n-GaN基Ti/Al/Ni/Au的欧姆接触高温特性

研究了在高温工作环境下Ti/Al/Ni/Au(15nm/220nm/40nm/50nm)四层复合金属层与n-GaN的欧姆接触的高温工作特性.退火后样品在500℃高温下工作仍能显示出良好的欧姆接触特性;接触电阻率随测量温度的增加而增大,且增加幅度与掺杂浓度有密切关系.掺杂浓度越高,其接触电阻率随测量温度的升高而增加越缓慢;重掺杂样品的Ti/Al/Ni/Au-n-GaN欧姆接触具有更佳的高温可靠性;当样品被施加500℃,1h的热应力后,其接触电阻率表现出不可恢复性增加.     

n-GaN基Ti/Al/Ni/Au的欧姆接触高温特性

研究了在高温工作环境下Ti/Al/Ni/Au(15nm/220nm/40nm/50nm)四层复合金属层与n-GaN的欧姆接触的高温工作特性.退火后样品在500℃高温下工作仍能显示出良好的欧姆接触特性;接触电阻率随测量温度的增加而增大,且增加幅度与掺杂浓度有密切关系.掺杂浓度越高,其接触电阻率随测量温度的升高而增加越缓慢;重掺杂样品的Ti/Al/Ni/Au-n-GaN欧姆接触具有更佳的高温可靠性;当样品被施加500℃,1h的热应力后,其接触电阻率表现出不可恢复性增加.     

PLD法制备ZnO薄膜的退火特性和蓝光机制研究

通过脉冲激光沉积(PLD)方法,在O2中和100～500℃衬底温度下,用粉末靶在Si(111)衬底上制备了ZnO薄膜,在300℃温度下生长的薄膜在400～800℃温度和N2氛围中进行了退火处理,用X射线衍射(XRD)谱、原子力显微镜(AFM)和光致发光(PL)谱表征薄膜的结构和光学特性。XRD谱显示,在生长温度300℃时获得较好的复晶薄膜,在退火温度700℃时获得最好的六方结构的结晶薄膜;AFM显示,在此退火条件下,薄膜表面平整、晶粒均匀;PL谱结果显示,在700℃退火时有最好的光学特性。     

退火对N离子注入ZnO:Al薄膜性能的影响

利用溶胶-凝胶法在(0001)Al2O3衬底上制备了Al/Zn原子比为1%的ZnO:Al薄膜,将能量56keV、剂量1×1017ions/cm2的N离子注入到薄膜中.离子注入后,样品在500～900℃氮气气氛中退火,利用X射线衍射(XRD)、光致发光(PL)、透射谱和四探针研究了退火温度对薄膜性能的影响.结果显示,在800℃以下退火,随退火温度提高,薄膜结晶性能逐渐变好;在600℃以上退火,随退火温度提高,紫外近带边发光峰(NBE)和缺陷相关的深能级可见光发光带都逐渐增强;600℃退火时,样品的电阻率仅为83Ω·cm.     

高温退火对GDa-Si_xC_(1-x):H 薄膜晶化特性的影响

对GDa-Si_xC_(1-x):H膜进行高温退火,当退火温度在550℃附近时晶化开始,随退火温度升高晶粒尺寸和晶化范围增大.晶化后的a-Si_xC_(1-x):H膜光吸收系数、光学带隙和电导激活能下降,室温电导率增加.     

高温退火对GDa-Si_xC_(1-x):H薄膜晶化特性的影响

对GDa-Si_xC_(1-x):H膜进行高温退火,当退火温度在550℃附近时晶化开始,随退火温度升高晶粒尺寸和晶化范围增大.晶化后的a-Si_xC_(1-x):H膜光吸收系数、光学带隙和电导激活能下降,室温电导率增加.     

退火温度对电子束沉积Ag/TiO2薄膜光学性质和光催化性能的影响

研究了退火温度对电子束制备Ag/TiO₂薄膜光学 性质和光催化性能的影响。在石英玻璃、硅片 上沉积了Ag/TiO₂复合薄膜,在空气氛围下,进行了400℃, 500℃的退火一小时.用紫外-可见分光光度 计、X射线衍射仪(XRD) 、原子力显微镜(AFM)对沉积和退火后的薄膜分别进行光学、结构、 形貌分析。结 果表明:300℃下制备的Ag/TiO₂复合薄膜为无定形结构,400℃以上薄呈多晶态。吸光度和表面粗糙度 随退火温度的增加而增大,薄膜的光学带隙随退火温度的增加而减小。锐钛矿相表现出了更 好的光催化性能。     

退火温度对Cr-Si压阻薄膜电性能的影响

采用射频磁控溅射法在氧化铝陶瓷基底上制备了Cr-Si-Ni-Ti压阻薄膜,研究了不同退火温度对薄膜电性能的影响.结果表明:在溅射态及退火温度低于600℃时,薄膜为非晶态.随着退火温度的升高,薄膜的电阻温度系数(TCR)逐渐增大,应变因子(GF)先增大后减小,室温电阻率(ρ)则逐渐降低.在退火温度为300℃时,Cr-Si...     

退火温度对Ga掺杂SnO_2薄膜结构和光致发光特性的影响

利用电子束蒸镀在石英玻璃上制备出Ga掺杂的SnO_2(SnO_2∶Ga)薄膜。结合X射线衍射仪、原子力显微镜、紫外-可见-近红外分光光度计和光致发光谱,研究了不同退火温度对薄膜的结构与发光特性的影响。研究结果表明:当退火温度超过500℃,薄膜呈现四方金红石结构,随着退火温度的提高,晶粒尺寸增大,薄膜的禁带宽度变宽,发光强度逐渐增加,成功制备出发蓝紫光的SnO_2∶Ga薄膜。薄膜样品在700℃下退火后光致发光强度显著增强,这是因为随着退火温度的升高,SnO_2∶Ga薄膜的非辐射中心减少,有利于发生辐射复合。     

快速退火对SiGe/Si多量子阱p-i-n光电二极管的影响

利用光电流谱,结合X射线双晶衍射研究了快速退火对Si1-xGex/Si多量子阱p-i-n光电二极管的影响.由于应变SiGe的部分弛豫和Si-Ge互扩散,退火后的二极管的截止波长有显著的减小. 但是,在750-850℃范围内,波长蓝移量随着退火温度的增加而变化缓慢,而样品的光电流强度却随温度是先减弱而后又增强,这可能主要是由于在不同温度退火过程中失配位错的产生和点缺陷的减小造成的.     

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.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

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