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In this paper, we describe a method based on the proposed vertical scanning interferometry (VSI) for the measurement of both surface profile of the micro-cantilever and corresponding etching sacrificial layer beneath the cantilever by only one scanning. A white light source illuminates a micro-cantilever at a certain incident angle through a Mirau interference objective. With this arrangement the top surface of the cantilever and a normally obstructed surface profile beneath the cantilever can be assessed in the same system. A digital filtering technique based on Fourier transform and a Gaussian fit are implemented to simultaneously retrieve an envelope of two series of interferograms at the top surface of a cantilever and as well as area of interest underneath the cantilever. The retrieved envelope peaks, which represent the height information of points on the test surface, are plotted to show whole field surface contour and demonstrate its effectiveness as a means for micro-electro-mechanical systems (MEMS) dual/multi-layer inspection. Results obtained agree well with those of a commercial instrument and show that the proposed method is simple and accurate. 相似文献
975.
附认股权公司债是公司债附有认股权证的新型金融产品.本介绍了附认股权公司债的定义;给出了附认股权公司债的定价模型,并给出了仿真案例. 相似文献
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Y. Yang B.K. Tay X.W. Sun H.M. Fan Z.X. Shen 《Physica E: Low-dimensional Systems and Nanostructures》2006,31(2):218-223
Amorphous silica [SiOx (1<x<2)] nanowires were fabricated on silicon substrate in an acidic environment by heating the mixture of ZnCl2, and VO2 powders at 1100 °C. The length of SiOx nanowires ranges from micrometers to centimeters, with uniform diameters of 10–500 nm depending on substrate temperature. Room-temperature photoluminescence spectra of the SiOx nanowires showed two strong luminescence peaks in the red and green region, respectively. The photoluminescence was suggested to originate from nonbridging oxygen hole center (red band), and hydrogen-related species in the structure of SiOx (green band). The study on chemical reactions and growth of the SiOx nanowires revealed the formation process of silica nanowires in acidic environment was closely related to the vapor–solid–liquid mechanism. 相似文献
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979.
Fei Guan Miao Chen Wu Yang Jinqing Wang Shengrong Yong Qunji Xue 《Applied Surface Science》2005,240(1-4):24-27
Patterned gold microstructures on glass or Si wafers have been fabricated by a novel method which is composed of selective electroless plating and microcontact printing. This process may be widely used for the production of fine metal patterns in printed circuits or as a substrate to form patterned SAMs. In addition, these patterned metal microstructures can be readily transferred to adhesive tape surface to fabricate flexible metal microstructure, which may be applied in all-plastic circuit. 相似文献
980.
Weitian Wang Zhenhong Dai Yuming Sun Yuanping Sun Dongyi Guan 《Applied Surface Science》2005,250(1-4):268-272
Well-crystallized Ba0.5Sr0.5TiO3 thin films with good surface morphology were prepared on MgO(1 0 0) substrates by pulsed laser deposition technique at a deposition temperature of 800 °C under the oxygen pressure of 2 × 10−3 Pa. X-ray diffraction and atomic force microscopy were used to characterize the films. The full width at half maximum of the (0 0 2) Ba0.5Sr0.5TiO3 rocking curve and the root-mean-square surface roughness within the 5 μm × 5 μm area were 0.542° and 0.555 nm, respectively. The nonlinear optical properties of the films were determined by a single beam Z-scan method at a wavelength of 532 nm with laser duration of 55 ps. The results show that Ba0.5Sr0.5TiO3 thin films exhibit a fast third-order nonlinear optical response with the nonlinear refractive index and nonlinear absorption coefficient being n2 = 5.04 × 10−6 cm2/kW and β = 3.59 × 10−6 (m/W), respectively. 相似文献