图形化氧化锌阵列的制备及其场发射性能研究

为了减小场发射的屏蔽效应,采用图形化技术对氧化锌(ZnO)纳米枝阵列进行调控,并研究图形化ZnO枝阵列的性能。首先采用光刻法在ITO导电玻璃上制备图形化ZnO种子层,再用电沉积法在图形化种子层上生长ZnO纳米枝阵列。利用扫描电子显微镜(SEM)、X射线衍射(XRD)研究所制备的图形化ZnO阵列形貌、结构等,并测试其场发射性能。研究结果表明,制备的图形化ZnO纳米枝是圆阵列,直径为330μm左右,纳米ZnO主干平均直径为400~500nm,发现主干上有一些精细的类似锥状的纳米量级微细枝结构,并且具有良好的场发射性能,开启场强为2.15V/μm,场增强因子为16 109。该图形化生长ZnO阵列阴极的方法是一种能较好改善材料场发射性能的方法,在场发射应用领域表现出较好的前景。     

ZnO纳米线的快速生长机理及其场发射性能研究

为了快速制备具有优良场发射性能的ZnO纳米线,对ZnO纳米线的生长机理及场发射性能进行研究。首先采用优化的两步法制备出高长径比的ZnO纳米线,其次采用SEM对ZnO的微观形貌进行表征,然后,在分析形貌特点的基础上,说明了强碱体系下ZnO纳米线薄膜的快速生长机理。最后,对典型样品的场发射性能进行了测试。测试果表明,优化后的两步法,只需3h即可获得直径为40~50nm,长度为2.2~2.7μm,长径比高达54的纳米线。薄膜的开启电场为3.6V/μm,阈值场强为9.1V/um,场增强因子β高达3 391。研究表明,高pH值溶液可以加快ZnO纳米线沿C轴方向的择优生长,获得高长径比的ZnO纳米线,进而获得优良的场发射性能。     

衬底温度对氧化锌薄膜场发射性能的影响

利用射频磁控溅射法制备了不同衬底温度的氧化锌(ZnO)薄膜.研究了其场发射特性,分析了场发射特性和衬底温度的变化关系.实验结果表明, 开启电场随着衬底温度的增加呈先增大后减小的趋势,场发射特性的变化是由于衬底温度的改变引起表面形貌的变化所致.衬底温度为300 ℃时沉积的ZnO薄膜样品粗糙度最小,场发射性能最差,其开启场强为1.7 V/μm,场强为3.8 V/μm时电流密度仅为0.001 97 A/cm2;衬底温度为400 ℃时沉积的ZnO薄膜样品表面粗糙度最大,场发射特性也优于其他薄膜;开启场强为0.82 V/μm, 场强为3.8 V/μm时电流密度稳定在0.03 A/cm2.Fowler-Nordheim(F-N)曲线为直线表明, 电子是在外加电场的作用下隧穿表面势垒束缚发射到真空的.     

氧化钨纳米结构：可控制备及场发射性能

通过简单调控化学气相沉积反应气压制备了形貌尺寸可控的各种非化学计量比氧化钨纳米结构。场发射研究表明W18O49纳米线具有优异的场发射性能。对于10 μA/cm2的发射电流,其开启电压为7.1 V/μm。 实验中测得最高场发射电流密度4.05mA,对应场强为17.2 V/μm。场发射过程中的热蒸发和脱附测试表明该氧化钨纳米线的场发射再现性很高。     

电泳法制备四针状纳米ZnO场发射阴极

用电泳法成功地将四针状纳米ZnO沉降在透明导电玻璃ITO衬底上,制备出13cm×10cm面积的场发射阴极屏。使用扫描电子显微镜观察ZnO颗粒的表面形貌及分散均匀性。结果表明电泳法制得的ZnO场发射阴极屏透明且颗粒分布较均匀。讨论了电泳电压、沉降时间、电泳液浓度对阴极场发射电流的影响,通过实验得出用电泳法转移四针状纳米氧化锌制作阴极屏的最佳工艺条件,即直流电压75V、电泳时间为8min,两极距离2.5cm条件下制得的屏场发射性能较佳,显示效果较好。测试了ZnO阴极屏在1200V直流电压下长时间发射稳定性,测试过程电流波动范围小于5%。实验表明采用电泳法制备场发射阴极具有工艺简单、步骤少、易操作、成本低并能根据需要控制薄膜厚度及场发射屏面积等优点,对于大屏幕、低成本FED的研发具有实际应用意义。     

热敷法制备丝状阴极及其在场发射中的应用

采用热敷法将碳纳米管(CNT)浆料直接热敷在Ni丝上制备成丝状阴极,并在圆柱形灯管中采用二极结构测试其场发射性能.扫描电镜(SEM)测试表明,丝状阴极的表面有一层均匀的CNT材料;场发射结果表明,CNT-Ni丝状阴极与传统的场发射阴极相比具有更优良的场发射性能,开启电场为0.15 V/μm,当电压为2280V时发射电流达到4 mA.在腔体中测试其发光亮度,最高值达到了14000 cd/m2.     

热CVD法制备的碳纳米管线阵列的场发射特性

采用半导体光刻技术在硅衬底上获得图形化掩膜,然后用热化学气相淀积(T-CVD)的方法制备了图形化的碳纳米管线阵列,用扫描电镜和拉曼光谱仪对碳纳米管进行了表征.研究了图形化碳纳米管线阵列的场发射特性,并与无图形化处理的碳纳米管薄膜样品的场发射特性进行了比较.当发射电流密度达到10 μA/cm2时,无图形化处理的碳纳米管薄膜、10 μm碳纳米管线阵列以及2 μm碳纳米管线阵列样品的开启电场分别为3 V/μm、2.1 V/μm和1.7 V/μm;而当电场强度达3.67 V/μm时,相应的电流密度分别为2.57 mA/cm2、4.65 mA/cm2和7.87 mA/cm2. 实验结果表明,图形化处理后的碳纳米管作为场发射体,其场发射特性得到了明显的改善.对改善的原因进行了分析和讨论.     

图案化氧化钨纳米线阵列的低温制备工艺及其场发射特性研究

氧化钨纳米线由于具有长径比较大、导电性好、阈值电场较低、可承受的电流较高等优点,因此在场致电子发射器件中受到人们的广泛关注。但是在氧化钨纳米结构研究发展的过程中,出现了一些技术难题,比如制备温度高(>800℃),制备的氧化钨通常混合多种化学相而导致物性不均匀等,所以束缚了氧化钨纳米线在场发射领域的快速发展。本文采用磁控溅射技术结合化学气相沉积技术在500℃下分别实现了高纯相的WO2和WO3纳米线阵列的定域生长。场发射特性研究结果表明:所制备的WO3纳米线阵列的开启电场低至0.65MV/m,阈值电场约为2.9MV/m,最大电流密度达到18.3A/cm2;WO2纳米线阵列的开启电场低至0.8MV/m,阈值电场为2.46MV/m,最大电流密度达到12.1mA/cm2。这表明在低温下制备的氧化钨纳米线阵列在场致电子发射领域具有非常广阔的应用前景。     

电流法改善碳纳米管阴极场发射特性

针对丝网印刷碳纳米管阴极,提出电流法进行表面后处理,有效改善碳纳米管阴极场发射特性.利用扫描电子显微镜表征电流法处理前后CNTs阴极表面形貌变化,并对处理前后CNTs阴极进行场发射特性测试.结果表明,电流法处理后CNTs阴极表面残留有机物被破坏,开启电场从2.4 V/μm降低到1.6 V/μm,同样面积的薄膜(印制面积为1 cm×1 cm)在2.6 V/μm场强下的发射电流由30 μA提高到了800 μA,说明电流处理对于提高薄膜的场发射特性有明显作用.该方法在碳纳米管场发射显示器的制作中具有很好的实际应用价值.     

ZnO纳米棒的图形化生长及其场发射特性

介绍了用氢离子注入技术和阳极腐蚀方法在硼掺杂p-(100)型硅晶片上制备图形化的纳米硅(SiNC)薄膜工艺,并在这种图形化衬底上成功生长了图形化的ZnO纳米棒.场发射测试表明制备的ZnO纳米棒具有良好的场发射性能,即具有较低的开启电场和阈值电场,较高的发射点密度.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks     

Call for Papers—Feature Topic,Vol.12,No.7,2015

正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first