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激光加工制备的Mn-Cu合金涂层对于纳米多孔涂层的制备具有重要的研究意义.本文采用激光熔覆与快速激光熔凝相结合的方法在中碳钢基体表面制备了成形良好、稀释率低并与基体成冶金结合的Mn-Cu合金涂层.对合金涂层进行了特定参数不同时间的电解腐蚀处理,并对处理后的涂层材料进行X射线衍射分析,研究了Mn-Cu合金涂层在电解腐蚀过程中的晶体结构改变过程.结果表明,未经处理的合金涂层具有单相固溶体结构(Cu,γMn);在电解腐蚀过程中随着Mn元素的溶解.有新的纯Cu晶体形核长大,剩余的(Cu,γMn)固溶体中的Mn含量也逐渐降低;经彻底电解腐蚀后,涂层的晶体结构由单相(Cu,γMn)转变为具有纳米多孔结构的单相Cu. 相似文献
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电子束照射下ZnS向Zn纳米薄膜的转变 总被引:1,自引:0,他引:1
金属纳米晶体材料由于其晶粒小、界面密度高 ,表现出独特的物理、化学性能[1] ,为传统材料的改性和新型功能材料的开发开辟了新路。目前制备纳米材料的方法有金属蒸发凝聚 -原位冷压成型法、机械合金化法、非晶晶化法、电解沉积法以及电子束照射法等[2 ] 。这些方法各有特点 ,其中电子束照射法优点在于真空度高 ,制备纳米微粒纯净度高、尺寸易于控制等。本研究组已用这种方法分别从Al2 O3和MoO3制备了Al和Mo纳米微粒[3 ,4 ] ,并研究了在电子束照射下纳米微粒的结合过程。本文报道了在电子束照射下用ZnS制备Zn纳米薄膜的实验… 相似文献
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通常多晶铜中会含有一定数量的生长孪晶或退火孪晶。但是,由于一般生长孪晶的尺寸和分布很不均匀,数量也较少,很难研究它们在材料力学行为中的作用,因此孪晶对铜的力学行为的影响还不清楚。最新研究发现,可以利用电解沉积法,通过引入大量的生长孪晶和降低孪晶尺寸来制备纳米结构铜。纳米量级的孪晶结构对力学行为的影响十分明显,但对其作用机理的研究十分有限。本工作对一种由电解沉积法制备的含有独特的高密度纳米孪晶片层结构的多晶纯铜进行室温轧制,通过观察其微观结构,探讨了孪晶结构特别是纳米量级的孪晶片层结构的形变行为以及孪晶片层尺寸对其形变行为的影响。 相似文献
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ZnS纳米粒子的制备与表征 总被引:2,自引:0,他引:2
采用水热法以乙酸锌和硫化钠为原料,尿素为矿化剂制备ZnS纳米粒子。讨论了反应温度,反应时间,矿化剂浓度对ZnS纳米粒子尺寸和形貌的影响。通过XRD、TEM、UV-vis吸收光谱表征了ZnS纳米粒子的形貌、尺寸和结构。结果表明,采用尿素作为矿化剂,在较宽温度范围(120~200℃)内均能制备出分散良好、平均粒径为12nm的球形ZnS纳米粒子。 相似文献
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S. Mostafa Hosseinpour-Mashkani Masoud Salavati-Niasari Fatemeh Mohandes K. Venkateswara-Rao 《Materials Science in Semiconductor Processing》2013,16(2):390-402
For the first time, (1,8-diamino-3,6-dioxaoctan)copper(II) sulfate, [Cu(DADO)]SO4, and bis(propylenediamine)copper(II) sulfate, [Cu(pn)2]SO4, complexes as copper precursors have been used to prepare CuInS2 (CIS) nanoparticles in the presence of microwave irradiation. InCl3 anhydrous, thioacetamide (TAA), and propylene glycol were used as indium source, sulfur precursor, and solvent, respectively. Additionally, sodium dodecyl sulfate (SDS) was used as a capping agent. In this method, microwave irradiation created the activation energy for dissociating the precursors and led to the formation of CuInS2 nanoparticles. The effect of preparation parameters such as microwave power, irradiation time, and type of copper precursor on the particle size of the products was studied. To fabricate a solar cell, CdS film was directly deposited on top of the CIS film through the chemical bath deposition method. The as-deposited CdS/CuInS2 films were used for the photovoltaic measurements. According to I–V curves, it was found that the CIS nanoparticles synthesized by [Cu(DADO)]SO4 complex as precursor was better for solar cell applications. 相似文献
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Silver and copper nanowires have been synthesized using a scalable method of AC electrodeposition into porous aluminum oxide templates, which produces gram quantities of metal nanowires ca. 25 nm in diameter and up to 5 and 10 μm in length for Ag and Cu, respectively. The nanowires have been used to prepare polystyrene nanocomposites by solution processing. Electrical resistivity measurements performed on polymer nanocomposites containing different volume fractions of metal indicate that low percolation thresholds of nanowires are attained between compositions of 0.25 and 0.75 vol %. 相似文献
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Chang-You Chen Chang E.Y. Li Chang Szu-Hun Chen 《Electron Devices, IEEE Transactions on》2001,48(6):1033-1036
Backside copper metallization of GaAs MESFETs using TaN as the diffusion barrier was studied. A thin TaN layer of 40 nm was sputtered on the GaAs substrate before copper film metallization, as judged from the data of X-ray diffraction (XRD), Auger electron spectroscopy (AES), and cross-sectional transmission electron microscopy (TEM), the Cu/TaN films with GaAs were very stable without interfacial interaction up to 550°C annealing; the copper metallized MESFETs were thermally stressed at 300°C. The devices showed very little change in the device characteristics (<3%) after thermal stress, and the changes of the electrical parameters and RF characteristics of the devices after thermal stress were of the same order as those devices without Cu metallization, these results show that TaN is a good diffusion barrier for Cu in GaAs devices and the Cu/TaN films can be used for the backside copper metallization of GaAs MESFETs 相似文献
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Li C Liang J Niu J Liu S Li G Bai J Zhang A Ding R 《Journal of electron microscopy》2011,60(5):301-305
This study employed a co-precipitation method to synthesize copper-modified hydroxyapatite (HA) powders, where Cu(2+) ions had entered the structure of HA and occupied Ca(1) sites in the columns parallel to the c-axis. Through a hydrothermal treatment, hollow HA/copper (Cu(2)O and/or Cu) microspheres with core-shell structures were prepared in solutions containing glucose, sodium carbonate and sodium citrate. When prolonging the reduction time, Cu(2+) ions dissolved from copper-modified HA were reduced by glucose initially to Cu(+) ions and then to Cu atoms, which would precipitate as copper on the surface of HA. The formation of microspheres with hollow structures was explained by the Kirkendall effect which states that diffusion behaviors of ions were different for HA and copper precipitations. Hybrid HA/copper powders might find their applications in gas sensors, catalysts, electrodes and so on. 相似文献
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Chang-You Chen Li Chang Edward Yi Chang Szu-Houng Chen Yueh-Chin Lin 《Solid-state electronics》2002,46(12):1409-2088
The performance of GaAs power MESFET’s using backside copper metallization has been evaluated. 10 nm Ta metal was used as the diffusion barrier between GaAs and Cu for copper film metallization in this study. Microstructural characterization shows that the Cu/Ta films with GaAs remained stable up to 400 °C, indicating that Ta is a good diffusion barrier for Cu in GaAs MESFET’s. A copper metallized 6 mm power MESFET was thermal stressed to test the device stability. After annealing at 200 °C for 3 h, the devices showed very little degradation in power performance, and the thermal resistance of the device was 65 °C mm/W with 1.4 W/mm DC input power. Results in this study demonstrate that the feasibility of using Cu/Ta films for the backside metallization of GaAs power devices with stable electrical and thermal characteristics. 相似文献
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采用稻米中淀粉作为稳定剂,氢氧化钠作为还原剂的方法制备了银铜纳米颗粒。利用扫描电子显微镜在高倍数下观察Ag-Cu纳米颗粒表面形貌;通过透射电镜定性分析了银铜纳米颗粒的空间结构;通过X线光电子能谱分析得到粉末中元素成分及其相对含量;通过热重分析定量地确定了太阳能电池的烧结工艺;通过太阳能模拟器分别对正电极浆料中加入纳米Ag-Cu颗粒(质量分数为10%)前、后的多晶硅电池片进行光电性能测量。结果显示,在银浆中加入了质量分数为10%的纳米Ag-Cu后,电池片的各参数都有提高,其光电转化效率提高了5.65%。实验表明,利用Cu纳米颗粒取代部分Ag纳米颗粒,可提高电池的光电转化效率。 相似文献
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Sol–gel technology has been applied for preparation of ZnO:Cu films. The proposed facile approach allows obtaining a wide variety of copper doped zinc oxide systems, revealing different structural and optical behaviors. The work presents structural and optical studies depending on Cu concentration and thermal treatments in the range of 500–800 °C. The structural analysis is performed by X-Ray diffraction (XRD). It reveals that small Cu addition enhances the film crystallization. Increasing copper concentration results in deterioration of ZnO:Cu crystallization. XRD study manifests no Cu oxide phases in ZnO:Cu film structure for lower Cu additions. For a specific higher copper concentration, an appearance of a small fraction of copper oxide is detected. Vibrational properties have been characterized by FTIR spectroscopy. The effect of the copper introduction into ZnO reveals a slight change of optical properties compared to ZnO films for certain Cu ratios. ZnO:Cu films with higher copper contents manifest different optical behaviors with very high transparency in spectral visible range. 相似文献
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Semiconductor industry currently utilizes copper wafer bonding as one of key technologies for 3D integration. This review paper describes both science and technology of copper wafer bonding with regard to present applications. The classification of Cu bonding, bonding mechanisms, process developments, its microstructure evolution, as well as other characterizations are reviewed. Researches about patterned Cu bonding, future prospects, and 3D integration using Cu bonding are discussed in this paper. 相似文献
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为了研究激光选区金属化技术中,激光与尖晶石型化合物的相互作用机理,选用质优价廉、具有尖晶石结构的可见光和近红外光敏催化物质羟基磷酸铜(Cu2(OH)PO4)作为研究对象,利用X射线光电子能谱技术,探讨了波长为1064nm纳秒脉冲光纤激光、连续光纤激光和波长为355nm的纳秒脉冲紫外激光与羟基磷酸铜的相互作用机理。结果表明,3种激光都能将羟基磷酸铜中的+2价铜元素(Cu2+)还原为+1价铜元素(Cu+),但还原过程随激光功率(0.13W~3.89W)或激光能量密度(2.76J/cm2~25.48J/cm2)的变化呈现不同的规律; 结合羟基磷酸铜的热性能分析和紫外可见光吸收光谱分析,初步判断,在上述还原过程中,可能同时存在光热反应和光化学反应。该研究为羟基磷酸铜作为一种新型的激光活性物质提供了理论基础。 相似文献
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Copper thin films with high conductivity and good resistance to electromigration can be used in advanced electronic devices.
However, the poor corrosion resistance of copper must be overcome. This work elucidates the possibility of using a self-forming
passivation layer to prevent copper oxidation in lightly indium-doped copper thin films deposited directly on glass substrates
and annealed under various oxygen atmospheres. The resistivity of the studied film declined gradually as the film was annealed
at an elevated temperature because of the grain growth of the Cu film and the precipitation of indium from the In-doped Cu
thin film, as revealed by X-ray diffraction, four-point probe measurements, and transmission electron microscopy. A copper
film with high indium content exhibited superior passivation when the film was annealed in an oxygen-rich ambient, but it
exhibited high resistivity because of its high indium content. The electrical and passivation properties demonstrated that
indium is a promising alloying element for use in copper films for future metallization structures and thin-film transistors. 相似文献