本論文主要研究以X光三光布拉格表面繞射(X-ray three-beam Bragg-surface diffraction, BSD)幾何所產生之表面繞射光，將其繞射光引入Y字型波導管中來探究繞射光的強度變化。Y字型波導管使用之基底材料為矽晶圓，以高吸收係數金屬材料鉭(Ta)為其邊界，波導管在中段以後一分為二，改變波導管的分岔角度(0.1º、0.2º、0.3º、0.4º、0.5º)及線寬(25.6 μm、1.6 μm)。最後由掃描式電子顯微鏡(Scanning Electron Microscope, SEM)來觀測樣品的微結構。
實驗利用同步輻射光源來進行；選擇能量為8.8785 keV的X光作為入射光，以矽(002)原子面為對稱的布拉格反射面及(1-31)原子面為不對稱的表面繞射面，以產生由(1-31)原子面產生的表面繞射光並將此表面繞射光引入設計的波導管[110]方向上。
由實驗結果得知當分岔的兩個波導管之夾角小於Ta金屬與Si晶體邊界全反射之臨界角的兩倍時，則可以觀察到繞射光的分光效果；如此之外，當改變波導管方位角時，則會觀察到繞射光在不同方位上的強度大小有所變化。因此，本研究設計的Y字型波導管所造成的分光效果，可應用在X光學上的光流量開關(Flux-Switching)及光流量控制(Flux-Controlling)。

We report that Y-shaped X-ray waveguides can be designed by utilizing the three-beam Bragg-surface diffraction geometry to generate a surface diffracted beam propagating along the direction of the waveguides. Y-shaped waveguides are prepared on a silicon wafer, choosing tantalum with the high absorbing boundary material. The forked angles of waveguides are 0.1, 0.2, 0.3, 0.4 and 0.5 degrees, respectively. The widths of waveguide are 25.6 and 1.6 micrometers. The structure of a Y-shape waveguide is examined by using the Scanning Electron Microscope (SEM).
Diffraction experiments from this designed waveguide are carried out at the National Synchrotron Radiation Center (NSRRC). The Si (002)/(1-31) three-beam Bragg-surface diffraction is employed to generate the surface (1-31) diffracted beam propagating along the [110] preselected direction of the designed waveguide, where (002) is a symmetric Bragg reflection and (1-31) an asymmetric surface diffraction for the photon energy of 8.8785keV.
It is found that beam splitting occurs in this Y-shaped waveguide when the forked angle between the two branches of the waveguide is smaller than two times of the critical angle of the external total reflection of Ta/Si. Also changing the azimuth angle around the [001] can lead to the adjustment of the diffracted beam intensity. We believe that the Y-shaped waveguide can be applied to the flux-switching and the flux-controlling for X-ray optics.

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