A system for supplying constant electrical power for postprocessing tin-doped indium oxide films

Annealing tin doped indium oxide (ITO) thin films by self-heating shows potential for reducing the crystallization temperature required to optimize the optical and electrical properties of the films. It also shows promise as a cost effective method of studying the heat treatment process in situ. A computer based solution was developed to allow for a precise control over the annealing process. To anneal at a fixed temperature, a feedback loop senses changes in the resistance of the sample and adjusts the current across the load accordingly to ensure constant delivery of power to an ITO film.     

锑掺杂纳米SnO2透明导电薄膜的制备与性能研究

采用溶胶-凝胶法在Si片、已镀SiO2的钠钙硅玻璃和普通钠钙硅玻璃上镀Sb掺杂摩尔分数为8%的SnO2薄膜(ATO),在450℃热处理温度下对薄膜结构,电学、光学性能进行表征。结果表明:薄膜以四方金红石结构存在,结晶完全;方阻值随镀膜层数的增加而明显降低,12层时薄膜最低方阻值为129Ω/□,可见光平均透过率在75%以上。随着波长的增大,红外波段的反射率逐渐增大,从15%增加到55%左右。     

透明导电ITO薄膜的制备及光电特性的研究

采用溶胶-凝胶方法以In（NO3）3.4·5H2O和SnCl4·5H2O为前驱物,用提拉法在石英玻璃基体上制备了ITO透明导电薄膜。详细研究了不同掺Sn比例、不同金属离子浓度、不同提拉速度、不同烘烤温度对ITO薄膜光电特性的影响。结果表明,提拉法制备的薄膜在热处理过程中由凝胶状态向结晶态逐渐转变,方电阻随热处理温度的升高而降低;导电率随薄膜厚度的增加呈非线性增加。     

The role of substrates on the structural,optical, and morphological properties of zno nanotubes prepared by spray pyrolysis

ZnO films were deposited onto glass, ITO coated glass, and sapphire substrate by spray pyrolysis, and subsequently annealed at the same temperature of 400°C for 3 h. The role of substrate on the properties of ZnO films was investigated. The structural and optical properties of the films were investigated by X‐ray diffractometer (XRD) and photoluminescence (PL) spectrophotometer, respectively. The surface morphology of the nanostructured ZnO film was investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Crystallographic properties revealed that the ZnO films deposited on sapphire and ITO substrates exhibit a strong c‐axis orientation of grains with hexagonal wurtzite structure. Extremely high UV emission intensity was determined in the film on ITO. The different luminescence behaviors was discussed, which would be caused by least value of strain in the film. Films grown on different substrates revealed differences in the morphology. ZnO films on ITO and sapphire substrates revealed better morphology than that of the film on glass. AFM images of the films prepared on ITO show uniform distribution of grains with large surface roughness, suitable for application in dye sensitized solar cells. Microsc. Res. Tech. 77:211–215, 2014. © 2013 Wiley Periodicals, Inc.     

真空热处理对硫化锌薄膜光学与微结构特性的影响

针对电子束蒸发离子辅助沉积的硫化锌薄膜,研究了550℃以下真空热处理对其光学与微结构特性的影响。薄膜光学和微结构特性的测试分析表明:制备后薄膜为类立方结构的ZnS,在337.5nm波长处出现临界特性转折点,随着热处理温度的增加,转折波长两侧的消光系数变化规律相反,折射率和物理厚度呈现下降趋势,薄膜的禁带宽度逐渐增加;在红外波段的薄膜折射率与热处理温度的变化并不显著,在350℃下热处理时消光系数出现转折,主要是由晶粒变小的趋势所致;通过晶相分析,硫化锌薄膜经历了类立方结构到六方结构的转换,与禁带宽度的变化趋势基本一致。分析结果表明,光学特性变化的根本原因是薄膜的微结构特性变化。     

Investigation of CdS thin films by a near-field microwave microprobe

Cadmium sulphide (CdS) thin films with different microstructures and morphologies were measured by using a near-field microwave microprobe (NFMM). The NFMM system was coupled to a dielectric resonator with a distance regulation system at an operating frequency f=4.1GHz. The changes in dielectric permittivity of CdS thin films due to different annealing temperatures were investigated by measuring the reflection coefficient S(11). CdS thin films with different microstructures and morphology were characterized by X-ray diffraction, atomic force microscopy and NFMM.     

Investigation of thermoelectric silicide thin films by means of analytical transmission electron microscopy

The microstructure of rhenium silicide thin films and its progress by annealing were investigated by means of analytical transmission electron microscopy. Sputtered amorphous films were characterised by analysis of the radial distribution function (RDF). The position of the first maximum of RDF represents the most probable distance between neighbouring atoms and decreases from 2.75 to 2.62 A in films with an increasing Si-content from 60 to 75 at%. This decrease correlates with the change of the temperature coefficient (TC) of the electrical resistivity. During in situ annealing, the formation of nanocrystals in films with different Si-contents was observed. In thin films with 64 at% the quantity of nanocrystals increases after 1 h at 900 K whereas their sizes remain unchanged. The crystallisation in Re-rich thin films proceeds lower and produces larger crystals than in films near to the ReSi1.75 stoichiometry. Sputtered epitaxial ReSi1.75 films on Si (1 0 0) consist of crystals with nanometer size and an azimuthal torsion of 45 degrees.     

Growth and characterization of V2O5 thin film on conductive electrode

Vanadium pentoxide V₂O₅ thin films were grown at room temperature on ITO coated glass substrates by electrochemical deposition. The resulting films were annealed at 300, 400 and 500°C for 1 h in ambient environment. The effect of heat treatment on the films properties such as surface morphology, crystal structure, optical absorption and photoluminescence were investigated. The x‐ray diffraction study showed that the films are well crystallized with temperatures. Strong reflection from plane (400) indicated the film's preferred growth orientation. The V₂O₅ films are found to be highly transparent across the visible spectrum and the measured photoluminescence quenching suggested the film's potential application in OPV device fabrication.     

热处理条件对溅射法制得的InSb薄膜特性的影响

文中从理论和实验分析了热处理条件对溅射法制得的ＩｎＳｂ薄膜特性的影响。热处理温度、时间和升降温速率都对薄膜特性有影响,通过实验得出了最佳的热处理温度、恒温时间和升降温速率。最后讨论了热处理过程中所采用的３种保护膜。     

基于薄膜退火的MoS_2/SiO_2/Si异质结太阳能电池光伏性能提高

为了制备高效的MoSi/SiO_2/Si异质结太阳能电池,利用磁控溅射技术制备MoS_2薄膜,并在硫气氛下对MoS_2薄膜进行退火处理。分别用退火和未退火的MoS_2薄膜制备MoS_2/SiO_2/Si异质结太阳能电池,研究了退火对MoS_2薄膜的微观结构和MoS_2/SiO_2/Si异质结太阳能电池光电性能的影响。实验结果显示,相比于未退火的,经过退火处理的MoS_2薄膜的拉曼峰半高宽(FWHM)变窄,峰强增强,显微荧光光谱中也出现明显的激子发光峰。由此表明,退火处理使MoS_2薄膜由非晶向晶态转变,薄膜的体缺陷减少,异质结太阳能电池的开路电压和填充因子得到提升,器件转换效率从0.94%提高到1.66%。不同光照强度下的J-V测量和暗态的J-V测量结果表明,经退火处理的MoS_2薄膜的异质结太阳能电池具有较高的收集电压和更接近于1的理想因子,这归因于退火导致MoS_2薄膜的体缺陷的减少,近而降低了MoS_2/SiO_2/Si异质结太阳能电池器件的体缺陷复合。     

Evaluation of surface roughness and nanostructure of indium tin oxide (ITO) films by atomic force microscopy

Indium tin oxide was deposited on a glass (soda lime glass) by radiofrequency sputtering system at different sputtering gas (argon/oxygen 90/10%) pressures (20-34 mTorr) at room temperature. The sputtering rate was affected by the sputtering gas pressure. The optimum sputtering gas pressure was found to be 27 mTorr. The samples at different thicknesses (168, 300, 400, 425, 475, 500 and 630 nm) were deposited on the substrate. Transparency, electrical conductivity and surface roughness of the films were characterized. The samples were annealed at 350, 400 and 450 degrees C to evaluate annealing process effects on the concerned parameters and, therefore, the above-mentioned measurements were repeated again. The films exhibited reasonable optical transmittance and electrical conductivity and greatly improved after annealing. The characterization was focused on the scanning of the film surfaces before and after annealing, which has a prominent effect on the optical properties of the films. Film surfaces were scanned by scanning probe microscopy in contact atomic force mode. The most consideration was devoted to image analysis.     

退火温度对二氧化钛薄膜的性能影响

为了获得性能优良的二氧化钛薄膜,采用电子束蒸发沉积方法制备二氧化钛薄膜,并分别在300、600、900℃空气中对样品进行退火处理以改善所制备二氧化钛薄膜的性能。分别采用X射线衍射(XRD)、原子力显微镜(AFM)以及分光光度计研究了退火温度对二氧化钛薄膜结构和光学性能的影响。结果表明,退火处理可以使二氧化钛薄膜由非晶态薄膜转换为金红石型薄膜,且金红石晶型成分随退火温度的加大而增大,同时退火处理可以改善二氧化钛薄膜在300~1 200nm光谱范围的总吸光率以及增大二氧化钛薄膜的应用范围。     

磁控溅射Ni56Mn27Ga17合金薄膜的光学反射特性研究

Ni-Mn-Ga磁性形状记忆合金薄膜是非常有用的多功能材料,为考察其光学反射特性,采用磁控溅射技术在单晶硅衬底上沉积了Ni56Mn27Ga17合金薄膜,并对其表面形貌和光学反射特性进行研究。研究结果表明,薄膜的表面粗糙度随退火温度的升高而增大;在300～800nm波长范围内,薄膜反射率均随波长的减小而降低,且薄膜整体谱线范围内的反射率随退火温度的升高而降低。     

退火时间对Cu-Al-O薄膜性能影响的研究

通过制备Cu-Al-O薄膜并对其进行退火处理,研究了退火时间对薄膜形貌、结构以及紫外-可见透过率、带隙、中红外透过率的影响。研究结果表明:随着退火时间的增加,薄膜开始晶化,5.0 h时薄膜中出现裂纹,同时出现AlCu合金相;紫外-可见透过率随退火时间的增加而降低;中红外透过率随退火时间的增加先增加后降低;Cu-Al-O薄膜的直接带隙随退火时间的增加而降低。     

Friction coefficient and wear rate of sputter-deposited thin films and plasma-sprayed thick coatings at high temperatures in room air

Silver, calcium fluoride (CaF_x with x = 1.85) and chromium-carbon (Cr₃C₂) thin films were deposited onto various tribological test specimens by sputtering. The friction properties of sputter-deposited Ag and CaF_x single layers as well as Ag/CaF_x multilayer films were determined by ball-on-disk tribological tests conducted in room air under various experimental conditions. The tribological properties (friction coefficient and wear rate) of sputter-deposited CaF_x films were also determined at 500°C by pin-on-disk tribological tests performed with pin specimens made of cobalt-based alloy (alacrite). Chromium-carbon films sputter-deposited onto alacrite disk and counterfaces were found to be of interest for reducing the formation of alacrite wear debris in the wear tracks; thus reduced friction coefficient and wear rate values were obtained. The friction behavior of sputter-deposited CaF_x/Cr₃C₂ thin bilayer structures and plasma-sprayed (PS) chromium carbide/Ag/BaF₂-CaF₂ eutectic composite coatings (PS-212 type coatings) was investigated by plane-on-plane tribological tests conducted in room air at 500°C and 700°C. The friction performance of solid lubricant thin bilayer films was compared with that of thick PS-212 type coatings similar to coatings developed by NASA.     

酞菁铜薄膜气敏光谱性能的研究

用真空升华方法制备酞菁桐（CuPc）薄膜，并测量了薄膜在不同浓度的NH3和乙醇气体中的透射光谱。实验发现CuPc薄膜对NH3浓度的变化有良好的响应，但乙醇浓度的变化不够敏感，特别是在高浓度时；退火处理不能改善膜片乙醇的敏感性能，而使膜片对NH3的响应变差。     

Advances in phase‐sensitive acoustic microscopy studies of polymer blend films: annealing effects and micro‐elastic characterization of PS/PMMA blends

The unique phase‐sensitive acoustic microscope is used for the structural and mechanical characterization of thin films of polystyrene/polymethylmethacrylate blends. The effect of annealing on blends of polystyrene/polymethylmethacrylate spin coated from different solvents unto a substrate is studied. Varying the solvents according to vapour pressure and spin coating at different speeds (for thickness variation) led to changes in phase domain distributions and overall structural properties before annealing. Annealing in vacuum at 190°C for 48 h resulted in the elimination of solvent effects with all samples reverting to a similar morphology irrespective of common solvent and thickness. The Young's moduli at specific points on the film (E_polystyrene= 3.4 ± 0.3 GPa, E_{polymethylmethacrylate}= 4.2 ± 0.4 GPa) and over a given area (E_{polystyrene/polymethylmethacrylate}= 3.9 ± 0.4 GPa) were determined by combinatory use of the atomic force microscope and phase‐sensitive acoustic microscope. These results demonstrate a minimally invasive method for the quantitative characterization of polymer blend films.     

Synthesis and microstructural studies of annealed Cu2O/CuxS bilayer as transparent electrode material for photovoltaic and energy storage devices

Cu₂O thin film and a transparent bilayer have been fabricated by electrodeposition method. The growths were obtained in potentiostatic mode with gradual degradation of anodic current. X‐ray diffraction (XRD) study showed that the bilayer is polycrystalline and it possesses mixture of different crystallite phases of copper oxides. Surface morphology of the films was investigated by scanning electron microscopy (SEM). The SEM images revealed that the films were uniformly distributed and the starting material (Cu₂O) had cubical structure. Grains agglomeration and crystallinity were enhanced by annealing. Optical studies indicated that all the samples have direct allowed transition. Energy band gap of the bilayer film was reduced by annealing treatment thus corroborating quantum confinement upshot.     

Characterization of lead zirconate titanate--lanthanum ruthenate thin film structures prepared by chemical solution deposition

In this work, the results of compositional and microstructural analysis of lead zirconate titanate--lanthanum ruthenate thin film structures prepared by chemical solution deposition are discussed. The cross-section transmission electron microscope (TEM) micrographs of the La-Ru-O film deposited on a SiO2/Si substrate and annealed at 700 degrees C revealed RuO2 crystals embedded in a glassy silicate matrix. When the La-Ru-O film was deposited on a Pt/TiO2/SiO2/Si substrate, RuO2 and La4Ru6O19 crystallized after annealing at 700 degrees C. After firing at 550 degrees C randomly oriented lead zirconate titanate (PZT) thin films crystallized on the La-Ru-O/SiO2/Si substrate, while on La-Ru-O/Pt/TiO2/SiO2/Si substrates PZT thin films with (111) preferred orientation were obtained. No diffusion of the Ru atoms in the PZT film was found. Ferroelectric response of PZT thin films on these substrates is shown in comparison with the PZT film deposited directly on the Pt/TiO2/SiO2/Si substrate without a La-Ru-O layer.     

Morphological properties of Ag₂SeTe nano thin films prepared by thermal evaporation

Semiconducting silver selenide telluride (Ag₂SeTe) thin films were prepared with different thicknesses onto glass substrates at room temperature using thermal evaporation technique. The structural properties were determined as a function of thickness by X‐ray diffraction exhibiting no preferential orientation along any plane; however, the films are found to have peaks corresponding to mixed phase. The morphology of these films was studied using scanning electron microscope and atomic force microscopy respectively, and is reported. The morphological properties are found to be very sensitive to the thin film thickness. The composition of the films is also estimated using energy dispersive analysis using X‐rays and are also reported.