Very thin poly-SiC films for micro/nano devices

We report characterization of nitrogen-doped, very thin, low-stress polycrystalline silicon carbide (poly-SiC) films suitable for fabricating micro/nano devices. The poly-SiC films are deposited on 100 mm-diameter (100) silicon wafers in a large-scale, hot-wall, horizontal LPCVD furnace using SiH2Cl2 and C2H2 as precursors and NH, as doping gas. The deposition temperature and pressure are fixed at 900 degrees C and 4 Torr, respectively. The deposition rate increases substantially in the first 50 minutes, transitioning to a limiting value thereafter. The deposited films exhibit (111)-orientated polycrystalline 3C-SiC texture. HR-TEM indicates a 1 nm to 4 nm amorphous SiC layer at the SiC/silicon interface. The residual stress and the resistivity of the films are found to be thickness dependent in the range of 100 nm to 1 microm. Films with thickness less than 100 nm suffer from voids or pinholes. Films thicker than 100 nm are shown to be suitable for fabricating micro/nano devices.     

Optimal design scheme based on the segmental transmission line methodology for high-frequency interconnection in 3D micro/nano integration

With the continuous growth of signal frequency and package density, discontinuity of the high-frequency inter-connection in 3D micro/nano integration becomes un...     

以CuCl纳米棒薄膜为前驱体制备CuS纳米/微米管和CuO纳米/微米晶薄膜

在本文中,以由氯化亚铜纳米棒组成的薄膜为前驱体,分别通过气-固相的硫化和氧化反应获得了由直径150到200纳米,长度达数微米的硫化铜管组成的薄膜和粒径为150到200纳米的氧化铜纳米/微米晶所组成的薄膜.利用XRD,SEM,TEM测试方法对薄膜的晶化度,纯度,形貌及结构特点进行了分析.制备的薄膜具有大尺寸,高比表面积,构筑单元为单晶的特点.研究表明,硫化铜纳米/微米管是通过克肯达尔效应形成的,而氧化铜纳米/微米晶是氯化亚铜与空气反应通过类似于化学气相沉积过程形成的.     

Micro-prober for wafer-level low-noise measurements in MOS devices

Low-frequency noise measurements represent an interesting investigation technique for the characterization of the quality and reliability of microelectronic materials and devices. Performing meaningful noise measurements at low and very low (f<1 Hz) frequencies, however, may be quite challenging, particularly because of the many sources of interference that superimpose on the noise signal. For this reason, packaged samples are preferred because they allow accurate shielding from the external environment, and because keeping the sample in close proximity to the low-noise biasing system and amplifier reduces microphonic and electromagnetic disturbances. Notwithstanding this, the possibility of performing low-frequency noise measurements at wafer level would be quite interesting, both because of the ease of obtaining wafer-level samples from industries with respect to packaged samples, and because this would avoid possible packaging-process induced device degradation. The purpose of this work is to demonstrate that it is, in fact, possible to design and build a dedicated probe system for performing high-sensitivity, low-frequency noise measurements on metal-oxide-semiconductor devices at wafer level.     

激光直写制备金属与碳材料微纳结构与器件研究进展

激光直写技术作为一种新兴的低成本、高效、高精度的加工技术,可以适用于几乎任意自由度的二维或者三维微纳结构快速成型制备.这对光电子以及半导体微纳结构与器件的制备具有重大的意义.金属微纳结构在电子学和光子学中有着广泛的应用.本文综述了激光直写制备金属微纳结构相关研究进展.主要包括激光直写制备金、银、铜以及复合材料微纳结构与...     

Investigation of method for measuring adhesion force of ice in nano/micro scale by using SPM

Ice adhesion to a cooling solid surface occurs in many situations, and it causes many serious problems that can lead to economic losses. Therefore, it is necessary to clarify the mechanism of ice adhesion to a cooling surface. In past studies, the adhesion force of ice was reported to be strongly governed by the surface energy of the cooling solid surface. In consideration of this surface energy, it is essential to investigate the ice adhesion force on a nano/micro scale. However, very little research has been conducted in nano/micro scale. Thus, in this paper, by using a scanning probe microscope (SPM), the methods for measuring the ice adhesion force and contact area between the cooling solid surface and formed ice are proposed, and the optimal measurement conditions of the SPM are determined. Then, the validity and effectiveness of the method are clarified.     

微米/纳米胶束型自修复涂料的制备

主要讨论了基于微米/纳米胶束的自修复涂料的制备。量化了工艺及其在涂料领域中潜在的应用。     

Foreword to the special issue on micro/nano biosensors

正Micro/nano biosensors had rapidly progressed and enabled a verity of applications that were otherwise impossible/challenging with traditional methods. The three key components in micro/nano biosensors consist of (1) the analyte preparation (living cells or biomarker molecules),(2) signal transduction (from bio-signal/event to more readable electronic/optical signal), and (3) signal readout (preferably by integrated instrumentation). A verity of work has been dedicated to each     

Accurate and consistent FE modelling of soft docking of micro/nano paired-satellites using variational inequalities

Time-dependent variational inequality-based formulations describing the behavior of elastodynamic contact problems have been used to model the soft docking of micro/nano paired-satellites. The solution strategy is based upon the iterative use of two subproblems. In the first subproblem, the technique of Quadratic Programming was used to predict the contact surface and the stresses acting on it. In the second subproblem, the technique of Lagrange multipliers was used to impose the boundary conditions and contact constraint obtained in step I. The solution accounts for the effect of friction through the use of an appropriate regularization technique in the virtual work expressions. The accuracy of the proposed variational inequality (VI) model of the soft docking process is validated by comparing the VI results with commercially available software. Finally, the effects of the bending stiffness of the docking probe, the friction between the candidate contact surfaces are investigated and analyzed using the newly developed model.     

A micro flow cell cytometry based on MEMS technologies using silicon and optical fibers

In this paper, we tested multi-mode optical fibers to select a suitable fiber for effective flow of cell cytometry. In order to align micro nozzle and multi-mode optical fibers, a guide channel was fabricated by silicon wafer etching with MEMS (Micro Electro-Mechanical System) technologies. The fabricated system is advantageous due to its low cost and simplicity in construction. It is possible because multi-mode optical fibers replace many optical lenses and expensive equipment. As a result of the flow cell cytometry using multi-mode optical fibers for both input and output, it is easy to align and we can reduce power consumption. The sensitivity of the micro flow cell cytometry is much better than other cytometries. The output voltage was as high as 300 mV. We injected various cells through the designed and fabricated flow cell cytometry, and we were able to detect cells. Every cell has its own cellulose and wall which cause different light permeability; therefore, we could get different voltage characteristics according to different cells. From the experimental results, we were able to count the number of cells and differentiate the relative size of the injected cells; therefore, we can use the micro flow cell cytometry for analyzing cells [1, 2].     

Multicasting optical interconnects using liquid crystal over silicon devices

This work presents the characteristics and expected capabilities of an optical interconnect that uses a diffractive liquid crystal over silicon (LCOS) device as a routing element. Such an interconnect may be used in a neighborhood's optical network to distribute high definition television, thus avoiding an electronic or optical transmitter for each user. The optimal characteristics of the LCOS device are calculated in terms of pixel number and silicon area and found to be feasible with today's technology. Finally, its performance in terms of optical efficiency and number of output ports is evaluated and found suitable for a neighborhood with hundreds of households.     

A novel silicon nanotips antireflection surface for the micro Sun sensor

We have developed a new technique to fabricate an antireflection surface using silicon nanotips for use on a micro Sun sensor for Mars rovers. We have achieved randomly distributed nanotips of radii spanning from 20 to 100 nm and aspect ratio of approximately 200 using a two-step dry etching process. The 30 degrees specular reflectance at the target wavelength of 1 microm is only about 0.09%, nearly 3 orders of magnitude lower than that of bare silicon, and the hemispherical reflectance is approximately 8%. When the density and aspect ratio of these nanotips are changed, a change in reflectance is demonstrated. When surfaces are covered with these nanotips, the critical problem of ghost images that are caused by multiple internal reflections in a micro Sun sensor was solved.     

微纳米结构硫酸钡的仿生合成与表征

以天然棉花和棉布作为生物模板成功制备了具有棉花和棉布纤维形貌的微纳米BaSO4晶体.研究了反应物浓度、反应温度、超声时问等因素对所得产物形貌的影响,确定了最佳反应条件.并用SEM、IR、XRD对最佳反应条件所得产物进行了表征.     

微纳晶体材料体膨胀系数测定和计算方法

为解决微纳尺度晶体材料膨胀系数无法直接测量的现状,文章提出一种适用的测试思路及计算方法.该方法基于材料在不同温度下的XRD衍射图谱获得晶胞晶格常数,通过"晶格常数-温度"拟合,计算各个物相晶轴的线膨胀系数,进一步计算获得材料的体膨胀系数.采用该方法对单相高锡焊料及多相PbSn合金焊球进行测试,获取其体膨胀系数,证实方法...     

The vacuum packaging of a flat lamp using thermally grown carbon nano tubes

In this work, we fabricate 1-in carbon nano tubes (CNTs) flat lamp of diode and triode structure. The CNTs have been directly grown on soda-lime glass substrate by thermal growth method. To know the optimized flat lamp structure, we have simulated the electric field distribution in these structures by the Maxwell simulator. The metal-mesh grid is inserted between an anode and cathode plate for dispersion of emitted electrons and decrease of turn-on voltage, and we investigate the trajectory of emitted electrons in the triode structure. Also, we suggest the direct joint packaging method, which needs no exhausting hole and tube. The CNTs flat lamps are successfully packaged and fully emitted with high brightness. The emission and brightness properties of CNTs are investigated for various conditions.     

Low-k film damage-resistant CO chemistry-based ash process for low-k/Cu interconnection in flash memory devices

In this paper, CO chemistry-based ash processes have been suggested to reduce carbon depletion and moisture absorption from plasma discharges for low-k/Cu interconnection in 40 nm-node Flash memory. We analyzed ash processes utilizing Fourier transform infrared spectroscopy (FTIR), k-value measurements, and sidewall-shrinking profile measurements based on a cross-sectional scanning electron microscope (SEM) image obtained before and after filling trench with Cu. In an effort to better understand the role of ash processes in ultra-narrow capacitors, we also evaluated the distribution of breakdown voltages as a function of voltage for trench-patterned wafers. In this paper, we successfully found that low-damage ash processes for low-k/Cu interconnection by adopting CO chemistry-based ash process.     

具有微/纳多孔结构的海胆状NiO的制备及其比容量研究

以六水合氛化镍和尿素为原料,利用水热合成法制备了具有徽/纳多孔结构的海胆状NiO的前驱物,经热处理后得到了具有微/纳多孔结构的海胆状NiO微球.通过XRD,SEM,H RTRM和N2-吸附-脱附对制得的NiO微球进行了表征,结果显示表面具有5-20nm微孔的海胆状NiO微球由许多直径3040nm的纳米线组装而成,其比表...