• Applied Microscopy
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• 제46권2호
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• pp.110-115
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• 2016

Transmission electron microscopy (TEM) is a powerful tool for analyzing a broad range of materials and provides localized information about the microstructure. However, the analysis results are strongly influenced by the quality of the thin foil specimen. Sample preparation for TEM analysis requires considerable skill, especially when the area of interest is small or the material of interest is difficult to thin because of its high hardness and its mechanical instability when thinned. This article selectively reviews recent advances in TEM sample preparation techniques using a tripod polisher. In particular, it introduces two typical types (fl at type and wedge type) of TEM sample preparation and the benefits and drawbacks of each method; finally, a method of making better samples for TEM analysis is suggested.

• 한국재료학회지
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• 제13권9호
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• pp.598-605
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• 2003

The optimized conditions for the cross-sectional TEM sample preparation using tripod polisher and ion-beam miller was confirmed by AFM and TEM. For the TEM observation of interfaces including InGaN layers like InGaN/GaN MQW structures, the sample preparation by the only tripod polishing was useful due to the reduction of artifacts. On the other hand, in case of the thick nitride films like ELO, PE, and superlattice, both tripod polishing and controlled ion-beam milling were required to improve the reproducibility. As a result, the ion-beam milling with the $60^{\circ}$modulation showed the minimum height difference between film and sapphire interface and the ion-beam milling of the $80^{\circ}$modulation showed the broad observable width.

• Applied Microscopy
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• 제34권2호
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• pp.95-102
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• 2004

본 실험에서는 tripod polishing 방법을 이용하여 Pd/GaN/Sapphire 박막, PZT/MgO/Si 박막, 304 stainless steel 분말, $Mo_5Si_3/Mo_2B$ diffusion couple의 매우 다양한 물성이 포함된 불균질 재료의 TEM 시편을 제작하고 분석하였다. Tripod polishing을 사용하여 시편을 준비하면 시편의 종류에 관계없이 시편의 선단부에 매우 광범위한 전자빔 투과 영역을 지닌 TEM 시편을 얻을 수 있었으며, Pd/GaN/Sapphire 박막, PZT/MgO/Si 박막과 같이 기판이 경한 반도체 재료의 경우에는 연마 정도가 균일하며 연마과정 동안 오염이 심하지 않기 때문에 ion milling으로 cleaning 없이 TEM 관찰이 가능하다. 한편 304 stainless steel 분말과 같은 금속재료의 경우 짧은 시간의 ion milling 은 시편의 오염 제거에 도움된다. $Mo_5Si_3/Mo_2B$ diffusion couple에 형성된 실리사이드는 큰 취성 때문에 polishing 동안 시편이 깨지는 현상으로 전자가 투과할 수 있을 정도의 연마가 불가능하여 1시간 정도 ion milling 연마가 필요하다. Tripod polishing으로 TEM 시편을 준비하면 분석하고자 하는 지역을 정확하고도 넓게 연마할 수 있다. 또한 비교적 짧은 시간 내에 ion milling 없이 TEM 시편을 제작할 수 있기 때문에 ion milling에서 유발되는 여러 가지 문제점들을 해결할 수 있는 장점이 있었다. 그러나 tripod polishing은 전부 수작업으로 시편을 준비하기 때문에 시편을 제작하는 과정 동안 매우 세심한 주의가 요구되며 제작자의 숙련도와 경험을 필요로 하는 단점이 있다.

• 한국초전도ㆍ저온공학회논문지
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• 제8권1호
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• pp.9-14
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• 2006

Sample preparation plays a critical role in microstructure analysis using TEM. Although TEM specimen has been usually prepared by jet-polishing or Ar-ion beam milling technique. these methods could not be applied to YBCO CC which is composed of IBAD or RABiTS substrates, several buffet layers, and YBCO superconducting layer because of big difference in mechanical strengths between the metallic phase and oxide phases. To obtain useful cross-sectional information such as interface between the phases or second phases in YBCO CC, it is prerequisite to secure the large area of thin section in the cross-sectional direction. The superconducting layer or the buffer layers are relatively weak and fragile compared to the metallic substrate such as Ni-5wt%W RABiTS of Hastelloy-based IBAD, and preferential removal of weak ceramic phases during polishing steps makes specimen preparation almost impossible. Tripod polisher and small jig were home-made and employed to sample preparation. The polishing angle was maintained <$1^{\circ}$ throughout the polishing steps using 2 micrometers attached to the tripod plate. TEM specimens with large and thin area could be secured and used for RABiTS/IBAD substrate analyses. In some cases, additional Ar-beam ion milling with low beam current and impinging angle was used for less than 30 sec. to remove debris or polishing media attacked to the specimens.