发光二极管领域发展分析

介绍发光二极管的性质、应用及发光原理,根据专利数据库中的专利数据及国际专利分类体系对发光二极管领域的专利申请进行专利分析,对发光二极管近10年的专利申请量、技术脉络以及改进专利进行梳理,为国内发光二极管领域的发展提供分析依据.     

表面等离子体提高GaN-LED发光效率的研究进展

表面等离子体能够增强氮化镓发光二极管的发光效率,为高效发光二极管芯片的研究提供了可行的方案。近年来,国内外研究小组在利用表面等离子体增强氮化镓发光二极管发光效率的实验中,取得了很多有价值的结果。介绍了具有金属薄膜、金属颗粒和金属光子晶体等典型结构的氮化镓发光二极管。重点探讨了表面等离子体增强发光二极管发光的机理、结构和关键技术。对具有二维金属光子晶体的氮化镓发光二极管发光增强机理进行了分析和预测,认为利用二维光子晶体可以从内量子效率和外量子效率两方面增强器件发光,并且有很好的可控制性,是提高发光效率的可行方案。     

未来照明发光二极管

据莫斯科国立罗蒙诺索夫大学阿．艾．尤诺维奇报导，七年以前，俄刊《照明技术》杂志公布了作者关于新一代氮化镓及其固溶体高效发光二极管性质评述的文章。文中详细介绍了发光二极管在不同照明技术领域广泛应用的前景。那时觉得未来用发光二极管取代广用白炽     

MOCVD技术

金属有机物化学气相淀积(Metal Organic Chemical Vapor Deposition, 简称 MOCVD)自 20 世纪 60 年代首次提出以来,经过 70 年代至 80 年代的发展,90 年代已经成为砷化镓、磷化铟等光电子材料外延片制备的核心生长技术,特别是制备氮化镓发光二极管和激光器外延片的主流方法。到目前为止,从生长的氮化镓外延片和器件的性能以及生产成本等主要指标来看还没有其它方法能与之相比。MOCVD技术     

宽禁带GaN基半导体激光器进展

宽禁带Ⅲ族氮化物基半导体是20世纪末研究最活跃的半导体材料系,其高亮度发光二极管和激光器一出现即以惊人的速度实现了商品化。文章就GaN基半导体激光器的市场需求、蓝宝石基片上生长的氮化镓基激光器的研制和发展概况以及近期研究热点作了扼要介绍。     

激光钻孔技术对氮化镓LED特性的影响

研究利用激光钻孔技术应用于氮化镓发光二极管,是利用高能激光束将蓝宝石基板打出孔洞,并在孔洞内壁蒸镀金属层薄膜,藉以利用金属导热良好的特性,将表面热能传导至基板,并利用封装技术配合,使得热能顺利从底座散去,降低热效应带来的影响.通过实验获得:在注入电流700 mA下,打孔较未打孔的氮化镓发光二极管,光输出功率增加约77％...     

非平面化型ITO氮化镓基蓝光发光二极管

将氧化铟锡(ITO)生长于氮化镓基蓝色发光二极管的出光台面上(p型GaN台面),用非平面化处理的方法制作出ITO井状结构,研制出非平面化型氧化铟锡-氮化镓基蓝色发光二极管(LED),获得了高的出光效率.结果表明,在20mA工作电流下,该蓝色发光二极管的出光光强是平整的普通ITO-GaN基LED的1.35倍.     

欧司朗成功在硅衬底上制程GaN LED芯片

正欧司朗光电半导体公司的研究人员经过研究,现已成功在硅衬底上生产出了氮化镓LED芯片,取代了目前普遍使用的较为昂贵的蓝宝石衬底。这种新的制造技术有望大幅降低发光二极管(LED)的生产成本,进一步推动其普及进程。硅是一种标准半导体材料,作为LED衬底具有尺寸大、成本低、易加工、导电好等优异性能。但技术难点在于硅与氮化镓的热膨胀系数不同,在制造过程     

三菱化学开拓GaN基板用途用以开发氮化镓外延片

三菱化学积极扩展白光LED事业,并以强化氮化镓相关事业为发展的一环。三菱化学的氮化镓基板,除了用于该公司自制的白色发光二极管(LED)灯泡之外,企图开拓用途以预计今后需求将大增的投影用超小型至大型的高效率     

有机电致发光二极管中国专利申请现状分析

随着显示技术的发展,体积小、重量轻、功耗低的显示器件有机电致显示成为显示技术的发展重点,介绍了有机电致发光二极管OLED的发展历程,并以有机电致发光二极管在国内外专利申请的数据为分析样本,从有机电致发光二极管专利申请的时间、国家、技术概况等角度进行研究,分析了有机电致发光二极管的技术发展现状以及将来的发展趋势.     

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.     

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.     

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.     

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.     

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.