Applied Microscopy

Korean Society of Microscopy (한국현미경학회)
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Experiment of Usefulness of IWFR Analysis for High Voltage HRTEM Images with a Series of Defocus Steps Obtained from a Relatively Thick Crystal

비교적 두꺼운 결정으로부터 얻은 일련의 비 초점 단계의 고전압 HRTEM 영상들에 대한 IWFR 분석의 유용성 실험

  • Oh, Sang-Ho (Division of Electron Microscopic Research, Korea Science Institute) ;
  • Kim, Youn-Joong (Division of Electron Microscopic Research, Korea Science Institute) ;
  • Kim, Hwang-Su (Department of Physics, Kyungsung University)
  • 오상호 (한국기초과학지원연구원 전자현미경연구부) ;
  • 김윤중 (한국기초과학지원연구원 전자현미경연구부) ;
  • 김황수 (경성대학교 이과대학 물리학과)
  • Published : 2008.12.31
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Abstract

In this paper we have examined the usefulness of IWFR (the iterative wave-function reconstruction) analysis for through-focal series of high-resolution images for a relative thick crystal. In the work we employed JEOL ARM 1300S, and observed the high-resolution images for a Si crystal at the two orientations of [01-1] and [11-2] having 30 nm and 35 nm thickness respectively. As a result of applying IWFR method on the images we found out that even for a thick crystal by the method we can retrieve the exit-surface wave function. However because of the strong dynamical scattering effect, the image pattern of the function reflects only qualitatively the atomic column structure of the crystal examined. Nevertheless it is no doubt that the pattern would give important clue for the crystal structure.

이 논문에서는 비교적 두꺼운 결정에 대한 일련의 고 분해 영상들에 대한 IWFR 분석의 유용성을 실험하였다. 이를 위해 JEOL ARM 1300S를 이용하여 실리콘 결정의 30 nm 두께의 [01-1] 방위와 35 nm 두께의 [11-2]에 대한 일련의 비 초점 단계의 고 분해 영상들을 관찰하였다. 이로부터 두꺼운 시료에 대해서도 IWFR 분석 결과로부터 결정 밑 표면의 파동함수를 얻을 수 있음이 밝혀졌다. 그러나 강한 동역학적 산란에 의한 효과 때문에, 이 함수의 영상패턴은 시료의 원자열 구조의 패턴을 다만 정성적으로만 반영하고 있다. 그럼에도 불구하고 이 패턴은 결정구조의 중요한 단서를 제공할 것임은 의심의 여지가 없다

Keywords

References

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