ITO薄膜光电性能红外-可见光谱分析方法

研究了射频磁控溅射制备ITO薄膜,利用四探针方法、分光光度计测试薄膜面电阻及红外-可见光光谱,利用光谱特征研究了不同工艺对薄膜面电阻、载流子浓度、折射率等光电性能的影响.研究表明,随温度的升高ITO薄膜面电阻减小,载流子浓度增加,折射率减小,透过率增加;随氧分压的增加面电阻增大,载流子浓度减小.     

热处理对Sb∶SnO_2透明导电薄膜光电性能的影响

由烧结法制备了5Sb_2O_5·95SnO_2(mol%)陶瓷靶材,以所制靶材利用射频磁控溅射法在石英玻璃基片上制备得到高质量的Sb∶Sn O2(ATO)透明导电薄膜,研究了热处理温度对ATO薄膜的结构和光学与电学性能的影响。结果表明:热处理对ATO薄膜的相结构,结晶质量及性能均有一定的影响。随着温度升高,所制薄膜的晶粒尺寸逐渐长大,方块电阻逐步减小,最小值为9.3Ω/;红外反射率先增大后减小,并在热处理温度为600℃时达到极大值,为89%。薄膜可见光透过率均在80%以上,温度为600℃时最高达到91.3%。     

直流磁控溅射工艺对ITO薄膜光电性能的影响

采用直流磁控溅射系统在玻璃衬底上制备了氧化铟锡(ITO)薄膜。通过X射线衍射仪、扫描电子显微镜、分光光度计、Hall效应测试系统研究了热退火与原位生长、衬底温度、直流溅射功率对薄膜结构、表面形貌以及光电性能的影响。结果表明:与室温生长并经410℃热退火后的薄膜相比,410℃原位生长可获得光电性能更好的薄膜;随着衬底温度的增加,电阻率单调减小,光学吸收边出现蓝移;在溅射功率为85 W时薄膜的光电性能达到最佳。在衬底温度为580℃、溅射功率为85 W的工艺条件下,可制备出电阻率为1.4×10~(–4)?·cm、可见光范围内平均透过率为93%的光电性能优异的ITO薄膜。     

铁电薄膜存储器底电极Pt/Ti的制备及性能研究

应用射频磁控溅射方法 ,在Si基片上采用不同的溅射工艺制备了铁电薄膜底电极Pt/Ti,并分析了在不同温度下退火后材料的电导率性能和粘结力性能 ,从理论和实验上分析了不同的溅射工艺和退火处理对底电极性能的影响。     

空气和氮气气氛中热处理温度对ITO薄膜性能影响

以InCl_3·4H_2O和SnCl_4·5H_2O为主要原料,采用溶胶-凝胶法和旋转涂膜工艺。在玻璃基片上制备掺锡氧化铟透明导电薄膜(ITO),采用x-射线粉末衍射、紫外-可见透射光谱和四探针技术,研究了在空气和氮气气氛中,不同热处理温度对ITO薄膜的微结构、光学和电学性能的影响。     

工艺因素对磁控溅射法制备钛酸锶钡薄膜性能的影响

磁控溅射技术在薄膜制备领域有着广泛的应用.本文在介绍磁控溅射法制备薄膜材料的基本原理和流程基础之上,详细分析了溅射工艺参数(溅射功率、温度、溅射气压、氧分压)对BST薄膜性能的影响,并提出了研究中需要解决的一些问题.     

沉积温度对AZO薄膜性能的影响

在采用直流磁控溅射制备AZO(Aluminum Doped Zinc Oxide,掺铝氧化锌)薄膜的过程中,AZO薄膜的光电性能取决于镀膜过程中的各种工艺参数,包括溅射气压、沉积温度、溅射功率和靶基距等。本文主要研究在固定其它工艺参数不变的情况下,通过改变沉积温度在不同的温度下分别制备AZO薄膜,利用SEM、X射线衍射仪等测试不同AZO薄膜的微观结构,并分析研究不同沉积温度下制备AZO薄膜光电性能及结构的变化特性,以筛选出制备高质量AZO膜的最佳沉积温度。     

氧分压对室温制备掺铝氧化锌薄膜性能的影响

室温下,采用脉冲直流反应磁控溅射方法在玻璃衬底上制备了掺铝的氧化锌(ZnO:Al,AZO)透明导电薄膜。采用配有λ-sensor氧分压传感器的控制器闭环控制氧分压,研究了氧分压对薄膜结构、表面形貌和光电性能的影响。结果表明:在不同的氧分压下制备的AZO薄膜均为多晶纤锌矿结构,具有[002]择优取向,其晶体呈柱状生长,晶粒之间结合紧密。氧分压为3.36×10–2Pa时,AZO薄膜的性能指数最高,其电阻率为1.15×10–3·cm,相应的载流子浓度为2.1×1020/cm3,载流子迁移率为25.8cm2/(V s),可见光透射率为79.1%。随着AZO薄膜的载流子浓度由1.03×1020cm–3增加到3.64×1020cm–3,薄膜禁带宽度由3.49eV增大到3.72eV。     

双靶磁控溅射透明导电氧化铟锡锆薄膜及其性能

利用ITO(InSnO)靶和金属Zr靶,采用磁控溅射法在玻璃衬底上制备了ITO和ITZO(InSnZrO)薄膜。高价金属元素Zr的掺杂导致了薄膜向(400)晶面择优取向转变,促使ITO薄膜具有更好的晶化程度、较低的表面粗糙度和更好的光电性能。根据处于特定介质环境中ITO和ITZO薄膜的相对电阻变化(△R/R),ITZO薄膜显示了比ITO薄膜更好的化学和热稳定性。通过盐酸腐蚀前后的扫描电镜和X射线光电子能谱仪测试表明,Zr的加入提高了薄膜的稳定性,降低了氯离子穿透氧化层的能力,提高了氧化层的结构稳定性,大大降低了薄膜发生点蚀的概率。薄膜在0.1 mol/L盐酸中的极化曲线表明,ITZO薄膜发生了自钝化现象,显示了较好的耐腐蚀性能。除了晶体结构的影响之外,稳定性较好的氧化锆也提高了薄膜的化学稳定性和热稳定性。     

平面磁控溅射氧化锌（ZnO）薄膜的几个问题

Ｃ轴取向一致的氧化锌（ＺｎＯ）薄膜是一种良好的压电材料。采用平面磁控溅射是制备ＺｎＯ薄膜较为理想的一种方法。为讨论溅射用靶体的掺杂、溅射功率和基片温度等问题，本实验溅射使用掺有２￣５ｗｔ％碳酸锂（Ｌｉ２ＣＯ３）的烧结陶瓷靶；溅射功率６００Ｗ左右；沉积薄膜基片温度３００℃，并注意其他有关条件的调节，对获得的薄膜用ＸＲＤ等方法评价性能。     

Structural Modification of TiO2 Nanorod Films with an Influence on the Photovoltaic Efficiency of a Dye-Sensitized Solar Cell (DSSC)

TiO₂ nanorod films have been deposited on ITO substrates by dc reactive magnetron sputtering technique. The structures of these nanorod films were modified by the variation of the oxygen pressure during the sputtering process. Although all these TiO₂ nanorod films deposited at different oxygen pressures show an anatase structure, the orientation of the nanorod films varies with the oxygen pressure. Only a very weak (101) diffraction peak can be observed for the TiO₂ nanorod film prepared at low oxygen pressure. However, as the oxygen pressure is increased, the (220) diffraction peak appears and the intensity of this diffraction peak is increased with the oxygen pressure. The results of the SEM show that these TiO₂ nanorods are perpendicular to the ITO substrate. At low oxygen pressure, these sputtered TiO₂ nanorods stick together and have a dense structure. As the oxygen pressure is increased, these sputtered TiO₂ nanorods get separated gradually and have a porous structure. The optical transmittance of these TiO₂ nanorod films has been measured and then fitted by OJL model. The porosities of the TiO₂ nanorod films have been calculated. The TiO₂ nanorod film prepared at high oxygen pressure shows a high porosity. The dye-sensitized solar cells (DSSCs) have been assembled using these TiO₂ nanorod films prepared at different oxygen pressures as photoelectrode. The optimum performance was achieved for the DSSC using the TiO₂ nanorod film with the highest (220) diffraction peak and the highest porosity.     

在ITO玻璃衬底上制备锆钛酸铅铁电薄膜

利用射频反应性溅射沉积技术在掺的Ｓｎ的Ｉｎ２Ｏ３导电透明膜衬底上制备了钙钛矿型Ｐｂ（Ｚｒ,Ｔｉ）Ｏ３（ＰＺＴ）铁电薄膜。研究了沉积参量与热处理工艺对铁电薄膜结构和性能的影响。运用Ｘ射线衍射、Ｘ射线光电子能谱和扫描电镜等技术,分析了薄膜的晶体结构、表面形貌和表面元素化学状态。测量了不同处理条件下薄膜的铁电性能。结果表明：在掺Ｓｎ的Ｉｎ２Ｏ３导电透明膜衬底上可以得到表面无裂纹,化学计量比符合要求的ＰＺ     

Spontaneously ordered TiO2 nanostructures

Titanium dioxide thin films were deposited on quartz substrates kept at different O₂ pressures using pulsed laser deposition technique. The effects of reactive atmosphere and annealing temperature on the structural, morphological, electrical and optical properties of the films are discussed. Growth of films with morphology consisting of spontaneously ordered nanostructures is reported. The films growth under an oxygen partial pressure of 3 × 10⁻⁴ Pa consist in nanoislands with voids in between them whereas the film growth under an oxygen partial pressure of 1 × 10⁻⁴ Pa, after having being subjected to annealing at 500 °C, consists in nanosized elongated grains uniformly distributed all over the surface. The growth of nanocrystallites with the increase in annealing temperature is explained on the basis of the critical nuclei-size model.     

Transparent and conductive indium tin oxide/polyimide films prepared by high‐temperature radio‐frequency magnetron sputtering

A highly transparent and thermally stable polyimide (PI) substrate was prepared and used for the fabrication of indium tin oxide (ITO)/PI films via radio‐frequency magnetron sputtering at an elevated substrate temperature. The effect of the deposition conditions, that is, the oxygen flow rate, substrate temperature, sputtering power, and working pressure, on the optical and electrical properties of the ITO/PI films were investigated from the microstructural aspects. The results indicate that the optical and electrical properties of ITO were sensitive to the oxygen. Moreover, it was beneficial to the improvement of the ITO conductivity through the adoption of a high substrate temperature and sputtering power and a low working pressure in the deposition process. A two‐step deposition method was developed in which a thick bulk ITO layer was overlapped by deposition on a thin seed ITO layer with a dense surface to prepare the highly transparent and conductive ITO/PI films. The ITO/PI film after annealing at 240°C gave a transmittance of 83% and a sheet resistance of 19.7 Ω/square. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42753.     

Impact of oxygen partial pressure on resistive switching characteristics of PLD deposited ZnFe2O4 thin films for RRAM devices

In this paper we show resistive switching characteristics of ZnFe₂O₄ thin films grown by pulsed laser deposition at various oxygen partial pressures. We discuss how the microstructure, surface roughness, oxidation condition, and resistive switching properties of ZnFe₂O₄ thin films are influenced by the oxygen partial pressure prevalent in the chamber during the deposition process. The films were deposited at oxygen partial pressure (pO₂) of 0.0013, 0.013, 0.13 and 1.3 mbar. The ZnFe₂O₄ thin film deposited at the lowest pO₂ (0.0013 mbar) did not display a resistive switching characteristic. The ZnFe₂O₄ device deposited at 0.13 mbar yielded the best results. These devices have a low SET variance and a large memory window (more than 2 orders of magnitude) due to an optimum amount of oxygen vacancies/ions contained in the ZnFe₂O₄ film, which is helpful for better resistive switching, than devices deposited at other oxygen pressures. We also find that the migration of oxygen vacancies is linked to the resistive switching process.     

Mechanical performance of ITO/Ag/ITO multilayer films deposited on glass substrate by RF and DC magnetron sputtering

ITO/Ag/ITO multilayer thin films have been a potential substitute of the conventional single-layer transparent conducting film. Nevertheless, the mechanical stability under preparation and in-service conditions still limits their applications and developments. In this paper, the influences of different structural properties as well as layer structure on both surface morphological properties and mechanical properties of the ITO/Ag/ITO multilayer thin films in comparison with commercial single-layer ITO thin film were systematically investigated. The results demonstrate that, i) the tri-layer composite has large impacts on the preferential orientation, and exhibits the decreased values of surface roughness, net lattice distortion and residual stress; ii) the increased hardness (H) and decreased Young's modulus (E) for full annealed ITO/Ag/ITO multilayer films indicate that it is possible to tailor mechanical properties of the materials by manufacturing multilayer composite; iii) the ITO/Ag/ITO multilayer thin film exhibits remarkable improvements in wear resistance with the increase of annealing temperature, which is mainly attributed to the increased ratios of H/E and H³/E².     

Characterization of indium tin oxide (ITO) thin films prepared by a sol-gel spin coating process

Indium tin oxide (ITO) thin films were prepared by a sol-gel spin coating method, fired, and then annealed in the temperature range of 450-600°. The XRD patterns of the thin films indicated the main peak of the (2 2 2) plane and showed a higher degree of crystallinity with an increase in the annealing temperature. Upon annealing the films at 500 and 600°, two binding energy levels of Sn⁴⁺ ion of 486.9 eV and 486.6 eV, respectively, were measured in the XPS spectra. The ITO film that was annealed at 600° contained two oxidation states of Sn, Sn²⁺ and Sn⁴⁺, and it had a higher sheet resistance based on a rather low doping concentration of Sn⁴⁺. The film that was annealed at 500° and subsequently treated with 0.1 N HCl solution for 40 s showed a sheet resistance of 225 Ω/square. The surface treatment by the acidic solution diminished the RMS (root mean square) roughness value and the residual carbon content (XPS peak intensity of carbon) of the ITO films. It seems that the acid-cleaning of the ITO thin films led to a decrease of the surface roughness and sheet resistance.     

Single step electrosynthesis of Cu2ZnSnS4 (CZTS) thin films for solar cell application

The Cu₂ZnSnS₄ (CZTS) thin films have been electrodeposited onto the Mo coated and ITO glass substrates, in potentiostatic mode at room temperature. The deposition mechanism of the CZTS thin film has been studied using electrochemical techniques like cyclic voltammetery. For the synthesis of these CZTS films, tri-sodium citrate and tartaric acid were used as complexing agents in precursor solution. The structural, morphological, compositional, and optical properties of the CZTS thin films have been studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), EDAX and optical absorption techniques respectively. These properties are found to be strongly dependent on the post-annealing treatment. The polycrystalline CZTS thin films with kieserite crystal structure have been obtained after annealing as-deposited thin films at 550 in Ar atmosphere for 1 h. The electrosynthesized CZTS film exhibits a quite smooth, uniform and dense topography. EDAX study reveals that the deposited thin films are nearly stoichiometric. The direct band gap energy for the CZTS thin films is found to be about 1.50 eV. The photoelectrochemical (PEC) characterization showed that the annealed CZTS thin films are photoactive.     

Growth and characterization of highly oriented CuBr thin films through room temperature electrochemical route

A simple electrochemical process has been demonstrated to grow highly oriented copper(I) bromide thin films on indium-doped tin oxide (ITO) glass through reducing CuBr₂ in aqueous solutions at room temperature. The copper(I) bromide thin films grow preferential orientation along the 〈1 1 1〉 crystal axis from the X-ray diffraction patterns. The orientation growth of the CuBr thin films is little affected by the solution pH and applied potentials. The possible mechanism of the orientation growth has been discussed, and the surface energy of different crystal plane of CuBr crystal is believed to play an important role to control the orientation growth of the CuBr thin films. The oriented films exhibit intense free-exciton photoluminescence at room temperature.     

Advanced indium-tin oxide ceramics for sputtering targets

Indium-tin oxide (ITO) ceramic sputtering targets are widely used in formation of electrically conductive transparent thin films for electrodes in flat panel displays, solar cells, antistatic films and others, and which are commonly produced by a conventional dc magnetron sputtering process. The ceramic targets should be of high purity with a uniform microcrystalline structure and should possess high density and high electrical conductivity. In the present work, the challenges of the ceramic composition (e.g. the ratio of In₂O₃ and SnO₂) and manufacturing are considered; they include the use of high quality starting materials, particularly In₂O₃ powders with respect to purity, morphology and sinterability, manufacturing routes and sintering process. Positive experience in the development and manufacturing of ITO ceramic planar sputtering targets using in-house prepared In₂O₃ powders is reported. ITO ceramic tiles with areas up to 1500–1700 cm² and densities of 99+% of TD are manufactured. Physical properties of the ITO ceramics and sputtered films have been studied.