The Design and Fabrication of X-Ray Reflective and Diffractive Interference Optical Device and Their Application in X-Ray Microscopy

• Main Authors: Che-I Devin Su, 蘇哲毅
• Other Authors: Yeukuang Hwu
• Format: Others
• Language: en_US
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/40505565862283961105

碩士 === 國立臺灣海洋大學 === 光電科學研究所 === 94 === Base on the interference optics and with the integrated x-ray microscopy and the state-of-the-art nanofabrication techniques, we present the results of a synchrotron radiation study of the relevant technology of focusing x-rays; one is the Lloyd’s mirror, a reflective optics based wavefront splitting interferometer; and another is the Fresnel zone plate, a focusing device based on both phase shift theory and diffractive optics. In this thesis, we demonstrate a practical and simple approach to implement the Lloyd’s mirror system and characterized their performance in focusing hard-x-rays and the possibility of using this system as tool for materials characterization. We found that the peak intensity of the interference fringes were significantly increased from its respective incident beam after passing through a Lloyd’s mirror independent from the monochromaticity of the hard x-rays or monochromatic x-rays. This make these devices particularly suitable for focusing of nonmonochrmatic x-rays. Second, with an simple high resolution x-ray microscope, the Lloyd’s mirror provides a simple inspection method of the characteristics of the x-ray beam, such as the source size, the divergence and therefore the coherence of the source which is otherwise difficult to measure. The Lloyd’s mirror used with hard x-rays is very sensitive to the surface quality which leads to the possibility to use it to examine the surface quality. With the advance nanofabrication, we also successfully provide extremely high quality Frensnel zone plate for multi-keV hard x-rays capable of focusing or imaging x-rays down to 30nm. During the fabrication process, we found that both the nitride membrane, which provided the whole structure a free standing interface, and the metal membrane, which provided the electroplating a conductive layer in our fabrication processes, their quality and thickness directly influences the focusing efficiency of end products. In addition, the design and the thickness of Fresnel zone plate structure play a very important role to the focusing efficiency of this device.