (STIM);    SRIM simulations;   

DOI  :  10.3762/bjnano.12.18

学科分类：环境监测和分析

来源: Beilstein - Institut zur Foerderung der Chemischen Wissenschaften

【 摘 要 】

A dark-field scanning transmission ion microscopy detector was designed for the helium ion microscope. The detection principle isbased on a secondary electron conversion holder with an exchangeable aperture strip allowing its acceptance angle to be tuned from3 to 98 mrad. The contrast mechanism and performance were investigated using freestanding nanometer-thin carbon membranes.The results demonstrate that the detector can be optimized either for most efficient signal collection or for maximum imagecontrast. The designed setup allows for the imaging of thin low-density materials that otherwise provide little signal or contrast andfor a clear end-point detection in the fabrication of nanopores. In addition, the detector is able to determine the thickness of membranes with sub-nanometer precision by quantitatively evaluating the image signal and comparing the results with Monte Carlosimulations. The thickness determined by the dark-field transmission detector is compared to X-ray photoelectron spectroscopy andenergy-filtered transmission electron microscopy measurements.

【 授权许可】

CC BY