• 제목/요약/키워드: electron microscopy.

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Three-Dimensional Automated Crystal Orientation and Phase Mapping Analysis of Epitaxially Grown Thin Film Interfaces by Using Transmission Electron Microscopy

  • Kim, Chang-Yeon;Lee, Ji-Hyun;Yoo, Seung Jo;Lee, Seok-Hoon;Kim, Jin-Gyu
    • Applied Microscopy
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    • 제45권3호
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    • pp.183-188
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    • 2015
  • Due to the miniaturization of semiconductor devices, their crystal structure on the nanoscale must be analyzed. However, scanning electron microscope-electron backscatter diffraction (EBSD) has a limitation of resolution in nanoscale and high-resolution electron microscopy (HREM) can be used to analyze restrictive local structural information. In this study, three-dimensional (3D) automated crystal orientation and phase mapping using transmission electron microscopy (TEM) (3D TEM-EBSD) was used to identify the crystal structure relationship between an epitaxially grown CdS interfacial layer and a $Cu(In_xGa_{x-1})Se_2$ (CIGS) solar cell layer. The 3D TEM-EBSD technique clearly defined the crystal orientation and phase of the epitaxially grown layers, making it useful for establishing the growth mechanism of functional nano-materials.

Transmission Electron Microscopy Sample Preparation of Ge2Sb2Te5 Nanowire Using Electron Beam

  • Lee, Hee-Sun;Lee, Jun-Young;Yeo, Jong-Souk
    • Applied Microscopy
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    • 제45권4호
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    • pp.199-202
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    • 2015
  • A simple and novel transmission electron microscopy (TEM) sample preparation method for phase change nanowire is investigated. A $Ge_2Sb_2Te_5$ (GST) nanowire TEM sample was meticulously prepared using nanomanipulator and gas injection system in a field emission scanning electron microscopy for efficient and accurate TEM analysis. The process can minimize the damage during the TEM sample preparation of the nanowires, thus enabling the crystallographic analysis of as-grown GST nanowires without unexpected phase transition caused by e-beam heating.

그리드 컴퓨터를 이용한 초고전압 투과전자현미경 원격제어 시스템 (High Voltage Electron Microscopy Remote Access System Using Grid Computer)

  • 안영헌;허만회;권희석;김윤중
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (A)
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    • pp.580-582
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    • 2005
  • 거리가 상당히 먼 곳에서 고가의 장비를 사용하기 위해서는 사용할 연구 인력이 직접 와야 하는 많은 시간적 비용적 문제가 발생한다. 특히 본원에 장비되어 있는 초고전압 투과전자현미경(High Voltage Electron Microscopy - 이하 HVEM)의 경우 고가의 장비로 지역마다 기기를 구비할 수 없어 사용자는 직접 장비가 있는 연구실까지 와서 사용해야 한다. HVEM은 1천만 배율의 성능을 가진 국내 유일은 물론 전 세계적으로도 손꼽히는 고성능의 투과전자현미경으로 NT(Nano Technology), BT(Bio Technology) 연구에 있어서 핵심적인 역할을 하는 청단 연구기기이다. 따라서 본 논문에서는 그리드 컴퓨터 기술을 이용하여 HVEM을 원격제어 하는 시스템을 구축하였다.

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전자현미경을 이용한 나노셀룰로오스 물질의 형태학적 특성 분석 연구 (Electron Microscopy for the Morphological Characterization of Nanocellulose Materials)

  • 권오경;신수정
    • 펄프종이기술
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    • 제48권1호
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    • pp.5-18
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    • 2016
  • Electron microscopy is an important investigation and analytical method for the morphological characterization of various cellulosic materials, such as micro-crystalline cellulose (MCC), microfibrillated cellulose (MFC), nanofibrillated cellulose (NFC), and cellulose nanocrystals (CNC). However, more accurate morphological analysis requires high-quality micrographs acquired from the proper use of an electron microscope and associated sample preparation methods. Understanding the interaction of electron and matter as well as the importance of sample preparation methods, including drying and staining methods, enables the production of high quality images with adequate information on the nanocellulosic materials. This paper provides a brief overview of the micro and nano structural analysis of cellulose, as investigated using transmission and scanning electron microscopy.

이미지 전처리를 이용한 전자현미경 볼륨 랜더링 시스템 (Volume Rendering System of Electron Microscopy using Image preprocessiong)

  • 정원구;정종만;이지영;이호;최상수;권희석;김윤중
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2008년도 추계학술발표대회
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    • pp.100-103
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    • 2008
  • 한국기초과학지원연구원(KBSI, Korea Basic Science Institute)에서는 국내 유일의 초고전압투과전자현미경(HVEM, High Voltage Electron Microscopy)을 비롯하여 3대의 일반투과 전자현미경을 보유하고 있다. 전자현미경을 통하여 관찰된 이미지는 각 단계별로 tilting 되어 저장된 이미지로서 관찰자에게 보다 나은 관찰 환경의 구성을 위해 3D로의 reconstruction은 필수 과정이라고 할 수 있겠다. 이 과정 중 카메라 중심에서 벋어난 부분의 왜곡을 워핑기법을 통하여 최대한 감소시킨다. 이런 전처리 과정을 통하여 3D 구조물을 구성하게 되면 초기 이미지를 그대로 사용하는 것보다 한 단계 더 나은 결과물을 얻어낼 수 있다. 이미지 전처리를 이용한 전자현미경 볼륨 랜더링 시스템의 구축은 관찰자에게 보다 편리하며 빠른 실험 환경을 제공하여 줄 수 있고, 이해하기 쉽고 실제 모습에 가까운 형태의 실험 결과물을 접할 수 있게 된다.

Noise2Atom: unsupervised denoising for scanning transmission electron microscopy images

  • Feng Wang;Trond R. Henninen;Debora Keller;Rolf Erni
    • Applied Microscopy
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    • 제50권
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    • pp.23.1-23.9
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    • 2020
  • We propose an effective deep learning model to denoise scanning transmission electron microscopy (STEM) image series, named Noise2Atom, to map images from a source domain 𝓢 to a target domain 𝓒, where 𝓢 is for our noisy experimental dataset, and 𝓒 is for the desired clear atomic images. Noise2Atom uses two external networks to apply additional constraints from the domain knowledge. This model requires no signal prior, no noise model estimation, and no paired training images. The only assumption is that the inputs are acquired with identical experimental configurations. To evaluate the restoration performance of our model, as it is impossible to obtain ground truth for our experimental dataset, we propose consecutive structural similarity (CSS) for image quality assessment, based on the fact that the structures remain much the same as the previous frame(s) within small scan intervals. We demonstrate the superiority of our model by providing evaluation in terms of CSS and visual quality on different experimental datasets.

Cross-Sectional Transmission Electron Microscopy Specimen Preparation Technique by Backside Ar Ion Milling

  • Yoo, Jung Ho;Yang, Jun-Mo
    • Applied Microscopy
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    • 제45권4호
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    • pp.189-194
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    • 2015
  • Backside Ar ion milling technique for the preparation of cross-sectional transmission electron microscopy (TEM) specimens, and backside-ion milling combined with focused ion beam (FIB) operation for electron holography were introduced in this paper. The backside Ar ion milling technique offers advantages in preparing cross-sectional specimens having thin, smooth and uniform surfaces with low surface damages. The back-side ion milling combined with the FIB technique could be used to observe the two-dimensional p-n junction profiles in semiconductors with the sample quality sufficient for an electron holography study. These techniques have useful applications for accurate TEM analysis of the microstructure of materials or electronic devices such as arrayed hole patterns, three-dimensional integrated circuits, and also relatively thick layers (> $1{\mu}m$).

Precise Comparison of Two-dimensional Dopant Profiles Measured by Low-voltage Scanning Electron Microscopy and Electron Holography Techniques

  • Hyun, Moon-Seop;Yoo, Jung-Ho;Kwak, Noh-Yeal;Kim, Won;Rhee, Choong-Kyun;Yang, Jun-Mo
    • Applied Microscopy
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    • 제42권3호
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    • pp.158-163
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    • 2012
  • Detailed comparison of low-voltage scanning electron microscopy and electron holography techniques for two-dimensional (2D) dopant profiling was carried out with using the same multilayered p-n junction specimen. The dopant profiles obtained from two methods are in good agreement with each other. It demonstrates that reliability of dopant profile measurement can be increased through precise comparison of 2D profiles obtained from various microscopic techniques.

Cellulosome-Like Structures in Ruminal Cellulolytic Bacterium Ruminococcus albus F-40 as Revealed by Electron Microscopy

  • Kim, Y.S.;Singh, A.P.;Wi, S.G.;Myung, K.H.;Karita, S.;Ohmiya, K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권10호
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    • pp.1429-1433
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    • 2001
  • This study provides electron microscopic evidence for the presence of cellulosome-like structures on the cell surface of Ruminococcus albus F-40. Electron microscopy showed that clusters of tightly packed spherical particles were located on the cell surface of R. albus. The protuberant structures present mainly on the bacterial surface and also bound to the cellulose substrate appeared to be the site of cellulosome-like structures. From the evidence presented, we suggest that the structures described here might be a characteristic feature of some ruminal cellulolytic bacteria.