基于CuPc…C60的混合层异质结光伏器件性能研究

制备了基于CuPc…C60混合层异质结有机光伏器件,将其与CuPc-C60双层结构光伏器件进行对比研究。结果表明混合层结构器件性能得到改善,其开路电压、短路电流密度、填充因子和光电转换效率都有提高,分别从CuPc-C60双层结构器件的0.39V、1.92mA/cm2、0.36%、0.48依次提高到CuPc…C60混合层结构器件的0.48V、2.21mA/cm2、0.54%、0.51。根据整数电荷转移模型来分析光伏器件D/A界面及有机材料-ITO衬底界面特性,认为混合层异质结有机光伏器件给体材料HOMO与受体材料LUMO的能级差增加使得器件开路电压提高。混合层异质结有机光伏器件D/A界面面积增加和给体材料HOMO与受体材料LUMO的能级差增加都提高了激子的分离效率,所以器件的短路电流密度增加。     

Alq3作为激子阻挡层对有机太阳能电池的影响

选用CuPc(酞菁酮)为供电子的材料,Alq3(8-羟基喹啉铝)为激子阻挡层,研究了结构为ITO/CuPc(20 nm)/C60(40 nm)/Alq3(x)/Ag(100 nm)的有机太阳能电池(OPV),考察了OPV性能同阻挡层Alq3厚度之间的关系.通过分析发现,OPV效率同有机功能层厚度密切相关,在标准太阳光照条件下,结构为ITO/CuPc(20 nm)/C60(40 nm)/Alq3(x)/Ag(100 nm)的器件效率随着Alq3厚度的增加先增大后变小,当厚度为0 nm时,效率为0.285%;当厚度为2.5 nm时,效率为1.13%;而当厚度为5 nm时,效率为0.569%;当厚度为10 nm时,效率则为0%.     

有机电致发光的效率

描述了评价有机电致发光性能的重要指标－－发光效率问题,从发光机制考虑,一般常用外量子效率和内量子效率来评价。外量子效率是有机电致发光器件输出光子数与注入电子数之比;内量子效率是产生在器件内部的光子数与液入电子数之比,对于光子能否输出到器件外部无关紧要。评价器件性能还有一些其他效率评价方法,如能量效率,功率效率等,特别是外功率效率（1m/W),电流效率（cd/A)也常常用于表征有机电致发光性能,但它们与发光光谱的视觉灵敏度有关,对紫外外辐射器件不适用,另外,利用三重态激子发射可以提高EL器件效率,理论上可达100％,器件结构及材料对器件外量子效率影响至关重要。     

CuPc作蓝色OLED的缓冲层对器件性能影响的研究

本文对以LiBq，作为发光层，PVK：TPD作为空穴输运层，结构为：ITO／PVK：TPD／LiBq4／Alq3／Al的蓝色有机电致发光器件，在相同工艺条件下引入和不引入CuPc缓冲层，进行了实验研究。结果表明：由于CuPc缓冲层的引入，使蓝色OLED的电流随电压的增大较未加CuPc的OLED相对缓慢；且启亮电压上升，发光亮度和效率下降。这主要是因为CuPc加入后，空穴注入势垒降低，使PVK：TPD／LiBq4界面空穴积累数量增大，产生的反向漂移电场阻碍了空穴多数载流子的注入；并进而致使发光层注入空穴数量减小，内建电场加强，激子形成几率变小，解离几率增大。     

掺杂的有机薄膜的电致发光

制备了具有多层有机薄膜的电致发光(EL)器件。其基本结构由一个空穴输运层和一个发光层构成。空穴输运层为非晶二胺膜。在该层中,唯一可迁移的载流子是空穴。发光层由基质材料8-羟基喹啉铝(Al_q)构成,该层主要输运电子。在低于10V的电压驱动下可获得较强的光输出。与未掺杂的器件相比,在Al_q层中掺入具有强荧光的分子可以使器件的EI效率提高近2倍。具有代表性的掺杂物是香豆素(Coumarin)和DCM。掺杂器件的EL量子效率约为2.5％光子/电子。选择不同的掺杂物以及改变掺杂物的浓度可以容易地把EL器件的颜色从蓝绿调节到橙红区。在掺杂体系中,电子空穴复合和辐射区能被限制在距空穴输运界面50附近。在未掺杂的Al_q器件中,激子的扩散使其EL辐射区变得很大。多层掺杂的EL器件提供了一种直接测量激子扩散长度的方法。     

C_(60)作激子阻挡层的有机发光二极管

制备了结构为ITO/CuPc(25nm)/NPB(40nm)/Alq3(xnm)/C60(ynm)/LiF(1nm)/Al(100nm)的有机发光二极管(OLEDs),研究了C60插入层对器件性能的影响。结果表明,在无C60的器件中,当Alq3层较厚时,器件的电流密度-电压(J-V)曲线右移,不利于获得高功率效率;当Alq3层较薄时,又会导致激子在LiF/Al阴极的严重淬灭。实验优化得出,在无C60的器件中,Alq3厚为45nm的器件可获得最高的功率效率。在Alq3与LiF之间插入15nmC60层后,对器件的J-V曲线几乎没有影响,但C60层阻挡了激子向阴极扩散,减少了淬灭。当在Alq3厚度为45nm的器件的Alq3和LiF间插入15nmC60层后,可使器件获得更高的功率效率,尤其是插入15nmC并将Alq厚度降至30nm,获得了最大的功率效率。     

基于分布式布拉格反射器的量子点彩膜

通过研究量子点彩膜的转换效率、结构对出光强度和色域的影响,提出了基于分布式布拉格反射器的量子点彩膜新结构。首先通过光学仿真软件导入红/绿量子点参数并构建量子点彩膜光色转换模型,设置分布式布拉格反射器和传统滤光片的膜层属性;再以蓝光背光源激发量子点彩膜,研究膜层在不同膜厚和量子点比重的情况下蓝光利用率;最后,比较了传统彩色滤光片和分布式布拉格反射器两种结构对量子点彩膜光学性能的影响。设计结果表明:新结构比传统彩色滤光片结构红、绿子像素光强分别提升了2.19和2.26倍,在CIE1931-NTSC标准下可实现色域为128%。     

多层白色有机发光器件的结构和性能优化

以红、蓝、绿为基,制备了不同发光层组合次序的有机发光器件,研究了各发光层的顺序及厚度对器件性能的影响,并在此基础上构成了白色有机发光器件.通过改变关键发光层的厚度,来调节不同颜色之间的平衡,从而达到色度很好的向色;由于关键发光层的厚度很薄,因此得到的器件在高电压的色度漂移也很小.优化的白光器件在200 mA/cm2时,电流效率为3.78 cd/A,色坐标为x=0.345,y=0.323.根据激子产生和扩散理论,讨论了器件性能对于各发光层的厚度及激子扩散长度的依赖关系,拟合结果与实验结果吻合.     

InP系量子阱相位调制器的理论设计

本文应用量子限制Ｓｔａｒｋ效应理论计算了ＩｎＰ系量子阱中激子的波函数及激子的能量．在此基础上，计算了不同电场条件下激子能量的红移，以及吸收系数的变化．然后，根据Ｋ－Ｋ关系计算了折射率的变化，得到了一定强度外电场条件下，折射率变化与波长、组份及阱宽的关系．按照我们的计算，折射率变化可达２.５４e－２．     

In_xGa_(1-x)As/InP应变量子阱中激子跃迁能量随In组分的变化

本文研究了ＩｎｘＧａ１－ｘＡｓ／ＩｎＰ应变多量子阱中激子跃迁能量随Ｉｎ组分的变化．用国产ＧＳＭＢＥ设备生长了五个样品，这五个样品的阱宽均为５ｎｍ，垒宽均为２０ｎｍ，唯一的不同之处是阱层中的Ｉｎ组分不同，Ｉｎ组分从０．３９变化到０．６８．用Ｘ射线双晶衍射及计算机模拟确定出了各样品阱层中实际Ｉｎ组分．用光致发光谱（ＰＬ）、吸收谱（ＡＳ）、光伏谱（ＰＶ）确定出了样品中的激子跃迁能量．对量子阱中的激子跃迁能量随Ｉｎ组分的变化进行了理论计算．结果表明：对给定阱宽的量子阱，随着Ｉｎ组分的增大，量子阱中１１Ｈ和１１Ｌ激     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

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.