Sapphire orientation dependence of the microstructure of ZnO thin film during annealing

The sapphire orientation dependence of the microstructure of ZnO thin films has been studied in real-time synchrotron X-ray scattering experiments. The ZnO films with a 2400-Å-thick were grown on sapphire (001) and sapphire (110) substrates at room temperature by radio frequency magnetron sputtering. The as-deposited ZnO film on sapphire (001) has the only (002) crystal grains, while that on sapphire (110) has not only (002) crystal grains but (100) and (101) additional grains. The ZnO films were changed into fully epitaxial ZnO (002) grains both on sapphire (001) and sapphire (110) substrates with increasing the annealing temperature to 600^°C. The epitaxial relationships of the ZnO grains were summarized as ZnO (00l)[100]//sapphire (00l)[110] and ZnO (00l)[110]//sapphire (110)[001].     

重力沉降法结合共烧结法制备YSZ薄膜

采用重力沉降法和共烧结法相结合,在NiO-YSZ(氧化钇稳定氧化锆)阳极基底上制备YSZ固体电解质薄膜,在1 400℃下共烧结后,得到厚度为20 μm的YSZ薄膜.利用XRD和SEM对薄膜的相结构、形貌等进行表征.以La0.4Sr0.6Co0.2Fe0.8O3(LSCF)为阴极制成单电池,对其性能及阻抗谱进行测试.在620℃时,得到单电池的最大开路电压为0.98 V;850℃时的电流密度接近1 A/cm2,最大功率密度为180 mW/cm2.     

智能卡及其应用的薄膜锂电池

近年来智能卡的迅速发展对内置电源提出了需求。全固态薄膜锂蓄电池以及聚合物薄膜锂蓄电池已经成功地应用于智能卡当中。介绍了全固态薄膜锂蓄电池、聚合物薄膜锂蓄电池的制备工艺,比较了VartaBattery,CymbetCorporation,InfinitePowerSolutions,SolicoreInc.四家公司的商业化薄膜锂一次电池和锂蓄电池的制备以及相关特性。     

Effect of vanadium doping on ferroelectric and electrical properties of Bi3.25La0.75Ti3O12 thin film

Bi_3.25La_0.75Ti₃O₁₂ (BLT) and V-doped BLT (BLTV) thin films were prepared on Pt/Ti/SiO₂/Si substrates by a pulsed laser deposition method. The effects of V doping on ferroelectric and electrical properties were investigated by polarization-electric field hysteresis loops and leakage current-voltage measurements. BLTV single phases were confirmed by X-ray diffraction. Remnant polarization was increased and the leakage current density was decreased by V doping. The leakage current density of BLT thin films suddenly increased at 100 kV/cm while that of BLTV thin films increased at the higher electric field of 160 kV/cm. The power law relationship J α Eⁿ of current density vs. applied electric field is estimated to be J αE^2.0 for BLT and J αE^1.0 for BLTV thin films. The leakage current of the BLT/Pt junction can be explained by space-charge-limited current. However, that of the BLTV/Pt junction was characterized by the Schottky emission behavior.     

Chemically derived seeding layer for {100}-textured PZT thin films

PZT thin films are used extensively in micro electromechanical systems (MEMS) due to its high piezoelectric coefficients. The electromechanical responses can be optimized by using textured films where the transverse coefficient e_31,f is of particular importance for MEMS structures such as cantilevers, bridges and membranes. It has been shown that {100}-textured PZT of morphotropic composition fabricated by chemical solution deposition (CSD) provides the highest transverse coefficient [1]. This specific texture can be obtained using a seeding layer of sputter deposited PbTiO₃ [2]. However, in a CSD process it is advantageous to also be able to produce the seed layer by chemical methods. The piezoelectric and dielectric properties of 2 μm PZT film seeded by CSD PbTiO₃ measured by a new 4-point bending setup are presented.     

全固态薄膜锂蓄电池研究进展

全固态薄膜锂蓄电池是目前国内外电池研究的新热点,其在未来微电子器件中具有广泛的应用前景.综述了全固态薄膜锂蓄电池国内外研究状况,介绍了全固态薄膜锂蓄电池的结构、工作原理及制备方法,并对全固态薄膜锂蓄电池的正负极膜及电解质膜研究情况作了详细的阐述.     

Micro-structure and ferroelectric properties of BiFeO3 thin films formed on Pt-coated r-plane sapphire substrates

Magnetoelectric BiFeO₃ (BFO) materials exhibit ferroelectric and ferromagnetic properties simultaneously, therefore they have a potential to be applied in magnetic as well as ferroelectric devices. BFO thin films were formed by depositing sol-gel solutions on Pt-coated r-plane sapphire dielectric substrates. We did not observe any secondary phase such as Bi₂Fe₄O₉ on the r-plane sapphire substrates, which is generally observed on Si substrates. We observed small ferroelectric grains of about 0.1 μm on Pt/sapphire structures. The leakage current density in BFO films was found to be decreased dramatically after optimizing process conditions of stoichiometric BFO chemical solution. The leakage current densities were in the range of 10^{− 7} A/cm² at room temperature and 10^{− 9} A/cm² at 80 K under 0.4 MV/cm applied electric field. The main reason for low leakage current is considered to be reduction of oxygen vacancies due to the presence of exclusive Fe^{3 +} valance state in the films. An applied electric field higher than 0.5 MV/cm was required to pole the BFO films, which made it difficult to obtain the saturated polarization at room temperature. We could measure the saturated remanent polarization in the BFO films at 80 K and the obtained remanent polarization was 100 μC/cm².     

锂磷氧氮(LiPON)薄膜的制备及应用进展

介绍了锂磷氧氮(LiPON)薄膜的结构与特性,综述了LiPON薄膜的制备方法以及应用情况,并就LiPON薄膜制备中出现的困难和以后的研究方向做了简单的评述.     

Selective growth of ZnO nanorods by patterning of sol-gel-derived thin film

An effective method of fabricating micro and sub micro patterned zinc oxide nanorods without a transient metal catalytic assistants via hydrothermal synthesis using micro molding technique was presented. Micro molding of sol-gel-derived precursor layer was clearly accomplised by conformal contact of elastomeric molds with various kinds of patterns. The selective growth of the nanorods over a large area of the pre-patterned seed layer was observed with a pattern feasibility of 250 nm. The orientation of the nanorods was normal to the seed layer while characteristic sizes of the rod didn’t show any dependence on the diameter of the seed particles. Presented synthetic process can provide simpler way of fabricating an array of semiconductor one-dimensional nanostructures.     

薄膜锂离子电池活化过程研究

设计并制备了厚度仅为0.7 mm,且具有较好电化学性能的薄膜锂离子电池.随着正极片辊压率的增加,电池难以完全活化,同时高倍率放电特性变差.讨论了电解液量、陈化时间及化成工艺等对电池活化过程的影响.     

集成电路开关电源及其高频薄膜磁技术的发展

随着数码相机、手机等便携式电子设备的广泛应用,高功率密度的集成电路小功率开关电源,即单个集成芯片的开关变换器系统的发展,已经越来越成为电力电子领域研究的热点.本文综述了该领域发展现状、主要面临的技术问题及其关键的高频薄膜磁技术发展,阐述了发展方向和可能的方案.     

基于AZO/Ag/AZO透明导电薄膜的染料敏化太阳电池研究

采用化学气相沉积和直流溅射沉积方法成功制备了与基体附着力高的不同Pt厚度的Pt/碳纳米管(CNT)膜层。通过扫描电子显微镜(SEM)和能谱分析(EDS)分别对薄膜厚度和表面形貌以及膜层中Pt的含量进行了研究;通过电化学阻抗谱和循环伏安曲线分别对Pt和Pt/CNT对电极的光电催化性进行了研究。结果表明:CNT与基体具有良好的接触性,并且随Pt沉积时间的增加,Pt在CNT薄膜中的含量增加,染料敏化太阳电池(DSSC)的光电转化效率随Pt厚度的增加而增加;与单纯的Pt对电极相比,Pt/CNT对电极具有更高的活性比表面,更低的电子迁移电阻以及更高的还原电流密度;以Pt(80 nm)/CNT为对电极的DSSC具有最高的光电转化效率8.54%;另外,与Pt(80 nm)对电极相比,以Pt(40 nm)/CNT为对电极制备的DSSC具有更高的光电转化效率,因此,该新型对电极结构可大大节省贵金属Pt的用量,在DSSC的应用中具有很大的潜力。     

Tailoring the structural and optical properties of RF magnetron sputtered ZnO/graphene thin films by annealing temperature

Abstract

ZnO and ZnO/Graphene thin films were deposited on Cu substrate using a low pressure chemical vapor deposition (LPCVD) and the magnetron sputtering method. The impacts of graphene layer growth and annealing temperature on the optical properties ZnO and ZnO/Graphene thin films were investigated by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscope (SEM), X-ray photoelectron spectroscopic (XPS), and photoluminescence (PL) measurements respectively. XRD and SEM results reveal that all the thin films preferred the crystalline [001] orientation along the c-axis direction, which were vertical grown on substrate surface. By comparing the results and analysis of their structure, morphology, chemical bonding and optical property, it is proved that using Graphene as a buffer layer can improve the crystal quality of ZnO thin films. For the annealed ZnO/graphene nanostructures, the area ratio of UV and visible emission region of ZnO/graphene thin films increase with increasing the annealing temperature, reaches a maximum at 500?°C and then starts decreasing with further increase in annealing temperature, which indicating that the controllable ZnO/Graphene thin films have the higher crystallization quality at the annealing temperature of 500?°C. Our results demonstrate that for high quality ZnO/graphene thin films deposition, decreasing the defect concentration should be preferable to simply applying the proper annealing temperature, which might have promising applications for various UV photodetectors devices.     

薄膜二次锂离子电池正极研究进展

薄膜二次锂离子电池是锂离子电池发展的最新领域,正极材料的薄膜化是薄膜二次锂离子电池的重要部分.综述了近年来发展的一些薄膜正极的制备方法,包括溶胶-凝肢法(Sol-gel)、化学沉积法(CVD)、激光高温灼烧法(LA)、脉冲激光沉积法(PLD)、射频磁控溅射法(RMP),对各种方法的优缺点进行了比较,并对正极薄膜制备的发展方向进行了展望.     

Growth of MgTiO3 thin films by pulsed laser deposition and their electrical properties

Abstract

MgTiO₃ thin films have been grown on various substrates by pulsed laser deposition (PLD) to investigate the application for microwave dielectrics and optical devices. Highly oriented MgTiO₃ thin films were obtained on sapphire (c-plane Al₂O₃). MgTiO₃ thin films deposited on SiO₂/Si and platinized silicon (Pt/Ti/SiO₂/Si) substrates were polycrystalline nature. MgTiO₃thin films grown on sapphire were transparent in the visible and had a sharp absorption edge at 280 nm. These MgTiO₃ thin films had extremely fine feature of surface morphology, i.e., rms roughness of 0.87 nm. Dielectric constant and loss of MgTiO₃ thin films deposited by PLD were about 24 and 1.5% at 1MHz, respectively. These MgTiO₃ thin films also exhibited little dielectric dispersion.     

ZnO/TiO2复合薄膜的制备及性能表征

采用溶胶凝胶法结合丝网印刷法制备TiO2多孔薄膜,用溶液沉积法制备多孔ZnO/TiO2复合薄膜;用X-射线分析仪、扫描电镜、紫外-可见分光光度计等对薄膜的热处理制度、吸光度、表面形貌进行了测试;组装电池,用XJCM-8S型太阳电池测定仪测定了复合薄膜的电性能.结果表明以ZnO/TiO2复合薄膜做电极,吸光度和电池性能都有一定的提高,电池电压达到0.67 V.     

热电池用正极-电解质一体化复合薄膜的制备及性能研究

面向新一代小型化轻量化武器装备对热电池电源的实际需求,通过流延涂布工艺制备了正极-电解质一体化复合薄膜极片.所制备的一体化薄膜具有良好的机械强度,极片厚度仅为180 mm,远小于传统粉末压片工艺制得极片的厚度.将一体化薄膜极片与锂硼负极组装成单体电池进行放电,放电结果表明,在100 mA/cm2的电流密度下,450℃时...     

Nanoscale phenomena of gallium-doped ZnO thin films on sapphire substrates

Gallium-doped ZnO (1.2 at. %) thin films with various thicknesses were deposited on sapphire (001) substrates at 500^∘C using a pulsed laser deposition (PLD) technique. The thin films with different thicknesses (20, 40, 100, 200, 400, and 600 nm, respectively) were obtained by changing the deposition time. An x-ray diffractometer (XRD) was used to investigate the structural properties of the thin films. All of the thin films had a preferred (002) orientation. However, the thin films with 20 and 40 nm thicknesses were of low crystallinity. With increasing thickness the (002) peak increased greatly, and the full width at half maximum (FWHM) values were calculated by using omega scans. Scanning electron microscope (SEM) and atomic force microscope (AFM) were used to investigate the nanoscale phenomena and the surface morphologies of the thin films. The surface roughness increased as the thickness increased. The thin film with 20 nm thickness was very smooth, and no nucleation center could be observed. However, the thin film with thickness over 100 nm showed nucleation. The nucleation center varied with increasing thickness. A spectrometer was used to investigate the luminescent properties of the thin films. It was found that all of the thin films showed near band edge emissions and no deep-level emissions were observed. A blueshift was also observed due to the Burstein-Moss effect.     

Anti-bacterial biofilm activity of magnesium ferrite thin film

ABSTRACT

Thin films of magnesium ferrite (MgFe₂O₄) are synthesized on the glass substrate by using thermal evaporation technique and studied their anti-bacterial biofilm activity against the gram-negative and gram-positive bacterium. The MgFe₂O₄ thin films (100 nm) were prepared at a deposition rate of 10 ± 2 Å/S, followed by annealing at 600°C. The morphological and structural study using scanning electron microscope, X-ray diffraction, and transmission electron microscope reveals crystalline structure of the magnesium ferrite. The model organisms for anti-bacterial biofilm activity were tested with E. coli (gram negative) and S. aureus (gram positive). The E. coli and S. aureus biofilms grown on the glass slides and MgFe₂O₄ coated glass slide were imaged using fluorescent microscope. It is observed that the MgFe₂O₄ coated glass slides exhibit minimum bacterial growth (both negative and positive bacteria) compared to the uncoated glass slide.     

SmTbCo/Cr薄膜的磁特性与温度特性研究

采用射频磁控溅射法在玻璃基片上成功地制备了SmTbCo/Cr非晶垂直磁化膜,对薄膜的磁特性与温度特性进行了研究.薄膜组分为(Sm0.286Tb0.714)31Co69/Cr时,其饱和磁化强度为330kA/m,矫顽力为398kA/m,薄膜的磁各向异性能值高达415kJ/m3;该种薄膜的居里温度在220℃左右,补偿温度在室...