Sol-Gel法制备Bi_(3.15)Nd_(0.85)Ti_3O_(12)铁电薄膜

采用溶胶-凝胶(Sol-Gel)法在Pt/Ti/SiO_2/Si衬底上制备Bi_(3.15)Nd_(0.85)Ti_3O_(12)薄膜,发现制备的薄膜具有单一的钙钛矿晶格结构,且表面平整致密.对Bi_(3.15)Nd_(0.85)Ti_3O_(12)薄膜的电学性能进行了研究.结果表明,室温下,在测试频率1 MHz时,其介电常数为213,介电损耗为0.085;在测试电压为350 kV/cm,其剩余极化值、矫顽场强分别为39.1 μC/cm~2、160.5 kV/cm;表现出良好的抗疲劳特性和绝缘性能.     

硅硼玻璃相对Bi3.15La0.75Ti3O12铁电薄膜性能的影响

采用加入硅硼玻璃相的溶胶-凝胶(Sol-Gol)技术,以无机物为原料,在低温下成功制备了Pt/Ti/SiO2/Si衬底上Bi3.15La0.75Ti3O12(BLT)铁电薄膜.XRD、AFM分析及电学性能的测i式结果表明,600～650℃退火处理的加入硅硼玻璃相BLT铁电薄膜具有单一的层状钙钛矿结构;薄膜表面平整无裂纹、致密,薄膜为多晶生长;其剩余极化强度(2Pr)为27.09 μC/cm2,矫顽场E约为53.1 kV/cm;室温下,在测试频率为1 MHz,经1.0×1011极化反转后,剩余极化值下降约10%,具有良好的抗疲劳特性;薄膜的漏电流密度低于9×10-10 A/cm2.玻璃相提高了薄膜的致密度和抗疲劳特性,降低了薄膜的漏电流密度,对剩余极化强度影响有限.     

酚磺乙胺对酶法测定肌酐结果的影响

采用加入硅硼玻璃相的溶胶-凝胶(Sol-Gol)技术,以无机物为原料,在低温下成功制备了Pt/Ti/SiO2/Si衬底上Bi3.15La0.75Ti3O12(BLT)铁电薄膜.XRD、AFM分析及电学性能的测i式结果表明,600～650℃退火处理的加入硅硼玻璃相BLT铁电薄膜具有单一的层状钙钛矿结构;薄膜表面平整无裂纹、致密,薄膜为多晶生长;其剩余极化强度(2Pr)为27.09 μC/cm2,矫顽场E约为53.1 kV/cm;室温下,在测试频率为1 MHz,经1.0×1011极化反转后,剩余极化值下降约10%,具有良好的抗疲劳特性;薄膜的漏电流密度低于9×10-10 A/cm2.玻璃相提高了薄膜的致密度和抗疲劳特性,降低了薄膜的漏电流密度,对剩余极化强度影响有限.     

RF溅射法制备PZT铁电薄膜及其表征

采用对靶溅射法在SiO2/Si基板上沉积Pt/Ti底电极,用射频(RF)溅射法在Pt/Ti/SiO2/Si基板上制备了厚度约800 nm的PZT薄膜。XRD分析表明,Ar气氛中沉积,700℃下快速退火(RTA)20 min所得的PZT薄膜具有钙钛矿结构;SEM、AFM分析表明,该条件下所得薄膜的表面由平均粒径约219 nm的晶粒组成,较为均匀、致密。在1 kHz的测试频率下,PZT薄膜的介电常数为327.6,从电滞回线上可以得出,该PZT薄膜的矫顽场强为50 kV/cm,剩余极化强度和自发极化强度分别为10μC/cm2、13μC/cm2。     

LaNiO3/PbZr0.4 Ti0.6 O3/LaNiO3的疲劳特性研究

采用化学溶液法在Si基衬底上制备了PbZr0.4Ti0.6O3/LaNiO3异质结构。X-射线衍射测量结果表明,制备的PbZr0.4Ti0.6O3/LaNiO3异质结构中PbZr0.4Ti0.6O3薄膜呈高度(100)择优取向;原子力显微镜测量表明制备的PbZr0.4Ti0.6O3薄膜的表面平整、均匀、结构致密;RT-66A测量表明,400 kV/cm的外加电场下,LaNiO3/PbZr0.4Ti0.6O3/LaNiO3结构具有优良的铁电性,剩余极化强度为14.6μC/cm2,矫顽电场为41 kV/cm。翻转1×108次极化下降小于10%,显示了很好的疲劳特性。并进一步研究了Pb含量对PbZr0.4Ti0.6O3薄膜的微结构和极化特性的影响。     

快速热处理中退火温度对Sol-gel法制备PZT铁电薄膜性能的影响

利用Sol-Gel法在Pt/TiO2/SiO2/Si基底上用快速热处理(Rapid Thermal Processing,RTP)退火工艺制备出了致密的PZT铁电薄膜,主要研究了在退火时间为500s时退火温度对薄膜的结晶结构、表面形貌和铁电性能的影响。通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)和铁电测试仪对制备的薄膜进行了性能表征。研究结果表明,当退火温度为6000C时,PZT薄膜具有(111)择优取向,表面致密无裂纹,且具有较好的铁电性能(其饱和极化值约为30 C/cm2,剩余极化约为20 C/cm2,矫顽场约为150KV/cm)。在100KV/cm电场下,电流密度J在10-1A/cm2数量级,表明所制的PZT纳米薄膜质量较好,能承受较高的场强以达到饱和极化状态而不被击穿。     

直接感光法制备锆钛酸铅镧薄膜图形及其性能

采用化学修饰溶胶凝胶工艺,以PVP为薄膜开裂抑制剂,以苯酰丙酮为化学修饰剂,利用其与金属盐形成的配位螫合物结构,合成了具有紫外光感应特性的锆钛酸铅镧(Pb0.91La0.09(Zr0.65Ti0.35)O3,PLZT)前驱溶胶;对单次提拉得到的凝胶薄膜进行直接感光法图形制备;通过后续热处理,在Pt/TiO2/SiO2/Si衬底上得到了具有钙钛矿结构的PLZT薄膜图形,其最终热处理后的膜厚约为260nm,剩余极化强度约为6.7μC/cm2,矫顽场强约为77kV/cm,相对介电常数约为356,介电损耗约为0.02,漏电流密度小于10-2μA/cm2,极化疲劳特性可达107以上.     

直接感光法制备锆钛酸铅镧薄膜图形及其性能

采用化学修饰溶胶凝胶工艺,以PVP为薄膜开裂抑制剂,以苯酰丙酮为化学修饰剂,利用其与金属盐形成的配位螫合物结构,合成了具有紫外光感应特性的锆钛酸铅镧(Pb0.91La0.09(Zr0.65Ti0.35)O3,PLZT)前驱溶胶;对单次提拉得到的凝胶薄膜进行直接感光法图形制备;通过后续热处理,在Pt/TiO2/SiO2/Si衬底上得到了具有钙钛矿结构的PLZT薄膜图形,其最终热处理后的膜厚约为260nm,剩余极化强度约为6.7μC/cm2,矫顽场强约为77kV/cm,相对介电常数约为356,介电损耗约为0.02,漏电流密度小于10-2μA/cm2,极化疲劳特性可达107以上.     

采用氧化物复合底电极的BTO薄膜结构和性能

用球磨法制备Bi4Ti3O1(2BTO)靶材。用PLD法在Pt/TiO2/SiO2/Si基片上先分别以三种氧化物SrRuO(3SRO)、LaSrCoO3(LSCO)、LaNiO3(LNO)和Pt生成复合底电极,再在其上生长了外延取向的BTO薄膜。分析了薄膜的结构和性能。结果表明,这种BTO薄膜的c轴取向得到抑制,其极化强度从0.45×10–6C/cm2提高到0.9×10–6C/cm2;矫顽场强从90×103V/cm下降到50×103V/cm。     

TiO_2对BIT薄膜的微观结构和铁电性能的影响

用sol-gel法先后分别在ITO/石英衬底上制备了Ti O2缓冲层和Bi4Ti3O12铁电薄膜层。研究了Ti O2缓冲层对BIT铁电薄膜结构和铁电性能的影响。结果表明:Ti O2层加入后BIT薄膜呈现出(117)择优取向,降低了BIT薄膜成核所需要的能量,促进了晶粒的生长,使得薄膜更加致密。当ITO基底与BIT薄膜之间加入40nm厚的Ti O2层,能够得到26.99μC/cm2的剩余极化值。     

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.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.