铜在磷酸溶液中的电化学抛光研究

通过阳极极化和电化学阻抗谱测试,研究了铜在磷酸溶液中进行电化学抛光的电化学行为。研究发现:随着磷酸浓度的增加,铜在0.2,0.4,0.6,0.8 V四个电位下电化学抛光后的粗糙度都呈现先减小、后增大的趋势,在磷酸质量分数为55%时达最低值;EIS图谱拟合的Rs值的变化反映了磷酸盐粘膜层电阻和铜表面氧化膜电阻的变化,此外,随着磷酸浓度的增加,EIS中第一个容抗半圆的弛豫时间延长,铜的溶解反应速度加快。     

电化学机械复合抛光不锈钢板

设计了电化学机械复合抛光装置、工具，研究了加工电压、磨轮压力与加工速度的关系，加工电压对表面粗糙度的影响。     

电化学抛光在模具上的应用

本文测定了电化学抛光的各项技术参数 ,表明能明显减小金属制件的表面粗糙度 ,将Ra值减至 0 .16μm以下 ,达到镜面光洁度。将此工艺用于注塑模具 ,使难以用机械方法抛光的复杂表面明显光亮。从而 ,将使其制成的塑料产品增强销售竞争力。     

高温合金脉冲电化学复合抛光实验研究

电化学机械复合抛光是近年来发展起来的一种抛光新技术。针对粗糙表面的高效抛光问题,提出一种两阶段的电化学机械复合抛光和纯机械抛光相结合的方法。论述了脉冲电化学机械复合抛光加工的实验设备,进行了系统的工艺参数实验研究;用方差分析的方法分析了各参数对加工试件表面粗糙度影响的显著性,得出最佳的工艺参数;详细分析了不同磨头加工时各参数对表面粗糙度的影响规律。实验研究表明,利用脉冲电化学机械复合抛光的加工方法,采用各种类型的阴极工具头,可实现镜面加工。     

脉冲电化学光整加工在模具镜面抛光中的应用

综述了脉冲电化学在金属材料光整加工领域中的研究情况,介绍了脉冲电化学的加工优势,分析了脉冲电化学光整加工的工作机理、加工工艺、实验研究以及应用状况,指出了脉冲电化学及其复合加工工艺在实现模具镜面抛光应用中的可行性和现实性。     

电化学抛光技术新进展

随着材料加工不断地向精密化方向发展, 传统抛光技术很难达到高精度的表面抛光要求.作为新型抛光技术一个很重要的分支, 电化学抛光以其加工效率高、工件无损耗、表面光滑、无内应力、不受材料硬度的限制等优点,在表面抛光领域中得到快速的发展.简要介绍了电化学抛光的原理和特点,总结了影响电化学抛光效果的主要因素,综述了电化学抛光技术的新进展.     

超声波--电化学抛光技术在模具中的应用

本文详细阐述了超声波—电化学抛光技术的机理、装置、加工特点和应用范围，从而提出了模具型腔面抛光的新途径。     

不锈钢表面的电化学机械复合抛光

介绍了一台由立式铣床改装的电化学机械复合抛光装置。讨论了加工电压、磨轮压力与加工效率的关系以及加工电压对表面粗糙度的影响。     

大型工件的电化学抛光工艺

通过城市公交车候车亭的大型工件整体电化学抛光实践，介绍了大型工件电化学抛光的特点及工艺方案。     

Growth of HT-LiCoO2 thin films on Pt-metalized silicon substrates

Layered LiCoO2 (HT-LiCoO2) films were grown on Pt-metalized silicon (PMS) substrates and polished bulk nickel (PBN) substrates by pulsed laser deposition. The effects of substrate temperature, oxygen pressure, and substrate surface roughness on the microstructure of LiCoO2 films were investigated. It has been found that a higher substrate temperature and a higher oxygen pressure favor the formation of better crystallized and less lithium-deficient HT-LiCoO2 films. The HT-LiCoO2 film deposited on PBN substrates consists of large randomly orientated equiaxial grains, whereas on PMS substrate, it is made up of loosely packed highly [001] preferential orientated triangular shaped grains with the average grain size less than 100nm. Electrochemical measurements show that the highly [001] preferentially orientated nanostructured HT-LiCoO2 thin film grown on PMS substrate has good structural stability upon lithium insertion/extraction and can deliver an initial discharge capacity of approximately 45 μA·h·cm-2μm-1 with a cycling efficiency of above 99% at the charge/discharge rate of 0.5C.     

Growth of HT-LiCoO2 thin films on Pt-metalized silicon substrates

Layered LiCoO2 （HT-LiCoO2） films were grown on Pt-metalized silicon （PMS） substrates and polished bulk nickel （PBN） substrates by pulsed laser deposition. The effects of substrate temperature, oxygen pressure, and substrate surface roughness on the microstructure of LiCoO2 films were investigated. It has been found that a higher substrate temperature and a higher oxygen pressure favor the formation of better crystallized and less lithium-deficient HT-LiCoO2 films. The HT-LiCoO2 film deposited on PBN substrates consists of large randomly orientated equiaxial grains, whereas on PMS substrate, it is made up of loosely packed highly [001] preferential orientated triangular shaped grains with the average grain size less than 100 nm. Electrochemical measurements show that the highly [001] preferentially orientated nanostructured HT-LiCoO2 thin film grown on PMS substrate has good structural stability upon lithium insertion/extraction and can deliver an initial discharge capacity of approximately 45μA·h·cm^-2·μm^-1 with a cycling efficiency of above 99% at the charge/discharge rate of 0.5 C.     

Transparent p-type CuxS thin films

The effect of different mild post-annealing treatments in air, at 270 °C, for 4-6 min, on the optical, electrical, structural and chemical properties of copper sulphide (Cu_xS) thin films deposited at room temperature are investigated. Cu_xS films, 70 nm thick, are deposited on glass substrates by vacuum thermal evaporation from a Cu₂S:S (50:50 wt.%) sulphur rich powder mixture. The as-deposited highly conductive crystalline CuS (covellite) films show high carrier concentration (∼10²² cm⁻³), low electrical resistivity (∼10⁻⁴ Ω cm) and inconclusive p-type conduction. After the mild post-annealing, these films display increasing values of resistivity (∼10⁻³ to ∼10⁻² Ω cm) with annealing time and exhibit conclusive p-type conduction. An increase of copper content in Cu_xS phases towards the semiconductive Cu₂S (chalcocite) compound with annealing time is reported, due to re-evaporation of sulphur from the films. However, the latter stoichiometry was not obtained, which indicates the presence of vacancies in the Cu lattice. In the most resistive films a Cu₂O phase is also observed, diminishing the amount of available copper to combine with sulphur, and therefore the highest values of optical transmittance are reached (65%). The appearance on the surface of amorphous sulphates with annealing time increase is also detected as a consequence of sulphur oxidation and replacement of sulphur with oxygen. All annealed films are copper deficient in regards to the stoichiometric Cu₂S and exhibit stable p-type conductivity.     

Co和Cu薄膜电学特性和连续性特征的判据

采用离子束溅射沉积了不同厚度的Co膜和Cu膜,利用四电极法测量了薄膜的电阻率,从而得到了Co膜和Cu膜的电导率随薄膜厚度的变化关系。实验结果表明,Co膜和Cu膜的电学特性都具有明显的尺寸效应。比较了同时考虑表面散射和晶界散射的电导理论得到的电导率公式与实验结果,不同薄膜厚度电导率的理论结果与实验结果符合较好。提出了厚度作为金属薄膜生长从不连续膜进入连续膜的一个特征判据,并利用原子力显微镜(AFM)观测了膜厚在特征厚度附近的Co膜和Cu膜的表面形貌。     

Compositionally graded bismuth ferrite thin films

The compositionally graded (Bi_0.92La_0.08)(Fe_1−xZn_x)O₃ (x = 0.03, 0.07, and 0.13) thin film was layer-by-layer grown on Pt/Ti/SiO₂/Si(1 0 0) substrates without any buffer layers by radio frequency sputtering. This thin film has a pure polycrystalline perovskite structure with random orientation, a dense microstructure, and a low leakage current density. A large remanent polarization of 2P_r ∼ 142.00 μC/cm² and a good magnetic behavior of 2 M_s ∼ 27.52 emu/cm³ are demonstrated in such a thin film. The applied electric fields and measurement frequencies strongly affect its fatigue endurance, that is, its fatigue endurance was degraded with decreasing frequencies and electric fields.     

掺铝氧化锌薄膜的红外性能及机制

采用中频交流磁控溅射氧化锌铝(ZnO 2％Al2O3)陶瓷靶材的方法制备了掺铝氧化锌ZAO(ZnO：Al)薄膜．利用红外光谱仪测试了薄膜的红外反射性能,研究了薄膜厚度、基体温度和氩气压力对ZAO薄膜红外反射性能的影响规律,确定了制备具有高红外反射率的ZAO薄膜的工艺参数．     

Characterization of sputter—deposited TiPdNi thin films

TiPdNi thin films were prepared by magnetron sputtering onto unheated glass and silicon substrate.Atomic force microscope,energy-dispersive X-ray microsanalyzer,X-ray diffractometer,differential scanning calorimeter and optican microsope were used to characterize the films.It is found that the surface morphology of the films change during the sputtering process and a shift of about 3%Ti(mole fraction(content from the center to the edge of the substrate occurs.The freestanding as-deposited films undergo crystallization followed by three kinds of cooling conditions.For all these heattreated films,B2→B19→B19‘ two-stage phase transformation takes place.Many Ti2Ni and Ti2Pd type of precipitates are detected in the films.The constraint films on silicon substrate are crystallized at high temperature.After crystallization,the films show a two-way shape memory effect.     

纳米薄膜X射线吸收光谱的鉴定

采用X射线吸收光谱研究了热丝化学气相沉积(CVD)合成的纳米金刚石薄膜和脉冲激光沉积的纳米SiC薄膜.结果表明:纳米金刚石薄膜的碳K边X射线吸收精细结构光谱显示的激发峰相当于微米金刚石薄膜的蓝移,是量子效应的显著特征,证明制备的是纳米金刚石薄膜,与高分辨透射电镜的结果完全吻合;纳米SiC薄膜的硅K边X射线吸收精细结构光谱和扩展X射线吸收精细结构光谱也显示了纳米薄膜短程有序的结构特征,表明获得的是纳米SiC薄膜.     

Comparison of electrical characteristics for p-type and n-type organic thin film transistors using copper phthalocyanine

The p-type and n-type organic thin film transistors (OTFTs) were fabricated in the same experimental conditions by using hexadecahydro copper phthalocyanine (H₁₆CuPc) and hexadecafluoro copper phthalocynine (F₁₆CuPc) molecules, respectively. The mobilities of H₁₆CuPc and F₁₆CuPc-based OTFT devices in saturation region were measured to be ∼1.22 × 10⁻³ cm²/V s and ∼1.04 × 10⁻³ cm²/V s, respectively. The temperature dependence of the mobility and activation energy (E_a) for both OTFTs were measured in saturation and linear regions of the drain-source current. We found that the E_a of the F₁₆CuPc-based OTFTs was lower than that of H₁₆CuPc-based ones. The gate voltage (V_g) dependence of the field-effect mobility measured in linear region for the F₁₆CuPc-based OTFTs was more stable, i.e., weaker variation of the field-effect mobility with increasing V_g, than that of the H₁₆CuPc-based ones. The high electron affinity of the hexadecafluorine (F₁₆) in CuPc contributed to the effective electron accumulation in the active channel.