钇钡铜氧超导薄膜光诱导弛豫特性研究

采用TFA-MOD法在LaAlO3(LAO)单晶基底上制备了钇钡铜氧(YBCO)超导薄膜,利用X射线衍射对YBCO超导薄膜的结构进行了表征,并对其最佳沉积工艺进行了分析;研究了YBCO薄膜在不同温度和不同光功率下的光诱导特性.在光诱导下,YBCO薄膜出现了明显与电子体系相关的弛豫现象,说明薄膜的光致电阻变化与激光的功率...     

Effect of pulsed laser annealing on optical and structural properties of ZnO:Eu thin film

Journal of Materials Science - ZnO:Eu thin film fabricated by pulsed laser deposition was treated by pulsed UV laser. The effect of laser fluence from 70 to 125 mJ cm?2 on film...     

Matrix-Assisted Pulsed Laser Evaporation of polythiophene films

Organic poly-conjugated systems have recently attracted great interest as semi-conducting materials and, among poly-conjugated systems, substituted polythiophenes have given relevant results in PVs applications. The high conductivity required is affected by both the polymer conjugation length and the chain packing. Thus, highly region-regular polymers must be used and deposited as thin films with some technique which favours orientation and crystallization of the polymer chains.A deposition technique often used for its flexibility and high control over film characteristics is Pulsed Laser Deposition (PLD). In PLD, largely applied for inorganic thin film deposition, the material is ablated from a solid target by a focused pulsed laser beam and is deposited on the substrate placed at a small distance. Although some addition polymers have been successfully deposited the deposition seems to proceed via a “depolymerization-monomer ablation-repolymerization” mechanism, this is clearly not possible in general for organic molecules and condensation polymers.On the contrary MAPLE (Matrix-Assisted Pulsed Laser Evaporation) is a recently developed PLD based thin film deposition technique, particularly well suited for organic/polymer thin film deposition. Up to now MAPLE depositions have been carried out mainly by means of modified PLD systems, using excimer lasers operating in UV, but use of less energetic radiations can minimize the photochemical decomposition of the polymer molecules.We have used a deposition system explicitly designed for MAPLE technique connected to a Q-switched Ng:YAG pulsed laser which can be operated at different wavelength ranging from IR to UV in order to evaluate the effect of the choice of laser radiation on the deposition of POOPT thin films.From DRIFT-IR spectroscopy, all deposited films showed structural order; it was determined that the better wavelength for POOPT deposition is 532 nm. With this value of the laser wavelength the local chemical structure of the polymer was retained and the film appeared more homogeneous.     

Etching processes of transparent carbon nanotube thin films using laser technologies

Carbon nanotubes (CNTs) have potential as a transparent conductive material with good mechanical and electrical properties. However, carbon nanotube thin film deposition and etching processes are very difficult to pattern the electrode. In this study, transparent CNT film with a binder is coated on a PET flexible substrate. The transmittance and sheet resistance of carbon nanotube film are 84% and 1000 Ω/□, respectively. The etching process of carbon nanotube film on flexible substrates was investigated using 355 nm and 1064 nm laser sources. Experimental results show that carbon nanotube film can be ablated using laser technology. With the 355 nm UV laser, the minimum etched line width was 20 μm with a low amount of recast material of the ablated sections. The optimal conditions of laser ablation were determined for carbon nanotube film.     

脉冲激光沉积技术制备薄膜锂电池

脉冲激光沉积(pulsed laser deposition,PLD)是20世纪80年代发展起来的一种全新的制备薄膜技术,具有沉积速率高,再现性能好等优点.近年来,利用PLD技术在全固态薄膜锂电池的研究中取得许多有意义的结果.一系列新型、高质量的电池薄膜材料被成功制备;原位组装的薄膜锂电池表现出良好的电化学性能.本文简要介绍了PLD技术的原理和特点;重点评述PLD在全固态薄膜锂电池阴极薄膜、阳极薄膜和电解质薄膜制备中的应用状况.     

微锂电池用LiCoO2薄膜研究进展

本文简述了LiCoO2在粉体和薄膜中晶体结构与电化学性能；详细介绍了钴酸锂薄膜的制备方法并评述了不同合成方法、制备条件对钴酸锂薄膜结合强度、结构、形貌及电化学性能的影响，指出脉冲激光沉积法是一项值得深入研究的钴酸锂薄膜制备技术。     

薄膜型锂离子电池正极材料研究进展

简要介绍了近年来磁控溅射和脉冲激光沉积制膜技术在薄膜型锂离子电池正极材料制备方面的应用研究; 对制膜新工艺及新型正极材料的研究现状进行了概括,认为现阶段新型材料LiFePO4有希望成为薄膜锂电池正极材料的首选,并展望了薄膜型锂离子电池的发展前景.     

UV optical properties of thin film oxide layers deposited by different processes

UV optical properties of thin film layers of compound and mixed oxide materials deposited by different processes are presented. Japan Electron Optics Laboratory plasma ion assisted deposition (JEOL PIAD), electron beam with and without IAD, and pulsed DC magnetron sputtering were used. Comparisons are made with published deposition process data. Refractive indices and absorption values to as short as 145 nm were measured by spectroscopic ellipsometry (SE). Electronic interband defect states are detected that are deposition-process dependent. SE might be effective in identifying UV optical film quality, especially in defining processes and material composition beneficial for high-energy excimer laser applications and environments requiring stable optical properties.     

A comparative study of the UV optical and structural properties of SiO2, Al2O3, and HfO2 single layers deposited by reactive evaporation, ion-assisted deposition and plasma ion-assisted deposition

Growing requirements for the optical and environmental stability, as well as the radiation resistance against high-power laser radiation, especially for optical interference coatings used in the ultraviolet spectral range, have to be met by new, optimised, thin-film deposition technologies. For applications in the UV spectral range, the number of useful oxide thin film materials is very limited due to the higher absorption at wavelengths near to the electronic bandgap of the materials. Applying ion-assisted processes offers the ability to grow dense and stable films, but in each case careful optimisation of the deposition process (evaporation rate, substrate temperature, bombarding gas, ion energy and ion current density) has to achieve a balance between densification of the layers and the absorption. High-quality coatings and multilayer interference systems with SiO₂ as the low-index material can be deposited by various physical vapour deposition technologies, including reactive e-beam evaporation, ion-assisted deposition and plasma ion-assisted deposition. In order to improve the degradation stability of dielectric mirrors for use in UV free-electron laser optical cavities, a comparative study of the properties of SiO₂, Al₂O₃ and HfO₂ single layers was performed, and was addressed to grow very dense films with minimum absorption in the spectral range from 200 to 300 nm. The films were deposited by low-loss reactive electron-beam evaporation, by ion-assisted deposition using a ‘Mark II’ ion source, and by plasma ion-assisted deposition using the advanced plasma source. Optical and structural properties of the samples were studied by spectral photometry, infrared spectroscopy, X-ray diffraction and reflectometry, as well as by investigation of the surface morphology. The interaction of UV radiation with photon energy values close to the bandgap was studied. For HfO₂ single layers, laser-induced damage thresholds at 248 nm were determined in the 1-on-1 and 1000-on-1 test modes as a function of the deposition technology and film thickness.     

脉冲激光沉积有机薄膜

脉冲激光沉积(PLD)技术是一门新兴的薄膜制备技术,在无机薄膜的制备和研究方面取得了令人满意的成果,技术也比较成熟.但利用脉冲激光沉积技术制备和研究有机膜方面的工作开展较晚,工作也比较少,尚未形成一个比较系统的体系.因此开展有机薄膜的脉冲激光沉积研究将具有重要的意义.     

Photocatalytic TiO(2) deposition by chemical vapor deposition

Dip-coating, spray-coating or spin-coating methods for crystalline thin film deposition require post-annealing process at high temperature. Since chemical vapor deposition (CVD) process is capable of depositing high-quality thin films without post-annealing process for crystallization, CVD method was employed for the deposition of TiO(2) films on window glass substrates. Post-annealing at high temperature required for other deposition methods causes sodium ion diffusion into TiO(2) film from window glass, resulting in the degradation of photocatalytic efficiency. Anatase-structured TiO(2) thin films were deposited on window glass by CVD, and the photocatalytic dissociation rates of benzene with CVD-grown TiO(2) under UV exposure were characterized. As the TiO(2) film deposition temperature was increased, the (112)-preferred orientations were observed in the film. The (112)-preferred orientation of TiO(2) thin film resulted in a columnar structure with a larger surface area for benzene dissociation. Obviously, benzene dissociation rate was maximum when the degree of the (112) preferential orientation was maximum. It is clear that the thin film TiO(2) should be controlled to exhibit the preferred orientation for the optimum photocatalytic reaction rate. CVD method is an alternative for the deposition of photocatalytic TiO(2).     

HIGH Tc SUPERCONDUCTING THIN FILM DEPOSITION BY LASER INDUCED FORWARD TRANSFER

We review in this paper the basic mechanisms and potential applications of the Laser Induced Forward Transfer (LIFT) for the rapid deposition and patterning in a clean environment, of high Tc superconducting thin films. A stoichiometric oxide superconductor compound is initially deposited, in a thin layer, on an optically transparent support. By irradiating, under vacuum or in air, this precoated layer with a strongly absorbed single laser pulse through the transparent support, the film is removed from its support to be transferred onto a selected target substrate, held in contact or close to the original film. The mechanisms for transferring YBaCuO and BiSrCaCuO thin films, with a pulsed UV excimer laser are described using a thermal melting model based on the resolution of the heat flow equation. The various possibilities given by the LIFT technique for patterning high Tc films (mask and direct patterning) are also examined.     

Relationship between ultraviolet emission and electron concentration of ZnO thin films

ZnO thin films were deposited on (0001) Al₂O₃ substrates depending on oxygen partial pressure by pulsed laser deposition. Optical properties of ZnO were investigated by photoluminescence (PL). The relationship between PL and electron concentration has been investigated. Origin of the dominant ultraviolet (UV) emission in ZnO thin film measured at room temperature was identified as a free electron-neutral-acceptor transition (eA⁰) through temperature dependence of PL measurement. The UV emission intensity at room temperature is related to variation of electron concentration because a free-electron-neutral-acceptor transition (eA⁰) as origin of UV emission at room temperature is related to impurity concentration of ZnO.     

Kesterite based thin film absorber layers from ball milled precursors

The existing thin film technology involves rare earth and toxic materials. Cu₂ZnSnS₄, its selenide and sulfo selenide analogues have acquired as the most promising alternate absorber material group in thin film technology due to the abundance and non toxic constituent elements. We present a facile, green and low cost method for synthesis of CZTS/(Se) films. Precursor powders using Cu, Zn, Sn, S and Se, was prepared by ball milling. Starting with ball milled metallic precursor powders we synthesized kieserite thin films by doctor blade coating process and subsequent annealing. Doctor blade coating method is one of the cheapest non toxic non vacuum based chemical deposition processes. A comparative study of ball milled powder and films prepared from the precursors has been presented and interesting aspects of structure, morphology and composition were explored after ball milling, and films formed after annealing. Chalcogens (S or Se) plays an important role in the construction of tetragonal phase. A combined TGA–DSC, X-ray diffraction, Raman, TEM, EDX and UV–Vis–NIR study showed marked change in film property after annealing.     

Imposed layer-by-layer growth of ZnO on GaN/sapphire substrates using pulsed laser interval deposition

The oxide semiconductor ZnO is of high interest for electrooptical applications due to its direct and wide band gap in the UV region. We present our results on pulsed laser deposition growth of ZnO on GaN-buffered Al₂O₃ substrates. Using in-situ reflection high energy electron diffraction, intensity oscillations were recorded and used to apply the technique of interval deposition. A significant improvement of structural thin film quality was achieved due to the expansion of the high quality from the first layers to the whole film thickness.     

在聚酰亚胺衬底上低温制备超薄热敏铂膜的研究

通过在聚合物衬底上制备热敏薄膜可以实现非平、屈曲物体表面温度的实时监控和测量。利用脉冲激光沉积技术在聚酰亚胺衬底上低温（250℃左右）制备了超薄铂热敏薄膜,其室温下的电阻温度系数为1．01×10^-3／K。通过增加ZnO过渡层,可使铂薄膜的电阻温度系数增大为1．55×10^-3／K。     

Evaporated nanostructured Y2O3:Eu thin films

Europium-doped yttrium oxide (Y2O3:Eu) is a well-known luminescent material that in recent years has been studied in thin-film form. However, to date there has not been a great effort put into altering the nanostructure of these films. A thin-film deposition technique called glancing angle deposition allows for a high degree of control over the nanostructure of the thin film, resulting in thin films with nanostructure geometries ranging from chevron and post to helix. Glancing-angle deposition was used to make europium-doped yttrium oxide thin films with slanted-post nanostructures. Portions of the films were annealed in air at 850 degrees C for 10 hours following deposition. Scanning electron microscopy was used to characterize the nanostructures of the films, while UV laser excitation was used to characterize the photoluminescence properties of the films. The annealed samples exhibited increased photoluminescent responses compared to unannealed samples; however, the porous nanoscale geometry of the films was unaffected. In order to optimize the photoluminescence properties of the films, both the partial pressure of oxygen during film deposition and the level of europium doping in the source material used were varied. Films fabricated from the source material with a greater amount of europium doping had larger photoluminescent responses, while the optimal partial pressure of oxygen during electron-beam evaporation was found to be less than 1.0 x 10(-4) torr.     

脉冲激光薄膜制备技术

脉冲激光薄膜沉积是近年来受到普遍关注的制膜新技术。简要介绍了脉冲激光薄膜沉积技术的物理原理、独具的特点和研究发展动态,并介绍了采用脉冲激光薄膜沉积技术制备硅基纳米PtSi薄膜的结果     

脉冲激光沉积(PLD)薄膜技术的研究现状与展望

综述了脉冲激光沉积 (PLD)薄膜技术的研究现状 ,并按照研究方向将整个研究领域分为三个部分 :PLD法沉积薄膜的机理 ,PLD的工艺研究以及PLD法沉积的主要薄膜材料 ,分别进行了阐述 ,对相关的研究工作提出了建议 ,并对PLD技术的应用前景做了展望     

TiO2功能薄膜的制备及影响其光催化活性的因素

近些年来，TiO2功能薄膜以其卓越的性能，尤其是优异的光催化性能引起研究人员的广泛关注，本文根据国内外近期TiO2功能薄膜的研究现状，对化学气相沉积法，水解一沉淀法，液相沉积法，溶胶－凝胶法，原子层沉积法，溅射法，激光辅助分子束沉积法等化学和物理制备方法进行评述，并比较详细地探讨了表面羟基含量，膜的厚度和孔径，结晶形态，基片种类，掺杂和光强度等因素对TiO2薄膜光催化性能的影响。