钛酸钡基厚薄膜PTCR的研究

介绍了钛酸钡基厚、薄膜PTCR的制备方法与研究进展。射频磁控溅射和溶胶-凝胶成膜技术是制备陶瓷PTCR薄膜的较理想的方法。陶瓷PTCR厚膜技术由于具有成本低和较好的市场前景受到人们的高度重视。目前钛酸钡基PTCR厚、薄膜技术的研究已经取得了较大的进步和发展。PTCR膜材正向着低室温电阻、高升阻比和集成化的方向发展。     

超细钛酸钡粉体湿化学合成技术

近十年来，钛酸钡粉体的合成技术发展十分迅速。其中，超细钛酸钡粉体的湿化学合成技术倍受关注，主要包括溶胶-凝胶、溶胶-沉淀、燃烧合成、化学共沉淀和水热合成等多种方法。简要综述了这5种主要的湿化学合成工艺，并重点分析了溶胶-凝胶法等制备钛酸钡粉体过程中各种因素对粉体的粒径和形态的影响。     

纳米氧化钨薄膜的制备方法及其性质研究

综述了纳米氧化钨薄膜的各种制备方法：溶胶-凝胶法、溅射法、蒸发法、化学气相沉积法、阳极氧化法等，并比较了其优缺点；介绍了氧化钨薄膜的掺杂研究；对纳米氧化钨薄膜的电致变色、气敏特性等性质研究现状作了简要概述，提出了纳米氧化钨薄膜的发展前景。     

大面积FTO透明导电薄膜制备技术研究进展

掺氟氧化锡透明导电(FTO)薄膜由于性价比优势,已成为薄膜太阳电池的重要原材料,但其导电性能不佳导致商用大面积薄膜太阳电池光电转换效率只有实验室小面积薄膜太阳电池效率的40%~60%,提高大面积FTO薄膜的导电性能和降低生产成本成为其广泛应用的关键。介绍了化学气相沉积法、喷雾热分解法、磁控溅射法和溶胶-凝胶法制备FTO薄膜的工艺和技术进展。对改进大面积FTO薄膜导电性能的新途径和国内外研究进展做了综述。建议重点研究锑磷掺杂FTO薄膜制备技术和重点研究纳米银复合FTO薄膜制备技术,以克服FTO薄膜电阻较大的缺陷,同时保持导电薄膜良好透光性能。     

溶胶－凝胶法制备掺杂二氧化钛薄膜及其光电性能研究

溶胶－凝胶法制备掺杂二氧化钛薄膜及其光电性能研究徐灵戈，黎甜楷（中国科学院感光化学研究所，北京１００１０１）王淑琴，徐维并（中国科学院生态环境研究中心，北京１０００８５）关键词溶胶－凝胶法，掺杂二氧化钛薄膜，光电性能，红外光谱运用溶胶－凝胶法制备玻璃...     

钛酸钡掺杂镧电子陶瓷制备的研究

在钛酸钡陶瓷中掺入稀土多酸微量元素(0.1%～0.3%),会使钛酸钡陶瓷的电阻率降低,由绝缘变为半导体。那么减小杂量掺杂是否对钛酸钡陶瓷有同样的作用呢?为此在实验中采用溶胶-凝胶法制备掺杂稀土元素镧的钛酸钡纳米晶,考察了掺杂量分别为0.01%～0.05%和0.1%～0.5%的钛酸钡纳米晶的部分特征,以及杂质的掺入对钛酸钡粒径、煅烧温度和晶胞参数等方面的影响。     

TiO_2薄膜超亲水性研究进展

简述了TiO2薄膜材料的超亲水性机理,概括了制备TiO2薄膜的基本方法有:静电自组装技术、微等离子体氧化法、液相沉积法、溶胶-凝胶法、化学气相沉积法、磁控溅射法等;并简要介绍了TiO2薄膜超亲水性材料在自清洁建材、防雾涂层、杀菌消毒等方面的应用现状与发展前景,并展望了今后的研究工作。     

纳米TiO2薄膜制备方法的研究进展

纳米二氧化钛以其优异的化学、物理性能受到关注。薄膜是纳米二氧化钛的重要形式,制备纳米二氧化钛薄膜具有重要意义和很好的应用前景。依据制备工艺中温度的要求,对制备纳米二氧化钛薄膜的方法进行了概述,高温制备的工艺主要有溶胶-凝胶法、水热法、气相沉积法,低温制备工艺主要有电泳沉积法、紫外光照射法、电化学制备法、模板自组装制备法。     

Zr掺杂对BaTiO3陶瓷微观形貌及性能的影响

采用溶胶-凝胶法制备了锆掺杂的钛酸钡陶瓷,通过XRD、SEM等分析检测手段对所得锆钛酸钡陶瓷样品进行了表征。系统地研究了Zr掺杂对BaTiO_3基陶瓷相组成、微观形貌和介电性能的影响。结果表明,锆钛酸钡陶瓷样品均为单一的立方相钙钛矿结构,晶粒大小均匀,随着Zr掺杂量的增加,陶瓷晶粒尺寸先增大后减小,孔隙逐渐增多,介电常数先增大后减小,介电损耗先减小后增大。     

纳米TiO2薄膜制备方法的研究进展

纳米二氧化钛以其优异的化学、物理性能受到关注。薄膜是纳米二氧化钛的重要形式,制备纳米二氧化钛薄膜具有重要意义和很好的应用前景。依据制备工艺中温度的要求,对制备纳米二氧化钛薄膜的方法进行了概述,高温制备的工艺主要有溶胶-凝胶法、水热法、气相沉积法,低温制备工艺主要有电泳沉积法、紫外光照射法、电化学制备法、模板自组装制备法。     

Cu_3N薄膜制备及其性能研究

Cu3N薄膜的晶面取向、沉积速率、电学特性等性质除与制备方法有关外,还和制备工艺参数有很大关系。溅射法制备Cu3N薄膜工艺参数主要有,混合气体(N2+Ar)中氮气分压比r、基底温度T(℃)、溅射功率P(W)。为了研究Cu3N薄膜的性能与其制备工艺参数之间关系,本文采用反应射频磁控溅射法,在玻璃基底上成功制备了Cu3N薄膜,并研究了工艺参数对其晶面取向、膜厚、电学性能、沉积速率的影响。     

Niobium-based catalysts prepared by reactive radio-frequency magnetron sputtering and arc plasma methods as non-noble metal cathode catalysts for polymer electrolyte fuel cells

Two vacuum methods, reactive radio-frequency (RF) magnetron sputtering and arc plasma deposition, were used to prepare niobium-based catalysts for an oxygen reduction reaction (ORR) as non-noble metal cathodes for polymer electrode fuel cells (PEFCs). Thin films with various N and O contents, denoted as NbO_x and Nb-O-N, were prepared on glassy carbon plates by RF magnetron sputtering with controlled partial pressures of oxygen and nitrogen. Electrochemical measurements indicated that the introduction of the nitrogen species into the thin film resulted in improved ORR activity compared to the oxide-only film. Using an arc plasma method, niobium was deposited on highly oriented pyrolytic graphite (HOPG) substrates, and the sub-nanoscale surface morphology of the deposited particles was investigated using scanning tunneling microscopy (STM). To prepare practical cathode catalysts, niobium was deposited on carbon black (CB) powders by arc plasma method. STM and transmission electron microscopy observations of samples on HOPG and CB indicated that the prepared catalysts were highly dispersed at the atomic level. The onset potential of oxygen reduction on Nb-O-N/CB was 0.86 V vs. a reversible hydrogen electrode, and the apparent current density was drastically improved by the introduction of nitrogen.     

Resistive switching characteristics of sputtered AlN thin films

AlN thin films were deposited on Pt/Ti/SiO₂/Si substrates using a radio-frequency magnetron sputtering technique. The effect on the switch current–voltage characteristics of four different materials in the electrode fabricated on top of the AlN film was investigated. The deposition time and nitrogen content in the sputtering atmosphere were changed to adjust the thickness and composition of the AlN thin films, respectively. The influence of film thickness and content on the resistive switching behavior was discussed. The possible mechanism of resistive switching was examined via analyses of the electrical resistive switching characteristics, forming voltage, and on/off current ratio.     

Evaluation of Lead Zirconate–Titanate Ceramic Target for Sputter Deposition of Films for Use in Ferroelectric Capacitors

A high-density 3 in. diameter (Pb,La)(Zr,Ti)O3 [PLZT] ceramic target containing 20% excess PbO was sputtered by radio-frequency magnetron sputtering to deposit films containing excess Pb and evaluated with respect to target stability for use in the mass production of ferroelectric memories on Si wafers. The results indicated that PLZT film deposition rate increased with power but the excess PbO content correspondingly decreased. The Pb loss in the films was attributed to secondary preferential sputtering of film substrate in the plasma. Regardless of this difference, excess PbO containing 12 in. diameter PLZT ceramic targets were evaluated in a commercial sputtering system over a period of 7 months and the film Pb content was stable within ±1%.     

Ultra Thin Organic and Polymer Films

Abstract

Preparation of ultra thin organic and polymer films could be divided into two methods. One is the wet process such as Langmuir-Blodgett (LB), spreading, dipping and casting methods. The other is dry processing, such as vapor deposition, sputtering, chemical vapor deposition, plasma polymerization and vapor deposition polymerization methods. Of these methods, the LB method has been attractive for the last decade to prepare a monolayer film, however, the vapor deposition method has also attracted attention for the preparation of well organized ultra thin films. It is important to investigate a molecular assembly in terms of the extent of aggregation, the crystalline regularity and their orientation in the thin film, since they are closely related to the physical, electrical and functional properties. This review focuses on an evaluation of the structure, molecular assembly and orientation in the thin films prepared by the LB and vapor deposition methods.     

Yttria-stabilized zirconia thin films with restrained columnar grains for oxygen ion conducting electrolytes

Yttria-stabilized zirconia thin films with restrained columnar grains were deposited by modifying the DC reactive magnetron sputtering conditions. Usually, films fabricated by physical vapor deposition (PVD) method generate columnar grain structures due to its deposition characteristics. The grain boundaries between these columnar grains can be considered as structural defects and causes serious issues for the application of thin film electrolyte of energy conversion systems. By modifying the background pressure and deposition temperature of the reactive sputtering method, YSZ thin films having restrained columnar grains were successfully fabricated. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations were conducted to analyze the surface morphologies, grain structures, and nano-defects in the interior of the YSZ thin film. Through the analysis, restrained columnar microstructures of the YSZ films were deposited as dense and homogeneous. The film also showed higher ionic conductivity compared to that of the columnar structure due to the reduced ion transport blocking effect. Moreover, the fuel cell fabricated with the YSZ electrolyte having restrained columnar grains showed superior performance in terms of the peak power density than the fuel cell with columnar grain electrolyte structure.     

碳化钨纳米晶薄膜电极在对硝基苯酚电化学还原中的催化性能

采用磁控溅射物理气相沉积和等离子体增强化学气相沉积技术,在金属镍基体上制备具有纳米晶结构的碳化钨薄膜;采用循环伏安、准稳态极化和恒电位阶跃等电化学方法研究了对硝基苯酚(PNP)在碳化钨纳米晶薄膜电极上电化学还原的特性和机理.研究表明,采用磁控溅射物理气相沉积技术制备得到的薄膜是由直径为20nm的WC1-X构成,在这种薄膜电极上,PNP电化学还原在电位为(0.95V(Vs. SCE)时,出现一个电流密度为6.0mA(cm(2还原峰,还原反应的表观活化能为12.0kJ(mol(1;而采用等离子体增强化学气相沉积技术制备得到的薄膜是由直径为35nm的纯相WC构成,PNP在该薄膜电极上电化学还原峰电位为(1.05 V(Vs. SCE),还原电流达10.0 mA(cm(2,表观活化能为10.9 kJ(mol(1. PNP在这两种碳化钨薄膜电极上都经过两步不可逆的电化学反应还原成对氨基苯酚,控制步骤为电极反应的电荷传递过程.     

Increase of the Surface Mobility of Carbon Molecular Crystals (CMCs) Using the PECVD Technique

Large-area boron doped multi-layer carbon is synthesized by the plasma enhanced chemical vapour deposition (PECVD) using boron oxide powder and ethanol vapor. We have reviewed the carbon molecular crystals preparation by the PECVD method. The three main synthesis methods of carbon nanocrystals (CNCs) are the arc discharge, the laser ablation and the chemical vapour deposition with a special regard to the later one. By two different methods, ZnO layers were coated on the tubes. RF sputtering was one of the ways to directly deposit ZnO thin layer on the MWCNCs. On the other hand, we used thermally physical vapour deposition for making thin Zn film to oxidize it later. Scanning electron microscopy and also Raman spectroscopy measurements of the prepared samples confirmed the presence of ZnO nanolayers on the CNC bodies.     

Growth and crystallographic feature-dependent characterization of spinel zinc ferrite thin films by RF sputtering

ZnFe₂O₄ (ZFO) thin films exhibiting varying crystallographic features ((222)-epitaxially, (400)-epitaxially, and randomly oriented films) were grown on various substrates by radio-frequency magnetron sputtering. The type of substrate used profoundly affected the surface topography of the resulting ZFO films. The surface of the ZFO (222) epilayer was dense and exhibited small rectangular surface grains; however, the ZFO (400) epilayer exhibited small grooves. The surface of the randomly oriented ZFO thin film exhibited distinct three-dimensional island-like grains that demonstrated considerable surface roughness. Magnetization-temperature curves revealed that the ZFO thin films exhibited a spin-glass transition temperature of approximately 40 K. The crystallographic orientation of the ZFO thin films strongly affected magnetic anisotropy. The ZFO (222) epitaxy exhibited the strongest magnetic anisotropy, whereas the randomly oriented ZFO thin film exhibited no clear magnetic anisotropy.