목차
1. 서론 1
2. 본론 2
2.1. 동역학적 회절 현상과 세차빔 전자회절의 원리 3
2.2. PED를 활용한 나노 결정의 구조분석의 사례 5
3. 결론 6
참고문헌 7
Fig. 1. The phenomenon of dynamical diffraction in electron scattering once. Any beam which is oriented so as to be Bragg scattered once is automatically in the ideal orientation to be rediffracted. This gives rise to the phenomenon of dynamical scattering because the beam can be diffracted again and again. 3
Fig. 2. The simulated ED patterns of Si [011] as variation of sample thickness. 4
Fig. 3. The simulated HREM images of Si [011] as variation of sample thickness. The overlaid points with blue color indicate Si atoms in the [011] projection. 4
Fig. 4. Schematic diagram of precession electron diffraction. The electron beam precessed by the scan-coil forms the ring-shaped diffraction pattern in the back-focal plane. This ring-shaped pattern should be compensatedto a stationary focused diffraction pattern by the descan alignment. 4
Fig. 5. TEM image of Si crystal for thickness evaluation and three different electron diffraction patterns for six different thickness areas of Si crystal. 5
Fig. 6. Four comparison of SAED and PED patterns of CaMoO₄ [110]: (a) SAED pattern, (b) unfiltered PED pattern, (c) ZL-PED pattern, and (d) PL-PED pattern. 5
Fig. 7. Two examples ofr comparison of XRD and ED intensity data of nano-crystalline materials. (a) Intensity comparision of Lab. source XRD and ED data for 10㎚ MnFe₂O₄ nano-crystals. (b) Intensisty comparison of synchrotron XRD and ED data for 5 nm ZrO₂ nanocrystals. 6
Fig. 8. Bright-field TEM image of the HA nano-powder and four ED patterns of the HA nano-powder. 6
Fig. 9. Schematic diagrams of (a) general electron powder diffraction pattern and (b) precessed electron powder diffraction pattern. 6