Diffraction Pattern and Dynamical Analysis of Wide-Angle Incident X-ray Surface Diffraction from Silicon Nano-Wire

• Main Authors: Chen, Hsin-Yi, 陳心誼
• Other Authors: Chang, Shih-Lin
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/00578038992132928618

博士 === 國立清華大學 === 物理系 === 100 === This work aims to study the diffraction pattern and dynamical analysis of asymmetric surface diffraction from a nano-structure on a chip. This studying is able to design a wide-angle incidence x-ray optical device using crystal surface diffraction. We have investigated the possibility of the opical device. Nano-structures were prepared on a 6-in Si (001) wafer. The Si (113) is chosen as an asymmetric surface diffraction for the photon energy 8.8785 keV according to the Si crystal orientation and diffraction geometry. The experimental results may be summarized as follows. First, there are two diffraction peaks in vertical direction for bare silicon, which are diffracted beam Si (113) and specular reflection of Si (113). The experimental results are in good agreement with the theoretical calculations using the dynamical theory of x-ray diffraction. Second, four peaks were measured in vertical direction for silicon nano-wire. Two of peaks were from bare silicon due to width of silicon nano-wire is much smaller than incident beam spot in horizontal direction. The other two peaks due to a silicon nano-wire and its specular reflection. The ray tracing of a silicon nano-wire was drawn. Finally, the schematic design of wide-angle incidence x-ray waveguide is Au/Si/Au sandwich system with Si as the guiding layer and Au as cladding layer. The surface diffracted beam can be confined and propgated inside the silicon nano-wire if the total refection occurs. In additional, I have introduced an algorithm, Diffraction Pattern Algorithm, to get the diffraction patter. The correlation between excitation of mode inside the crystal and diffraction pattern outside the crystal can be illustrated by experimental data and theoretical calculation using the algorithm. Keyword: asymmetric surface diffracted beam, the dynamical theory of x-ray diffraction, wide-angle incidence x-ray waveguide