激光能量对脉冲激光沉积法制备ZnO薄膜性能的影响

脉冲激光沉积技术(PLD)易于获得高质量的氧化物薄膜已成为一种重要的制备ZnO薄膜的技术.采用脉冲激光沉积(PLD)(KrF准分子激光器:波长248 nm,频率5 Hz,脉冲宽度20 ns)方法在氧气气氛中以高纯Zn(99.999%)为靶材、在单晶硅和石英衬底表而成功生长了ZnO薄膜.通过X射线衍射仪、表面轮廓仪、荧光光谱仪、紫外可见分光光度计对合成薄膜材料的晶体结构、厚度、光学性质等进行了研究,分析了激光能量变化对其性能的影响.实验结果表明我们使用PLD法可以制备出(002)结晶取向和透过率高于75%的ZnO薄膜,激光能量为450 mJ的ZnO薄膜的发射性能较好,但激光能量的增加不能改善薄膜的透光率.     

PLD法制备ITO导电薄膜及其性能

为了研制可用于高温环境下进行应变测量的应变层,采用脉冲激光沉积(PLD)法在陶瓷基底上制备了氧化铟锡(ITO)薄膜.研究了PLD法中不同基底温度对ITO薄膜显微结构、电学性能以及阻温特性的影响.采用X射线衍射仪(XRD)测试了薄膜的晶体结构,通过四点探针测量法测得薄膜的薄层电阻,采用场发射扫描电子显微镜(FESEM)对...     

有机玻璃衬底磁控溅射ITO膜的制备与性能研究

在低温条件下采用直流磁控溅射法在有机玻璃(PMMA)衬底上制备了ITO薄膜。分别采用分光光度计、四探针测试仪研究了底涂层、衬底温度、氧流量、溅射时间对PMMA上沉积的ITO薄膜性能的影响。研究结果表明:涂覆底涂层有助于ITO成膜;衬底温度影响薄膜的方块电阻值;适当增大O2流量可以提高薄膜的透射率,但过高的O2流量降低薄膜的导电性;溅射时间延长,方块电阻值减小。优化工艺后制备的ITO薄膜为非晶态膜,可见光平均透过率达83.5%,方块电阻为22Ω/□。     

有机玻璃衬底磁控溅射ITO膜的制备与性能研究

在低温条件下采用直流磁控溅射法在有机玻璃(PMMA)衬底上制备了ITO薄膜。分别采用分光光度计、四探针测试仪研究了底涂层、衬底温度、氧流量、溅射时间对PMMA上沉积的ITO薄膜性能的影响。研究结果表明: 涂覆底涂层有助于ITO成膜; 衬底温度影响薄膜的方块电阻值; 适当增大O2流量可以提高薄膜的透射率, 但过高的O2流量降低薄膜的导电性; 溅射时间延长, 方块电阻值减小。优化工艺后制备的ITO薄膜为非晶态膜, 可见光平均透过率达83.5%, 方块电阻为22Ω/□。     

射频磁控溅射法沉积透明柔性导电CdO薄膜

随着透明电子器件和柔性显示器的发展,柔性透明导电薄膜正在受到越来越多的关注.采用射频磁控溅射法在柔性衬底上低温沉积高透过率、低电阻率的CdO薄膜.研究了O2流量对薄膜的结晶性能、光学性质和导电性能的影响.研究结果表明,室温下沉积的CdO薄膜均为结晶性能良好的立方结构薄膜,(200)取向性明显.另一方面,O2流量对CdO薄膜的光电性能有很大的影响.O2流量过小时,薄膜的透光率较差,而当O2流量较大时,薄膜的电阻率较大,当O2流量大于3 cm3/min时,光学透光率不再有大的变化.     

ITO薄膜的电阻并联效应研究

采用电子束蒸发镀膜方法在K9玻璃基底上分别镀制了ITO/SiO₂/ITO,ITO/Ti₂O₃/ITO和ITO/MgF₂/ITO结构的多层薄膜,用四探针方块电阻仪测量薄膜表面的方块电阻,用原子力显微镜观测样品的表面微观形貌。结果显示,当ITO薄膜的粗糙度较大且介质薄膜的物理厚度小于100nm时,各层ITO薄膜之间通过山峰状的凸起结构相连通,导致样片表面的方块电阻测量值与各层ITO薄膜电阻的并联值相当。这表明,当ITO薄膜的粗糙度较大且介质薄膜厚度较小时,各层ITO薄膜表现出电阻并联效应。利用多层ITO薄膜的电阻并联效应设计并制备了450～1200nm超宽光谱透明导电薄膜,用四探针方块电阻仪测量了试验样片的表面方块电阻,用紫外-可见-近红外分光光度计测试了样片的光谱透射率。结果显示,在相同表面方块电阻条件下,相比于单层ITO薄膜,利用ITO薄膜电阻并联效应所制备的多层透明导电薄膜具有更高的光谱透射率。     

磁控溅射法制备ITO薄膜的结构及光电性能

本文采用直流磁控溅射法在基板温度1OO℃、100%Ar气氛中制备了光电性能优良的铟锡氧化物(In2O3:SnO2=90:10,质量百分比)薄膜.利用XRD、AFM、SEM、多功能光栅光谱仪和四探针电阻测试仪对薄膜的结构、表面形貌、透光率和方阻进行了测定和分析,研究了溅射功率对薄膜透光率的影响.结果表明:ITO薄膜的方阻随溅射功率的增加而下降;经过热处理,ITO薄膜可见光透光率从60.4%增加到88.3%;ITO薄膜在360 nm到380 nm的紫光区域透光率最低,760 nm到800nm的红光区域透光率达到最高.     

溶胶-凝胶法制备ITO薄膜的光电性能研究

采用溶胶-凝胶旋转涂膜工艺,在普通玻璃基片上制备了掺锡氧化铟(ITO)纳米透明导电薄膜。采用紫外-可见透射光谱和四探针技术,研究了不同Sn掺杂量、不同热处理温度和热处理时间以及不同涂层对薄膜光学和电学性能的影响。结果表明薄膜的方块电阻随Sn掺杂量的增大和热处理温度的升高先降低后增加,在适宜的温度范围内薄膜在可见光区平均透过率随热处理温度升高而增加。在一定的温度下,随着热处理时间的延长,ITO薄膜的方块电阻先降低后增加,透射率先增加后降低。在最佳工艺条件下,采用溶胶-凝胶法制备的ITO薄膜平均可见光透过率达86%,薄膜方阻为322Ω/□。     

ZnO∶Al替代ITO作透明导电膜的应用

研究了AZO(ZnO∶Al)替代ITO透明导电膜在GaN基LED中的应用,通过脉冲激光沉积和磁控溅射法制作了AZO薄膜,分析了AZO与p型GaN不良的欧姆接触的物理机理,并利用插入ITO薄层来改善接触电阻,实验用ITO 20nm/AZO 500nm的复合导电薄膜做透明导电薄膜,成功得到了波长为525.74nm、亮度为380.88mcd、电压为3.35V的GaN基绿光LED芯片,相当于单一ITO透明导电膜的性能,整个试验工艺中减少了ITO的使用量,降低了LED芯片的制造成本。     

不同衬底温度生长的La_(0.5)Sr_(0.5)CoO_3薄膜椭圆偏振光谱研究

采用脉冲激光沉积法(PLD)在不同Si(100)衬底温度下制备了La_(0.5)Sr_(0.5)CoO_3(LSCO)导电金属氧化物薄膜.X射线衍射(XRD)分析表明,随着衬底温度升高LSCO薄膜的结晶质量增加,在650℃和700℃下制备的薄膜是具有单一钙钛矿结构的多晶薄膜.通过椭圆偏振光谱仪测量了400～1100nm波长范围内该导电金属氧化物薄膜的光学性质,采用双Lorentz振子色散关系及三相结构模型(Air/LSCO/Si)拟合获得了薄膜的光学常数.结果表明,薄膜的折射率随着衬底温度的升高而减小,然而在可见-近红外波长范围内消光系数随着衬底温度的升高而增大.这主要与薄膜的晶化质量和导电性能有密切的关系.     

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.     

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.     

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.     

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.     

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     

JOURNAL OF ELECTRONICS(CHINA)

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NEXT GENERATION WIRELESS NETWORKS–ESPECIALLY THE USE OF MILLI-MICROWAVE BANDS

The global bandwidth shortage of wireless communications has motivated the exploration of the naillimeter wave （ram-wave） frequency spectrum for the next generation wireless communications. Recent advances in RF CMOS technology and high speed baseband signal processing technologies have enabled tile extensive research and development of turn-wave wireless communications. The multi gigabit per second data rate of ram-wave system will lead to applications in many important scenarios, such as WPAN, WLAN,back-haul for cellular system. And the frequency bands include 28 GHz, 38 GHz, 45GHz, 60GHz, E-BAND and even beyond 100 GHz. The propagation and the imitation of the RF circuits design in these frequency bands make the directional antennas be inevitable for mm-wave communications.