Eu3+,Li+共掺杂ZnO薄膜结构与发光性质的研究

为了研究Eu3+,Li+共掺杂的ZnO薄膜结构与发光性质,采用脉冲激光沉积方法在P型单晶Si（111）衬底上制备了Eu3+,Li+共掺杂的ZnO薄膜,其中,Eu3+作为发光中心,而Li+作为低价电荷的补偿离子和发光敏化剂。分别对样品进行了X射线衍射谱测试和光致发光谱分析。得出的数据中X射线衍射谱显示,Eu3+,Li+共掺杂的ZnO薄膜具有c轴择优取向,X射线衍射谱中除ZnO晶向以外没有出现其它结晶峰;Eu3+,Li+共掺杂的ZnO薄膜的光致发光谱与ZnO纯晶体薄膜的发射光谱基本相似,但是掺杂ZnO薄膜的紫外发光峰却出现红移现象,峰值位于382nm处,且发光峰也不尖锐。当以395nm的激发光照射样品时,在光致发光光谱中观察到了稀土Eu3+在594nm,613nm附近的特征发光峰。结果表明,掺杂元素Eu3+,Li+均已进入到ZnO晶格中,形成了以Eu3+为发光中心的ZnO纤锌矿结构。     

Ga-N共掺氧化锌纳米线阵列制备及发光性能研究

采用化学气相沉积法（CVD）以一氧化氮（NO）和氧化镓（Ga2O3）为掺杂源,在c轴取向单晶蓝宝石衬底上外延生长镓氮（Ga-N）共掺氧化锌（ZnO）纳米线阵列。利用SEM, XRD, HRTEM, XPS, PL等测试手段对掺杂后的ZnO纳米线阵列进行结构、成分和光学性能表征。结果表明,Ga-N共掺ZnO纳米线阵列保持六方纤锌矿结构,沿（002）方向择优生长;掺杂元素在样品中均匀分布。随着掺杂浓度增加,纳米线由六棱柱结构转变为尖锥层状结构,长度由2 μm减小到1 μm,锥度增加至0.95;N 1s/Ga 2p/Zn 2p峰结合能向低能态方向移动。PL光谱分析表明,所有样品均出现紫外发光峰和绿光发光峰,不同掺杂浓度的缺陷发光强度不同。     

自催化方式制备ZnO纳米线及光致发光特性

采用化学气相沉积法,不用催化剂,在Si(111)基片上制备了ZnO纳米线。扫描电子显微镜(SEM)表征发现ZnO纳米线的直径在100nm左右。X射线衍射(XRD)图谱上只存在ZnO的(002)衍射峰。室温下光致发光谱(PL)中出现了389nm和357nm的紫外峰以及五个蓝光峰(450,468,474,481和491nm)。389nm峰为自由激子复合发射357nm峰是在LO声子的参与下,自由载流子碰撞形成自由激子过程的发光行为;468nm峰系电子从氧空位形成的浅施主能级向价带跃迁发光;450nm峰系电子从导带向锌空位形成的浅受主能级跃迁发光;474,481和491nm峰是声子伴线。     

Li、Mg掺杂ZnO薄膜PL特性研究

采用溶胶-凝胶法在玻璃基片上制备了Li、Mg掺杂的ZnO薄膜,研究了薄膜的光致发光(PL)性能。结果表明,由氧缺位引起的深能级发光峰(450~470 nm)的强度随Li和Mg掺杂量的增加而下降。Mg的添加会使薄膜的带边发射(NBE)增强,而Li的掺杂抑制了NBE峰,同时引发403 nm的Li杂质能级峰,该能级位于价带顶0.29 eV处。     

ZnO纳米线的低温生长及其发光特性

采用电场辅助电化学沉积的方法在阳极氧化铝模板中沉积出ZnO纳米线阵列.透射电子显微镜和X射线衍射测试结果表明,制备的纳米线是单晶ZnO纳米线,形貌均匀,直径大约为60nm,并且择优于(101)晶面.对生长过程中所加的辅助电场的作用给出了初步解释.光致发光谱表明,在350～650nm范围内存在一个很宽的发光峰.     

ZnO纳米线的低温生长及其发光特性

采用电场辅助电化学沉积的方法在阳极氧化铝模板中沉积出ZnO纳米线阵列.透射电子显微镜和X射线衍射测试结果表明,制备的纳米线是单晶ZnO纳米线,形貌均匀,直径大约为60nm,并且择优于(101)晶面.对生长过程中所加的辅助电场的作用给出了初步解释.光致发光谱表明,在350～650nm范围内存在一个很宽的发光峰.     

ZnO：Ag薄膜的结构对其紫外发光增强的研究

利用脉冲激光沉积方法(PLD),在Si(100)衬底上生长了银掺杂的氧化锌薄膜(ZnO:Ag),所用的激光波长分别是1064 nm和355 nm.通过x射线衍射分析发现,两种不同激光沉积样品的晶体结构有很大的区别.此外,由1064 nm激光制备的ZnO:Ag薄膜,在氧气中800℃的条件下退火一个小时后,在其光致发光(PL)谱中发现,样品的紫外发光峰强度随薄膜中Ag含量增加而急剧增强,但在同样条件下处理的由355 nm激光制备的薄膜,没有观察到类似现象.经过分析和比较,我们认为这种紫外发光增强的特殊现象,是ZnO:Ag薄膜中的纳米Ag颗粒所引起的局部等离子共振而导致.     

稀土Er掺杂的MoSe2纳米线的制备及发光特性研究

本文研究了稀土掺杂硒化钼(MoSe₂)垂直纳米线 的制备及光学特性。以分析纯硒化钼 粉末为原料,采用热蒸发方法在Si衬底上沉积硒化钼垂直纳米线,并在其生长过程中利用硝 酸鉺进行原位掺杂。利用原子力显微镜(AFM)、X射线衍射仪(XRD)、紫外-可见分光光度计 和 荧光光谱仪研究了掺杂硒化钼薄膜的表面形貌﹑晶体结构﹑光吸收和特性。发现掺杂后MoSe ₂纳米线的结晶性更强,长度增加2倍以上。同时,掺杂后纳米线的可见光吸收和光致发光 强 度明显增强,760 nm处MoSe₂纳米线的带间跃迁的本征发射增强4倍 以上。另外,Er³⁺掺杂后 ,在590 nm和650 nm处增加了2个来自Er³⁺离子的发射,说明稀土掺杂后发光峰增加,使 光谱谱线更加丰富。以上结果表明,稀土掺杂可显著增强硒化钼的结晶性、光吸收和发光效 率,使其可用于制备超薄、高效率的太阳能电池、光探测器等光电子器件。     

p型掺杂ZnO薄膜的光致发光特性研究

采用磁控溅射技术,以N2作为p型掺杂源,制备p型N掺杂ZnO薄膜,着重研究了不同掺杂量的N掺杂ZnO薄膜的光学特性。结果表明,掺杂ZnO薄膜在360 nm、380 nm处出现主荧光峰,409 nm、440 nm处出现次荧光峰,而且随着N掺杂量的不同,主、次荧光峰 峰位和强度都会发生变化。当O2∶N2的体积流量比为15∶5时,薄膜中N含量最大,荧光谱中发光峰强度最佳,霍尔效应检测薄膜具有明显的p型导电特征。     

(Ni、Li)掺杂ZnO薄膜的制备及其性能

采用溶胶-凝胶技术和旋涂的方法,在Si(100)衬底上制备了Ni掺杂和(Ni、Li)共掺的3种ZnO薄膜(Ni0.10Zn0.90O、Ni0.10Li0.05Zn0.85O和Ni0.10Li0.10Zn0.80O)。X射线衍射分析表明,所有薄膜样品均为纤锌矿结构,未发现其他杂相。光致发光研究表明,(Ni、Li)共掺后出现了410nm左右的紫外发光峰,并随Li浓度的增加发光峰变强,该峰与Li杂质能级有关,同时观察到O2-空位引起的610nm和740nm的两个红色发光峰。薄膜中Ni离子为+2价,取代Zn离子的位置。掺杂的ZnO薄膜呈现室温铁磁性,单个Ni原子的饱和磁矩可达到0.210μB,掺入Li或在N2气氛中退火后,都导致单个Ni原子的饱和磁矩降低。铁磁性来源于电子调制的机制。     

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.     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

Complete approach to automatic identification and subpixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

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.     

A Versatile Mixed-Signal Pin Approach for Cost-Effective Test of Automotive ICs

Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.     

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.     

Optical vibration and deviation measurement of rotating machine parts

It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer （LDV）.     

社长序言（英文）

正Happy New Year!As we step into a new year,we take a look back at the key feature topics covered in China Communications over the past 12 months and set out our expecta-