Study on Short-Wavelength Soft X-Ray Phase Contrast Microscope

1) x射线相衬显微镜的研制研制了第一台带有相板的泽尼克x射线相衬显微镜。利用高能物理研究所光子工厂的弯曲磁体束线BL3C2同步辐射。9keV的单色x射线入射到样品上。利用沃尔特反射镜对透射图像进行放大，放大倍率为10。由于利用了反射镜环形孔径的一小部分，显微镜只能成像一维方向，且反射镜的形差对子午方向影响严重。在Wolter镜的后焦平面上设置了厚度为5mum的铝箔相板。直径为5-10mum的聚对苯二甲酸乙酯（乙烯）导线在9keV下清晰聚焦，而在亮场情况下无法观察到这一点。2)暗场软x射线显微镜的研制研制了第一台带有Wolter镜的暗场软x射线显微镜。从激光产生的等离子体源发出的软x射线用聚光镜聚焦，聚光镜的环形孔径略小。样品散射的软x射线被聚焦在CCD相机上。可以观察到PMMA图案和生物标本的边缘增强暗场图像。用数控车床和金刚石单点刀具加工无氧铜镜芯。表面粗糙度约为Rq (rms) 9nm。然后，制作了耐热玻璃复制品。反射镜的表面粗糙度约为Rq (rms) 20-30nm，该工艺可以缩短反射镜的制造周期，但对于软x射线和x射线来说，表面粗糙度不够小，并且需要对芯棒和复制的玻璃复制品进行抛光。

1) Development of a phase contrast x-ray microscopeWe developed the first Zernike phase-contrast x-ray microscope with a phase plate. Synchrotron radiation from the bending magnet beamline BL3C2 at the Photon Factory, Institute for High Energy Physics was used. Monochromatic x-rays at 9keV were incident on a specimen. Using a Wolter mirror, the transmission image was enlarged with the magnification ratio of 10. The microscope could image only one-dimensional direction, because the small part of the annular aperture of the mirror was used, and the figure error of the mirror was severely affected to the meridional direction. A phase plate of an aluminum foil of a 5mum thickness was set at the back focal plane of the Wolter mirror. A phase-contrast image of poly(ethylene telephthalate) wires of a 5-10mum diameter was clearly focused at 9keV, that could not be observed in the case of bright field.2) Development of a dark-field soft x-ray microscopeWe developed the first dark-field soft x-ray microscope with Wolter mirrors. Soft x-rays from a laser-produced plasma source were focused with a condenser mirror with the slightly small annular aperture of an objective mirror. Scattering soft x-rays from a specimen were focused on a CCD camera. Edge-enhanced dark-field images of a PMMA pattern and biological specimens could be observed.3) Fabrication of a Wolter mirrorMirror mandrels of oxygen-free copper were turned with a NC lathe and a diamond single-point tool. The surface roughness was about Rq (rms) 9nm. Then, the Pyrex glass replicas were fabricated. The surface roughness of the mirrors was about Rq (rms) 20-30nm, This process of a Wolter mirror fabrication would shorten a fabrication term of a Wolter mirror however the surface roughness was not small enough for soft x-rays and x-rays, and it was necessary to polish a mandrel and a replicated glass replica.