Plan-view transmission electron microscopy specimen preparation for atomic layer materials using a focused ion beam approach
Autor: | Cheng-Yen Wen, Pei-Chin Lee, Chia-Hao Yu, Jih-Shang Huang, Lan-Hsuan Lee, Chuan-Yu Wei |
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Rok vydání: | 2019 |
Předmět: |
010302 applied physics
Auger electron spectroscopy Materials science Graphene Scanning electron microscope 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Focused ion beam Isotropic etching Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials law.invention chemistry.chemical_compound chemistry Electron diffraction law Transmission electron microscopy 0103 physical sciences Composite material 0210 nano-technology Instrumentation Molybdenum disulfide |
Zdroj: | Ultramicroscopy. 197:95-99 |
ISSN: | 0304-3991 |
DOI: | 10.1016/j.ultramic.2018.12.001 |
Popis: | Using the focused ion beam (FIB) to prepare plan-view transmission electron microscopy (TEM) specimens is beneficial for obtaining structural information of two-dimensional atomic layer materials, such as graphene and molybdenum disulfide (MoS2) nanosheets supported on substrates. The scanning electron microscopy (SEM) image in a dual-beam FIB-SEM can accurately locate an area of interest for specimen preparation. Besides, FIB specimen preparation avoids damages and hydrocarbon contamination that are usually produced in other preparation methods, in which chemical etching and polymer adhesion layers are used. In order to reduce harmful ion-beam bombardment and re-deposition on the thin atomic layers during FIB specimen preparation, we develop a method to protect the atomic layers by making a “microcapsule” to insulate the sample surface. The method is applied respectively to prepare plan-view TEM specimens of a graphene sheet with multiple adlayers and MoS2 atomic layers. Useful electron diffraction results can be obtained from these specimens for understanding the interlayer orientation relationships in the two materials. Auger electron spectroscopy analysis further confirms that the sample surface is free from contamination under the sufficient protection given by the proposed method. |
Databáze: | OpenAIRE |
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