磁控溅射TiAlVN薄膜中V含量对其结构和抗腐蚀性能的影响

向TiAlN薄膜中添加V可改善薄膜性能.采用磁控溅射技术沉积了不同V含量的TiAlVN薄膜,通过能谱仪、台阶仪、X射线衍射仪(XRD)和原子力显微镜(AFM)分析薄膜的成分、厚度、相结构和表面形貌,用动电位极化的方法研究薄膜的抗腐蚀性能.结果表明:TiAlVN薄膜属于面心立方(fcc)和六方密排(hcp)二重结构,晶格...     

衬底负偏压对溅射Ta2O5薄膜晶化温度及介电性能的影响

采用磁控溅射法，在衬底温度为620℃时，通过引入合适的衬底负偏压(100—200V)，获得了结晶良好的Ta2O5薄膜．衬底负偏压增强了正离子对衬底表面的轰击作用，加速了其在衬底表面的松弛扩散效应，从而降低了Ta2O5薄膜的晶化温度，改善了其结晶性．同时，G—V测试结果表明：衬底负偏压进一步改善了Ta2O5薄膜的介电性能．     

导电玻片上氧化亚铜膜的电沉积和表征

研究了用简单铜盐通过阴极还原氧化亚铜的电化学行为，讨论了一些工艺因素对在导电玻片上电沉积Cu2O薄膜的影响，并对所制备的Cu2O薄膜分别用台阶仪、X射线衍射仪(XRD)、扫描电镜(SEM)、X射线光电子能谱(XPS)进行表征．得到的较佳工艺条件为：电势-0．22～-0．45V(vs SCE)，温度为60℃，pH值为5．5～6．0，(CH3COO)2Cu浓度为0．015—0．04mol／L．表征结果发现，随池温的升高，晶粒尺寸从0.2μm增加到0．4μm，60。C沉积的Cu2O薄膜开始具有(111)面择优取向，Cu2O膜纯度高，薄膜表面呈网络多孔结构     

空心阴极制备α—CNx：H薄膜的结构及力学性能研究

以CH4和N2为反应气体，采用空心阴极放电激发的等离子体增强化学气相沉积法在Si片上制备出了氢化非晶碳氮（α—CNx：H）薄膜。利用原子力显微镜（AFM）对薄膜的表面光洁度及表面形貌进行了测量和表征。利用X射线光电子能谱（XPS）、傅立叶红外吸收谱（FTIR）和纳米压入（nano—indentation）等测试手段分析了薄膜的成分、结构及力学性能。结果表明：薄膜的表面光滑、致密，表面光洁度〈1nm。薄膜的最大N含量达到了26．39％（原子分数），对应的N／C为0．41。XPS和FTIR分析表明：薄膜中的C、N原子是通过C—N、C=N、C≡N结合的，同时存在一定量的-CHx和-NHx基团。另外，我们发现薄膜的硬度及弹性模量随N2／CH4比的增加而增加，并且主要受微观结构（C—N／C≡N比）的影响。     

以聚苯乙烯为绝缘层的C（60）场效应晶体管

研究制备了以聚苯乙烯(polystyrene)作为绝缘层,富勒烯C60为半导体有源层的一种全有机n型场效应晶体管.利用原子力显微镜(AFM)分析了聚苯乙烯薄膜及其表面C60薄膜的形貌.电学特性测试结果表明器件性能优良,场效应电子迁移率达到1.05cm2/V·s,开关比为9.4×105.     

五氧化二钽薄膜的制备及其I—U特性

本文利用脉冲直流反应磁控溅射的方法制备了五氧化二钽(Ta205)薄膜，俄歇电子能谱仪测试了薄膜的成分含量，椭偏仪测试了Ta205薄膜的厚度和折射率，XRD分析了薄膜的晶体结构，并且分别研究了氧气含量、基底温度等成膜工艺对薄膜的影响。研究结果表明薄膜的成分主要是由氧气含量决定的。利用金属—绝缘体(介质膜)—金属(MIM)结构初步对Ta2O5薄膜进行了电学性能的测试：皮安电流电压源测试了薄膜的I—U特性，制备出的薄膜折射率在2．1-2．2，MIM的I—U特性曲线显示了较好的对称性和低的漏电流密度。     

基片温度对强流脉冲离子束烧蚀等离子体沉积类金刚石薄膜结构和性能的影响

利用强流脉冲离子柬(High-intensity pulsed ion beam-HIPIB)烧蚀等离子体技术在Si(100)基体上沉积类金刚石(Diamond-like carbon-DLC)薄膜，基片温度的变化范围从25℃(室温)到400℃。利用Raman谱、X射线光电子谱(XPS)、X射线衍射(XRD)和原子力显微镜(AFM)研究基片温度对DLC薄膜的化学结合状态、表面粗糙度、薄膜显微硬度和薄膜内应力的影响。根据XPS和Raman谱分析得出，基片温度低于300℃时，sp3C杂化键的含量大约在40％左右；从300℃开始发生sp3C向sp2C的石墨化转变。随着沉积薄膜时基片温度的提高，DLC薄膜中sp3C的含量降低，由25℃时42．5％降到400℃时8．1％，XRD和AFM分析得出，随着基片温度的增加，DLC薄膜的表面粗糙度增大，薄膜的纳米显微硬度降低，摩擦系数提高，内应力降低。基片温度为100℃时沉积的DLC薄膜的综合性能最好，纳米显微硬度22GPa，表面粗糙度为0．75nm，摩擦系数为0．110。     

溶胶凝胶制备Bi_4Ti_3O_(12)铁电薄膜及性能研究

研究了sol-gel法制备Bi_4Ti_3O_(12)铁电薄膜和该薄膜的电学性质、光学性质,以及Bi_4Ti_3O_(12)晶体的热力学唯象理论。主要内容如下:①以正丁醇钛和硝酸铋为原料,合成了稳定均匀的Bi-Ti溶胶和凝胶。研究了乙醇胺的催化作用机理和前驱体溶液的水解、聚合反应机理。发现乙醇胺与Bi~(3+)离子的络合反应阻止Bi离子的水解。研究了干凝胶的晶化过程,发现干凝胶在晶化过程中有三个中间相存在。②分别在Pt/Ti/Si、Si、Y-ZrO_2、SrTiO_3(100)和石英玻璃基片上生长出c轴取向的Bi_4Ti_3O_(12)薄膜。薄膜的取向程度受到衬底表面结构和Bi_4Ti_3O_(12)晶体的晶面能的制约。前驱体溶液的酸碱度对薄膜的结晶性有较大影响。③研究了Bi_4Ti_3O_(12)/n-Si薄膜的C—V特性,从理论上分别推导出理想的和有载流子注入的MFS结构的C—V曲线的回滞方向。④研究了c轴取向Bi_4Ti_3O_(12)纳米薄膜的光学吸收性能和量子尺寸效应引起的光能隙漂移现象。薄膜的能隙宽度强烈依赖于薄膜的晶粒大小。⑤用Landau-Ginsburg-Devonshire形式系统地研究了在应力条件下Bi_4Ti_3O_(12)的铁电性质、介电性质和压电性质,以及在应力诱导下的Bi_4Ti_3O_(12)居里温度的漂移现象。     

非平衡磁控溅射氮化钛薄膜及其性能研究

采用非平衡磁控溅射技术,在钛合金(Ti6Al4V)表面沉积氮化钛薄膜。通过改变氮气和氩气分压比(PN/PAr)和基体偏压,制备出不同结构、性能的氮化钛薄膜。采用X射线衍射技术、原子力显微镜、PS-168型电化学测量系统、CSEM球盘摩擦磨损实验机、HXD-1000 knoop显微硬度仪等研究了薄膜的结构、表面形貌、耐腐蚀性能与机械性能。结果表明,采用非平衡磁控溅射技术制备出了致密的氮化钛薄膜。当PN/PAr较小时,氮化钛薄膜中存在Ti2N时,Ti2N相可以有效提高薄膜的硬度和耐磨损性能;当PN/PAr增加到0.1时,薄膜硬度达到最大,耐磨损性能最优;随着PN/PAr的继续增大,氮化钛薄膜中主要存在TiN相,氮化钛薄膜的复合硬度和耐磨损性能降低。在钛合金(Ti6Al4V)表面沉积氮化钛薄膜可以显著提高其在Hanks类体液中的耐腐蚀性能。     

V_2O_5-TiO_2离子存储电极薄膜的溶胶-凝胶法制备与性能研究

利用无机溶胶-凝胶技术制备了V2O5-(TiO2)x离子存储电极薄膜。采用X射线衍射(XRD)、原子力显微镜(AFM)、Raman光谱、循环伏安法(CV)和紫外-可见光透射光谱分别研究了复合薄膜的微观结构、化学计量、锂离子注入性能以及光学性能。结果表明复合薄膜具有V2O5的层状结构,其c轴方向的结构取向性有所降低;颗粒尺寸和表面粗糙度显著减小;同时TiO2的复合导致薄膜中V2O5的化学计量发生偏移,氧空位数量增多。当x=0.2时,薄膜具有相对较高的离子存储容量及循环稳定性,并且在离子注入/脱出状态均获得相当高的可见光透过性。     

Highly conductive and porous activated reduced graphene oxide films for high-power supercapacitors

We present a novel method to prepare highly conductive, free-standing, and flexible porous carbon thin films by chemical activation of reduced graphene oxide paper. These flexible carbon thin films possess a very high specific surface area of 2400 m(2) g(-1) with a high in-plane electrical conductivity of 5880 S m(-1). This is the highest specific surface area for a free-standing carbon film reported to date. A two-electrode supercapacitor using these carbon films as electrodes demonstrated an excellent high-frequency response, an extremely low equivalent series resistance on the order of 0.1 ohm, and a high-power delivery of about 500 kW kg(-1). While higher frequency and power values for graphene materials have been reported, these are the highest values achieved while simultaneously maintaining excellent specific capacitances and energy densities of 120 F g(-1) and 26 W h kg(-1), respectively. In addition, these free-standing thin films provide a route to simplify the electrode-manufacturing process by eliminating conducting additives and binders. The synthetic process is also compatible with existing industrial level KOH activation processes and roll-to-roll thin-film fabrication technologies.     

Zinc oxide epitaxial thin film deposited over carbon on various substrate by pulsed laser deposition technique

Zinc Oxide (ZnO) is a promising candidate material for optical and electronic devices due to its direct wide band gap (3.37 eV) and high exciton binding energy (60 meV). For applications in various fields such as light emitting diode (LED) and laser diodes, growth of p-type ZnO is a prerequisite. ZnO is an intrinsically n-type semiconductor. In this paper we report on the synthesis of Zinc Oxide-Carbon (ZnO:C) thin films using pulsed laser deposition technique (PLD). The deposition parameters were optimized to obtain high quality epitaxial ZnO films over a carbon layer. The structural and optical properties were studied by glazing index X-ray diffraction (GIXRD), photoluminescence (PL), optical absorption (OA), and Raman spectroscopy. Rutherford backscattering spectroscopy (RBS), scanning electron microscopy with energy dispersive spectroscopy (SEMEDS) and atomic force microscopy (AFM) were employed to determine the composition and surface morphology of these thin films. The GIXRD pattern of the synthesized films exhibited hexagonal wurtzite crystal structure with a preferred (002) orientation. PL spectroscopy results showed that the emission intensity was maximum at -380 nm at a deposition temperature of 573 K. In the Raman spectra, the E2 phonon frequency around at 438 cm(-1) is a characteristic peak of the wurtzite lattice and could be seen in all samples. Furthermore, the optical direct band gap of ZnO films was found to be in the visible region. The growth of the epitaxial layer is discussed in the light of carbon atoms from the buffer layer. Our work demonstrates that the carbon is a novel dopant in the group of doped ZnO semiconductor materials. The introduction of carbon impurities enhanced the visible emission of red-green luminescence. It is concluded that the carbon impurities promote the zinc related native defect in ZnO.     

Improved electrochemical performance of nitrocarburised stainless steel by hydrogenated amorphous carbon thin films for bone tissue engineering

In this study, hydrogenated amorphous carbon thin films, structurally similar to diamond‐like carbon (DLC), were deposited on the surface of untreated and plasma nitrocarburised (Nitrocarburizing‐treated) stainless steel medical implants using a plasma‐enhanced chemical vapour deposition method. The deposited DLC thin films on the nitrocarburising‐treated implants (CN+DLC) exhibited an appropriate adhesion to the substrates. The results clearly indicated that the applied DLC thin films showed excellent pitting and corrosion resistance with no considerable damage on the surface in comparison with the other samples. The CN+DLC thin films could be considered as an efficient approach for improving the biocompatibility and chemical inertness of metallic implants.Inspec keywords: tissue engineering, bone, biomedical materials, electrochemistry, amorphous state, carbon, hydrogen, thin films, plasma CVD, adhesion, corrosion resistance, surface hardeningOther keywords: electrochemical performance, plasma nitrocarburised stainless steel medical implants, hydrogenated amorphous carbon thin films, bone tissue engineering, plasma‐enhanced chemical vapour deposition method, adhesion, corrosion resistance, biocompatibility, chemical inertness, metallic implants, C:H     

Slip‐rolling resistance of ta‐C and a‐C coatings up to 3,000 MPa of maximum Hertzian contact pressure

The slip‐rolling resistances of hard and stiff thin films under high Hertzian contact pressures can be improved by optimizing the “coating/substrate systems”. It is known from former investigations that the so‐called “egg‐shell” effect is no general hindrance for high slip‐rolling resistance of thin hard coatings. The coating stability depends more on specific deposition process and coating/substrate interface design. In this article it is experimentally shown, that pure amorphous carbon thin films with hardness between 15 and 63 GPa can be slip‐rolling resistant several million load cycles under a maximum Hertzian contact pressures of up to 3.0 GPa. Whereas all coatings were stable up to 10 million load cycles in paraffin oil at room temperature, reduced coating lifetime was found in SAE 0W‐30 engine oil at 120°C. It was shown how the coating hardness and the initial coating surface roughness influence the running‐in process and coating lifetime. No clear correlation between coating hardness and coating lifetime could be observed, but friction coefficients seem to be reduced with higher coating hardness. Very low friction down to ?0.03 in unmodified engine oils was found for the hardest ta‐C film.     

Tribologisches Verhalten von harten und superharten Kohlenstoffschichten

Tribological behavior of superhard amorphous carbon films The tribological behaviour of amorphous carbon films is determined by monomolecular covering layers strongly attached to the surface. They cause the very low friction in normal humid air, their absence in dry air or vacuum leads to high friction. Any lubricants usually do not improve the tribological behaviour in comparison to air. However for non‐hydrogenated ta‐C films by attachment of specially adapted lubricants an additionally marked reduction of friction is possible.     

Nano-polycrystalline vanadium oxide thin films prepared by pulsed laser deposition

Nano-polycrystalline vanadium oxide thin films have been successfully produced by pulsed laser deposition on Si(100) substrates using a pure vanadium target in an oxygen atmosphere. The vanadium oxide thin film is amorphous when deposited at relatively low substrate temperature (500 degrees C) and enhancing substrate temperature (600-800 degrees C) appears to be efficient in crystallizing VOx thin films. Nano-polycrystalline V3O7 thin film has been achieved when deposited at oxygen pressure of 8 Pa and substrate temperature of 600 degrees C. Nano-polycrystalline VO2 thin films with a preferred (011) orientation have been obtained when deposited at oxygen pressure of 0.8 Pa and substrate temperatures of 600-800 degrees C. The vanadium oxide thin films deposited at high oxygen pressure (8 Pa) reveal a mix-valence of V5+ and V4+, while the VOx thin films deposited at low oxygen pressure (0.8 Pa) display a valence of V4+. The nano-polycrystalline vanadium oxide thin films prepared by pulsed laser deposition have smooth surface with high qualities of mean crystallite size ranging from 30 to 230 nm and Ra ranging from 1.5 to 22.2 nm. Relative low substrate temperature and oxygen pressure are benifit to aquire nano-polycrystalline VOx thin films with small grain size and low surface roughness.     

Abscheidung superharter Kohlenstoffschichten mittels Laser‐Arco® auf dem Weg vom Labor in die industrielle Serienfertigung

Superhard carbon film deposition by means of Laser‐Arco® on the way from the Laboratory into the industrial series coating Diamond‐like carbon films (DLC) are more and more applied as wear protection coatings for components and tools due to their unique combination of high hardness, low friction and sticking tendency to metallic counter bodies. Up to now applied DLC films are hydrogen containing (a‐C:H) or metal carbon films (Me‐C:H) deposited by a plasma assisted CVD process from carbon‐hydrogen gas mixtures. Their wide industrial effort results from that the can be deposited with slowly modified coating machines for classical hard coating (e.g. TiN or CrN). A new generation DLC films are the hydrogen‐free ta‐C films (ta‐C = tetrahedral bounded amorphous carbon) with a between two and three‐times higher hardness and with a resulting higher wear resistance under extreme condition than classical DLC films. They have excellent emergency running properties at lubrication break down. Their industrial application is more difficult due to that they cannot deposited with modified coating machines for classical hard and DLC coating and a new technology with corresponding equipment was not available up to now. The laser controlled, pulsed arc deposition technology (Laser‐Arco®) of the Fraunhofer IWS Dresden has this potential. In kind of a Laser‐Arc‐Module‐source the ta‐C film deposition can be integrated in every industrial used deposition machine.     

Diamantartige Kohlenstoffschichten steigern die Effizienz

Diamond‐like carbon thin films enhance efficiency — laser arc deposition of ta‐C Rising prices for fossil fuels as well as the increasing effects of the climate change due to the emission of greenhouse gases reveal the necessity of saving energy. Low friction coatings have an enormous potential in saving energy. Carbon based coatings — named as DLC coatings — are especially well suited for low friction coatings. In particular hydrogen‐free tetrahedral amorphous carbon (ta‐C) coatings are of great interest due to their extraordinary low wear properties. In addition they show excellent low friction properties and especially in combination with specific lubricants the so‐called super low friction effect. For the deposition of ta‐C coatings PVD methods have to be applied instead of CVD methods as it is the case for conventional DLC coatings. We have developed a deposition method which is based on a pulsed arc steered by a laser (Laser‐Arc). This allows us to use large cathodes resulting in a high long‐term stability. Furthermore, the carbon plasma source can be combined with a filtering unit removing almost all droplets and particles, which usually are characteristic for an arc process. The resulting Laser‐Arc source allows for the deposition of smooth and virtually defect‐free ta‐C coatings with a competitive deposition rate.     

Preparation, characterization and anion exchange properties of polypyrrole/carbon nanotube nanocomposites

In this study, polypyrrole (PPy) thin films were electrodeposited on carbon nanotube (CNT) backbones by applying a constant deposition potential in 0.1 M pyrrole solution with different electrolytes, such as NaCl, NaNO3, or NaClO4. The hybrid films were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy, and cyclic voltammetry. SEM images revealed the nanostructrure of PPy films generated on CNT surface. The electrochemical and anion exchange properties of the PPy-CNT composite films have been investigated. Nanostructured composite thin films of PPy-CNTs were studied by cyclic voltammetry between 0.4 and -0.8 V in aqueous solution to evaluate their cycling stability and capacity for electrically switched anion exchange. The presence of the CNT backbone greatly improved the anion exchange capacity and stability of the PPy-CNT composite film, which may be attributed to the high surface area of CNT matrix, nanostructure of the PPy film, and the interaction between CNTs and PPy.     

氧等离子体处理对氧化铟锡表面化学状态影响的ADXPS研究

利用变角X射线光电子谱对氧等离子体处理前后氧化铟锡ITO薄膜的表面化学状态进行了表征.实验发现用溶剂清洗之后的ITO薄膜表面存在一层厚度大约为0.7nm的非导电碳氢化合物污染层.氧等离子体处理方法可有效地消除C污染,而残存的少量污染C被部分氧化形成含羰基和羧基的化学物种.氧等离子体处理不仅提高了约5.0nm深度范围内的ITO薄膜表层中O的总体含量,更重要的是提高了膜层中O2-离子氧种的含量,改变了膜层化学结构,使得ITO薄膜表面的导电性能降低,同时改善了整个表面层化学结构的均匀性.