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ABSTRACT: The soft X-ray interferometry is completed by the Mach-Zehnder interferometer using a soft X-ray laser, and it is also an
important method to measure the electron densities of a laser-produced plasma near the critical surface. It is apparently
demonstrated in this paper that the incident angle of each optical element in the soft X-ray Mach-Zehnder interferometer should
be near normal incidence based on the polarized characteristics of the soft X-ray multilayers, and the product of reflectivity
and transmission of the beam splitter should be taken as a standard of design according to the structure of the soft X-ray
Mach-Zehnder interferometer. The beam splitters used in the soft X-ray interferometry at 13.9 nm are fabricated using the
ion beam sputtering. The figure error of the beam splitter has reached the nanometer magnitude, in which the product of reflectivity
and transmission of the beam splitter is more than 1.6%.
Keywordssoft X-ray-beam splitter-multilayer-interference
Chinese Science Bulletin 04/2012; 48(18):1930-1933. · 1.32 Impact Factor
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ABSTRACT: We describe a simple and convenient method of controlling the profile of a blazed grating that consists of using a patterned native-oxide layer of off-cut silicon (111) wafers as the mask of anisotropic etching to maximize the smooth blaze facets of the desired blaze angle and to minimize the deficiencies of the groove apexes. With the blazed-grating profile well controlled by this technique, a 1200 g/mm blazed grating was fabricated that had a blaze angle of 5.0 degrees and smooth blaze facets of about 0.2 nm rms. It was measured to have blaze efficiency in the vacuum-ultraviolet wavelength region.
Optics Letters 05/2009; 34(8):1147-9. · 3.40 Impact Factor
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ABSTRACT: Grating beam splitters have been fabricated for soft X-ray Mach- Zehnder interferometer using holographic interference lithography. The grating beam splitter consists of two gratings, one works at X-ray laser wavelength of 13.9 nm with the spatial frequency of 1000 lines/mm as the operation grating, the other works at visible wavelength of 632.8 nm for pre-aligning the X-ray interferometer with the spatial frequency of 22 lines/mm as the pre-alignment grating. The two gratings lie vertically on the same substrate. The main feature of the beam splitter is the use of low-spatial- frequency beat grating of a holographic double frequency grating as the pre-alignment grating of the X-ray interferometer. The grating line parallelism between the two gratings can be judged by observing the diffraction patterns of the pre-alignment grating directly.
Optics Express 10/2008; 16(19):14761-70. · 3.59 Impact Factor
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ABSTRACT: A method to improve the accuracy of the wavelength encoding varied line-space grating displacement sensor is presented. Based on the detailed analysis of the measured displacement errors from the single-mirror configuration sensor, a dual-reflector configuration is used to replace the previous configuration, and greatly decreases its errors. Experiments are conducted in order to make comparison of the two configurations. The results show that the measured displacement error of the sensor with dual-reflector configuration is lower than 0.03 mm in full scale (0 to 50 mm), only about 10% of the sensor with single-mirror configuration.
Review of Scientific Instruments 05/2008; 79(4):046105. · 1.37 Impact Factor
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ABSTRACT: We demonstrate a method of fabricating varied-line-spacing grating by employing elastic medium with variable vertical section. The advantages of this technique include continuous variation of line spacing, high fabrication efficiency, low cost, etc. It is very difficult or impractical to produce this variation of line spacing by traditional interference lithography. This kind of grating can be used in an optical position sensor to improve the precision of the sensor.
Optics Express 09/2004; 12(17):3894-9. · 3.59 Impact Factor
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ABSTRACT: Soft X-ray Microscopy station is one of the first constructed facilities at NSRL. The main instrument of the beamline is a monochromator which can provide the monochromized X-rays varying from 2.0 nm to 5.0 nm. Our holographic image employs the X-rays, so called “water window,” and experimental setup is arranged in a Gabor in-line way. Holograms are recorded on the photoresist polymethyl methacrylate (PMMA) and readout with ordinary light microscopes or atomic force microscopes (AFMs). They are reconstructed using optical or numerical methods. So far the holograms of some samples and their reconstructed images are acquired. Those samples include minute granules, cobweb and so on. The estimated resolution of the reconstructed images reaches the level of submicron. It is limited by the coherence of the X-rays used for these experiments. And it is possible to improve the resolution in the future. © 2000 American Institute of Physics.
AIP Conference Proceedings. 05/2000; 507(1):493-496.
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ABSTRACT: A novel process that combines interference lithography and ion beam etching is presented for fabrication of magnetic submicron structures and nanostructures in this paper. Instead of an antireflective coating, vertical standing wave patterns were removed using oxygen descumming process. A series of magnetic submicronmeter structures were fabricated on Co 0.9 Fe 0.1 films by this technique. Fabrication of magnetic nanostructures was performed by using a high exposure dose and modifications in optimized development conditions. A thin Au film was deposited on the sidewall of the magnetic nanostructures to avoid the oxidation of Co and Fe. The effect of this method was confirmed by X-ray photoelectron spectroscopy (XPS). Hysteresis loops measured by a highly sensitive superconducting quantum interference device (SQUID) technique show the different magnetic properties of the magnetic patterns with different critical dimensions.
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ABSTRACT: The performance of a optical component is greatly dependent on its surfaces. There are many ways to measure and evaluate a surface so far, but actually no one knows exactly what a "real" surface likes, and thus makes some measurement unexplainable. This paper develops a way to construct various synthetic surfaces. Referred to actual AFM measurement, regular or irregular surfaces can be created and studied. Bumps, scratches, granules, profile errors and other construction elements can be added to form a very complicated virtual surface. The number, size and distribution of these elements can be changed, and if necessary, the surface roughness can be controlled in a specialized range. As these surfaces are created synthetically, we know exactly what construction these surface contain. The height data of created virtual surfaces can be transferred into the file that AFM instrument can read and handle. As a typical example, a very complicated surface is created step by step in this paper, and its PSD for each step are calculated. This process mikes it very clear how the surface component element affect its PSD function, and is benefit to our better understanding of real surface construction.
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ABSTRACT: With holographic-ion beam etching technique, a number of self-supporting transmission gratings (SSTGs) have been fabricated for inertial confmement fusion (ICF) diagnosis. In addition to the general process, a practical method for monitoring the evolution of the grating structures exposed in photoresist during development of the resist. The real-time monitor technique developed here is relatively simple in comparison with a He-Ne laser and detector, which needs delicate control.
