La2O3掺杂的SrTiO3陶瓷的介电性质

SrTiO_3陶瓷是一种具有多功能特性的介质材料。用La_2O_3掺杂改性的SrTiO_3陶瓷,可以提高其介电常数和降低介质损耗,对其介电温度特性和介电频率特性也有明显的改善.本文主要报道 La_2O_3对SrTiO_3陶瓷介电性质的影响。     

混合型高电压超级电容器的研究

通过优化组合电解电容器的阳极和电化学电容器的阴极,以Ta/Ta2O5为阳极,活性炭为阴极,研制了一种单元工作电压为100V的混合型超级电容器。该电容器与超级电容器相比较,工作电压得到了提高。测试表明其具有高储能密度和快速充放电的能力,频谱阻抗(EIS)分析显示其具有优良的阻抗特性和频率特性。     

Ta2O5薄膜的离子敏感特性

用磁控溅射法制备了Ｔａ２Ｏ５薄膜，再用Ｃ－Ｖ法和ＪＦＥＴ外接薄膜电极法研究其稳定性和离子响应灵敏度。实验发现，在纯氧中沉积的厚２００ｎｍＴ２Ｏ５薄膜有较高的离子响应灵敏度，实验发现，在纯氧中沉积的厚２００ｎｍＴ２Ｏ５薄膜有较高的离子响应灵敏度和良好的稳定性。     

Ta2O5薄膜的结构和电学性能研究

采用紫外光诱导热丝CVD沉积技术制备Ta2O5薄膜和Al/Ta2O2/SiMOS电容。利用XRD，AFM测试分析方法研究了紫外光源功率对Ta2O5薄膜结构的影响；通过C-V和，I-V测试对Ta2O5薄膜的介电常数，击穿场强和漏电流等电学性能进行了研究，结果表明：紫外光源的功率越大，Ta2O5薄膜的结晶性越好，介电常数越大，最大值为29，但紫外光功率对击穿场强和漏电流没有明显改善。     

一种新型湿化学方法合成Ba(Mg1/3Ta2/3)O3纳米粉末的研究

介绍了一种工艺简便且成本较低的Ba(Mg1/3Ta2/3)O3(BMT)纳米粉末的湿化学制备方法.实验过程以Ta2O5作为起始物,通过热碱反应与钽离子浓度控制法合成Ta2O5@nH2O胶体,然后与Ba、Mg醋酸盐按化学计量比混合,经热处理制得BMT纳米粉末.实验结果表明该方法制备BMT粉体所需的合成温度仅为800℃,比传统固相反应法合成温度降低400℃左右,平均粒径仅为70nm.此外所制得的纳米陶瓷材料具有较佳的低温烧结性能和微波介电特性,比目前报道的醇盐系湿化学制备技术更具有实用性.     

Ti6Al4V钛合金表面Ta2O5/Ta2O5-Ti/Ti多涂层的制备与性能研究

采用磁控溅射技术在Ti6Al4V钛合金表面制备了Ta_2O_5/Ta_2O_5-Ti/Ti多层涂层;利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)和X射线光电子能谱仪 (XPS),分析了涂层的微观结构、物性组成和化学价态;通过划痕仪、纳米压痕仪、摩擦磨损试验机和电化学工作站,检测了涂层的结合强度、力学性能、摩擦系数和耐腐蚀性。研究结果表明,Ta_2O_5/Ta_2O_5-Ti/Ti多层涂层表面由峰型颗粒组成,粒径大小均匀,涂层结构致密。与Ti6Al4V相比,Ta_2O_5/Ta_2O_5-Ti/Ti多层涂层试样具有较小的摩擦系数,较高的腐蚀电位和较小的腐蚀电流密度,表现出良好的耐磨和耐腐蚀性能,能对Ti6Al4V合金植入材料起到较好的保护作用。     

衬底负偏压对溅射Ta2O5薄膜晶化温度及介电性能的影响

采用磁控溅射法，在衬底温度为620℃时，通过引入合适的衬底负偏压(100—200V)，获得了结晶良好的Ta2O5薄膜．衬底负偏压增强了正离子对衬底表面的轰击作用，加速了其在衬底表面的松弛扩散效应，从而降低了Ta2O5薄膜的晶化温度，改善了其结晶性．同时，G—V测试结果表明：衬底负偏压进一步改善了Ta2O5薄膜的介电性能．     

一种新型湿化学方法合成Ba(Mg1/3Ta2/3)O3纳米粉末的研究

介绍了一种工艺简便且成本较低的Ｂａ（Ｍｇ１／３Ｔａ２／３）Ｏ３（ＢＭＴ）纳米粉末的湿化学制 备方法．实验过程以Ｔａ２Ｏ５作为起始物，通过热碱反应与钽离子浓度控制法合成Ｔａ２Ｏ５·ｎＨ２Ｏ 胶体，然后与Ｂａ、Ｍｇ醋酸盐按化学计量比混合，经热处理制得ＢＭＴ纳米粉末．实验结果表 明该方法制备ＢＭＴ粉体所需的合成温度仅为８００℃；比传统固相反应法合成温度降低４００℃ 左右，平均粒径仅为７０ｎｍ此外所制得的纳米陶瓷材料具有较佳的低温烧结性能和微波介电 特性，比目前报道的醇盐系湿化学制备技术更具有实用性．     

氧化钽薄膜表面形貌和光学性能的研究

本文采用电子束蒸发配以Kaufman离子源产生的氧离子辅助沉积了Ta2O5薄膜,用原子力显微镜（AFM）表征了薄膜的表面形貌、表面粗糙度,探讨了Ta2O5薄膜在此工艺下的表面质量.用分光光度计测试了不同厚度下薄膜的透射率,计算出了其折射率.实验及分析结果表明：所制备的Ta2O5薄膜表面平整度高,是弱吸收薄膜,随薄膜厚度的增加短波截止波长向长波方向略有漂移;折射率随膜厚的变化不大,此制备工艺的可重复性强,制备薄膜性能稳定;薄膜表面粗糙度随膜厚的增加而增加,但是增加不大,所制备Ta2O5薄膜是理想光学薄膜;离子束的加入,使得薄膜表明形貌变化更加复杂,打破了热蒸发制备薄膜的柱状生长模式.     

退火温度对Ta2O5薄膜光学和表面特性的影响

针对退火温度影响Ta₂O₅薄膜的光学和表面特性的问题，采用电子束蒸发技术在石英基底上制备了该薄膜，并将薄膜样品分别在200℃、400℃和600℃下进行退火。利用光谱仪测试了薄膜的透射率并反演计算得到薄膜的折射率和消光系数的变化规律，采用X射线衍射仪和原子力显微镜表征了薄膜的表面性能。研究表明，薄膜透射率曲线的峰值随退火温度升高而显著提升。随着退火温度升高，薄膜的折射率和消光系数均逐渐变大，表面粗糙度呈现下降的趋势，表面变得致密。退火前后薄膜均为非晶态。该研究为进一步提高Ta₂O₅薄膜的性能提供了试验数据。     

Effects of insulating layer on the performance of thin film electroluminescent devices

Thin film electroluminescent devices were fabricated with active layer of ZnS:Mn and different insulators viz Sm₂O₃, Eu₂O₃, Na₃A1F₆, MgF₂, CeO₂ and SiO in MIS and MISIM structure. The threshold voltage for light emission in AC thin film electroluminescent devices of MIS and MISIM structures is found to depend on the dielectric properties of insulating materials. The observed threshold voltage for these devices and its variations for devices with different insulators are explained using the equivalent circuit for the device and the dielectric properties of the insulting material used for the preparation of device. Variation of threshold voltage with operating time is also studied for some of the devices.     

无机薄膜电致发光器件中绝缘层材料的研究

薄膜电致发光（TFEL）技术将戍为平板显示技术的潮流和主体。简要介绍了平板显示技术的发展，同时对无机薄膜电致发光器件中绝缘层材料的选择进行了探讨。     

不锈钢基Al2O3/SiC双层薄膜的制备和性能

用磁控溅射法在奥氏体不锈钢上分别制备了SiC单层膜和Al2O3/SiC双层膜,研究了溅射气压,溅 射功率以及退火温度对性能的影响.对比了二者的结构、硬度以及耐腐蚀性.结果表明,Al2O3缓冲层降低了SiC薄膜与奥氏体不锈钢基底的热失配和晶格失配,减少了因其而产生的缺陷,从而改善了奥氏体不锈钢上SiC薄膜的结晶质量.     

Oxide phosphor and dielectric thin films for electroluminescent devices

Since its inception in the early 1990s, the field of high brightness, high stability oxide phosphor electroluminescence (OPEL) continues to develop with efforts now underway in several groups around the world. Green-emitting phosphors Zn₂SiO₄:Mn, Zn₂Si_1−xGe_xO₄:Mn and ZnGa₂O₄:Mn achieve efficiencies of 0.5-2.5 lm/W. Lifetimes of 50 000 h in air are achieved, even without control of humidity. Red emission from Ga₂O₃:Eu and MgGa₂O₄:Eu has also been realized, with efficiencies approaching 1 lm/W. Recently, higher efficiencies of up to 10 lm/W have been reported in yellow emitting Y₂O₃:Mn and (Y₂O₃)_x(GeO₂)_y:Mn. Commercialization of OPEL for flat panel displays and lamps on glass substrates requires the development of phosphors that may be deposited at temperatures of 700 °C or lower. Several approaches are described here. A vacancy mechanism is shown to control the enhancement of crystallization in ZnGa₂O₄ by the introduction of CdO to form compounds of Zn_1−xCd_xGa₂O₄:Mn. Here, sputtering targets and as-deposited thin films contain Cd atoms, but the annealed thin films undergo complete loss of Cd as they crystallize. It is also shown that a flux such as LiF maybe added to Zn₂SiO₄:Mn to lower crystallization temperature. Here it is likely that point defects Li_Zn and F_o permit charge compensation while lowering the crystallization temperature. High breakdown strength, high dielectric constant and transparent dielectric layers have been developed to permit long life OPEL on Corning 1737 glass substrates. Whereas it is commonly reported that SrTiO₃ and other perovskite titanate and zirconate dielectrics are not self-healing, it has been shown that a SrTiO₃ dielectric of thickness 2 μm prepared using three sub-layers does achieve self-healing. In conjunction with a Zn₂Si_0.5Ge_0.5O₄:Mn phosphor, excellent steep-threshold electroluminescence (EL) behaviour is observed with L50, the brightness 50 V over threshold at 60 Hz of over 300 cd/m². Finally, results for a new phosphor system Ga_2−xIn_xO₃:Eu on glass substrates are reported, in which the electric field for EL is reduced.     

磁控反应溅射制备的Ta2O5薄膜的光学与介电性能

采用直流磁控反应溅射技术，在不同的Ar/O2比条件下制备了系列Ta2O5薄膜样品，采用紫外．可见光透射光谱和椭偏光谱测试分析技术，研究了Ta2O5薄膜在可见光范围内的透射率、折射率和消光系数；同时还采用HP 4192A阻抗分析仪测试分析了样品在500Hz～13MHz频段的介电谱，结果表明在300～700nm的可见光波长范围内，氧化钽薄膜的消光系数k→0，折射率＞2．0，透射率大约80％。500Hz下的低频介电常数5的典型值为20.1。损耗角正切tgδ为19.9。     

V2O5薄膜用作SO2气敏传感器

在O2/Ar气氛中，用射频磁控溅射法在常温下溅射V2O5粉末靶得到氧化钒薄膜。在350℃热处理后，经XRD分析，薄膜的主要成分为V2O5。在不同温度下对V2O5薄膜作了对“空气和SO2”的混合气氛的敏感特性测试分析，发现在300～390℃范围内，薄膜对SO2气体灵敏随温度的升高而增大，在超过390℃后，灵敏度随温度升高而降低。在SO2气体去除后，薄膜的电阻值能恢复到初始状态，气敏过程可反复进行。文章对V2O3薄膜的气敏机理作了定性描述。     

Molecular layer deposition of ZrO2-based organic-inorganic nanohybrid thin films for organic thin film transistors

Molecular layer deposition (MLD) technique can be used for preparation of various organic-inorganic nanohybrid superlattices at a gas-phase. The MLD method is a self-controlled layer-by-layer growth process under vacuum conditions, and is perfectly compatible with the atomic layer deposition (ALD) method. In this paper, we fabricated a new type organic-inorganic nanohybrid thin film using MLD method combined with ALD. A self-assembled organic layer (SAOL) was formed at 170 °C using MLD with repeated sequential adsorptions of CC terminated alkylsilane and zirconium hydroxyl with ozone activation. A ZrO₂ inorganic nanolayer was deposited at the same temperature using ALD with alternating surface-saturating reactions of Zr(OC(CH₃)₃)₄ and H₂O. The prepared SAOL-ZrO₂ organic-inorganic nanohybrid films exhibited good mechanical stability, excellent insulating properties, and relatively high dielectric constant k (~ 16). They were then used as a 23 nm-thick dielectric for low voltage pentacene-based thin film transistors, which showed a maximum field effect mobility of 0.63 cm²/V s, operating at − 1 V with an on/off current ratio of ~ 10³.     

新型SnO2/WO3双层薄膜NO2敏感性能研究

采用射频磁控反应溅射锡(Sn)靶和钨(W)靶的方法制备了SnO2/WO3双层薄膜材料,通过XRD和XPS实验研究了双层薄膜的物相结构和组份,结果表明,SnO2/WO3双层薄膜经过热处理后形成了SnWO4化合物.在此基础之上,制作了相应的NO2气体敏感薄膜传感器,研究了双层薄膜传感器的制备工艺参数及工作条件对传感器性能的影响,研究了传感器的敏感特性,包括灵敏度、选择性、响应恢复等特性.结果表明,传感器对NO2气体有较好的敏感性,对其他干扰气体不敏感.     

多孔硅表面氧化钒热敏电阻薄膜的阻温特性

用电化学腐蚀法制备了具有不同导热系数的多孔硅样品(孔隙率为80％±2、厚度为110μm时,导热系数可降低至0．20 W／m·K),并在其表面沉积了氧化钒热敏薄膜,研究了多孔硅样品的热绝缘性能对氧化钒热敏薄膜阻温特性的影响．结果表明:多孔硅良好的热绝缘性使在其表面制备的氧化钒热敏薄膜电阻的灵敏度远高于在硅基底上制备的热敏电阻的(多孔硅和硅片上的氧化钒薄膜电阻随功率变化斜率分别为120 kΩ／μW和2．1 kΩ／μW),且热敏电阻的灵敏度随着多孔硅孔隙率和厚度的增大而升高．     

Improved crystallization characteristics of ZnO thin film grown onto a-C:H film used as a buffer layer

We employed a-C:H buffer layer to improve the crystalline property of ZnO thin film for the membrane film bulk acoustic resonator (FBAR). The a-C:H film as a buffer layer is prepared by applying dc bias of 200 V and also this sample showed a smoother surface roughness, higher hardness and Young's modulus when compared to the other samples. In addition, the FWHM value was improved from 7.5 to 4.3° on a-C:H film. The fabricated FBAR device showed the resistivity of 0.73 × 10⁸ Ω when compared with no buffer layer and the frequency characteristics of the FBAR were finally confirmed to be 1.15 GHz and 21.24 dB, respectively.