CuInS_2薄膜的溶胶-凝胶法制备与性能研究

采用溶胶-凝胶法,以CuCl2.2H2O和InCl3.4H2O为阳离子反应物,硫脲为硫源,去离子水为溶剂在玻璃衬底上制备CuInS2薄膜,在Ar气氛条件下400℃退火1 h。利用XRD衍射仪、扫描电子显微镜、NKD-7000 W光学薄膜分析系统等现代测试手段,研究了不同反应物Cu/In/S摩尔比对薄膜的晶相结构、表面形貌和光学性能的影响。结果表明:所制备的CuInS2薄膜为黄铜矿结构,沿(112)面择优取向生长。反应物Cu/In/S摩尔配比为1.5∶1∶6所生长的CuInS2薄膜晶粒尺寸分布均匀,表面平整致密。CuInS2薄膜的光学带隙宽度在1.97~2.05 eV范围内变化。     

中频磁控反应溅射制备硅基氮化铝薄膜

利用中频磁控反应溅射技术,以高纯Al为靶材、高纯N2为反应气体,在Si(111)衬底上成功制备出氮化铝薄膜.通过X衍射分析和原子力显微镜测试发现:提高N2分压和升高衬底温度有利于AlN(110)的形成;随着衬底温度的改变,AlN薄膜的表面粗糙度也在变化,当衬底温度为230℃时,RMS表面粗糙度最小.实验结果表明:升高衬底温度有利于制备(110)面择优取向的AlN薄膜,退火是影响氮化铝薄膜表面粗糙度的重要因素.     

掺Na制备柔性聚酰亚胺衬底CIGS薄膜太阳电池

研究了Na掺入对低温沉积柔性聚酰亚胺(PI)衬底Cu(In,Ga)Se2(CIGS)薄膜的结构和电学特性影响。研究结果表明:Na元素的掺入使Ga元素的扩散受到了阻滞,但对CIGS薄膜晶粒尺寸没有明显的影响,少量的Na可提高CIGS薄膜的载流子浓度和降低电阻率;Na的掺入可明显提高CIGS薄膜太阳电池的器件特性,通过优化掺Na工艺,制备的柔性PI衬底—CIGS薄膜太阳电池的最高转换效率达到10.4%。     

CuLaO2薄膜的制备和光电性能研究

采用传统的固相烧结法制备出纯相CuLaO2粉末,以此为靶材,首次采用射频磁控溅射法制备CuLaO2 薄膜并进行退火研究,得到了具有少量杂相的CuLaO2薄膜.其透过率在红外光区较高,近70%,可见光范Itt相时较低.CuLaO2 薄膜的电导率约6.7×10-4S/cm.对比分析了CuLaO2粉末及薄膜室温光致发光性能.测试结果表明,粉末和薄膜在450 am-650 am范围都有明显的发光带,而薄膜有少量的杂峰,杂峰是由于La203、Cu的氧化物及石英衬底的影响.     

沉积功率对多晶硅薄膜结构和光学性质的影响

采用等离子体化学汽相沉积(PECVD)方法在普通玻璃衬底上制备出多晶硅薄膜.研究了在不同沉积功率下的薄膜的沉积速率、晶相结构、吸收系数和光学禁带宽度.实验结果表明,沉积功率为140 W时薄膜沉积速率最大,达到7.8 nm/min.沉积功率为30 W多晶硅薄膜的晶粒较大,平均尺寸200 nm左右.沉积功率为100 W薄膜有较高结晶度,晶化率达到68%.薄膜样品在波长为500 nm的光吸收系数达到6×104 cm-1,在不同功率下样品的光学禁带宽度在1.70-1.85 eV之间变化.     

氧氩比和退火温度对AZO薄膜结构与性能的影响

在通氩气和不同比率氧氩混合气体的条件下,利用射频磁控溅射法在玻璃衬底上制备铝(Al)掺杂氧化锌(AZO)薄膜(溅射功率为180W,衬底温度为300℃),并对部分薄膜样品进行400℃或500℃退火处理.采用X射线衍射仪(XRD)、原子力显微镜(AFM)和分光光度计对薄膜的结构、表面形貌和光学性能进行测试研究.结果表明,制备的所有薄膜均呈现(002)晶面择优生长;与氩气溅射相比,当采用氧氩混合气体溅射时,生长的AZO薄膜晶粒尺寸显著增大;退火处理使2类薄膜的表面粗糙度都明显减小,晶粒也有所增大(7%~13%).其中,在氧氩比为1∶2的混合气体中制备的薄膜,经过500℃退火后,晶粒尺寸最大(39.4nm),薄膜表面更平整致密,在可见光区平均透过率接近最大(89.3%).     

PLD方法制备ZnO薄膜的特征温度研究

用PLD方法在S i(1 1 1)衬底上制备了ZnO薄膜.在薄膜的沉积过程中,用安装在激光脉冲沉积设备上的反射高能电子衍射仪(RHEED)对薄膜的生长进行了原位监测.结合薄膜的X射线衍射(XRD)分析和荧光光谱(PL)分析,发现达到或者超过650°C时生长的薄膜,结构和光学特性得到了显著的改善.     

衬底效应对LiTaO3薄膜制备的影响

用溶胶凝胶法在N型硅、P型硅、石英、铂、镍衬底上制备了钽酸锂(LiTaO3)薄膜,用XRD和SEM对钽酸锂薄膜性能参数进行了表征;发现掺杂少量环氧树脂能提高钽酸锂薄膜的均匀性,改善薄膜与衬底的粘附性;研究了衬底效应与薄膜厚度的关系,薄膜厚度超过0.2 μm,Ni衬底的XRD峰值强度几乎不再出现,说明衬底对薄膜初始结晶取向有重要影响;利用不同衬底上生长钽酸锂薄膜,XRD研究结果表明:N型硅、P型硅、石英衬底上只能制备多晶钽酸锂薄膜,铂衬底上制备的钽酸锂薄膜在(012)晶向有强大的择优取向性,镍衬底上制备的钽酸锂薄膜有更好的C轴择优取向性,C轴择优取向系数可达0.082。     

TiO2薄膜的火焰喷雾热分解法制备与自清洁研究

以钛酸丁脂(Ti(C4H9O)4)为前驱体,采用自制的火焰喷雾热分解装置在玻璃衬底上制备了TiO2自清洁薄膜.应用扫描电子显微镜(SEM)、X射线衍射(XRD)、紫外-可见透射光谱(UV-Vis)分析了薄膜的形貌、结构和透光性,并对薄膜的光催化性能和亲水性能进行了测试.结果表明,火焰喷雾热分解法制备薄膜要求雾滴先成液膜,再热分解为固体薄膜;采用火焰喷雾热分解法在玻璃衬底上成功制备的TiO2薄膜为锐钛矿晶型;探讨了沉积时间和退火温度对薄膜的结晶和自清洁性及光催化性能的影响,沉积时间长,退火温度高的薄膜的结晶度越高,光催化性能和亲水性越好;用该方法制备的温度约为400℃,退火温度为600℃薄膜,光透过率可超过70%.     

聚酰亚胺衬底CIGS薄膜附着性的改善

为改善聚酰亚胺(PI)衬底Cu(In,Ga)Se2(CIGS)薄膜的附着性,提出在NaF沉积前预先在Mo层上蒸发沉积100nm厚的In-Ga-Se(IGS)薄膜的新掺Na工艺。结果表明:这种IGS-NaF-CIGS式新工艺可显著改善CIGS薄膜的附着,而且CIGS薄膜材料和器件特性没有显著退化;新工艺促进了NaInSe2的生成,减少了In-Se二元相的残余,但也造成薄膜电阻率的升高和电池填充因子的下降,进而导致制备的PI衬底CIGS电池的转换效率由9.8%降至9.0%。综合考虑附着性的改善和器件效率的轻微下降,新工艺利大于弊,有很好的应用前景。     

Microstructures and fatigue-free properties of the La<Superscript>3+</Superscript> and Nd<Superscript>3+</Superscript> doped Bi<Subscript>4</Subscript>Ti<Subscript>3</Subscript>O<Subscript>12</Subscript> thin films prepared by modified sol-gel technique

Ferroelectric Bi_3.25La_0.75Ti₃O₁₂ (BLT) and Bi_3.15Nd_0.85Ti₃O₁₂ (BNT) thin films were fabricated on Pt/TiO₂/SiO₂/Si (100) substrates by a modified sol-gel technique. X-ray diffraction indicated that these films were of single phase with random polycrystalline orientations. The surface morphologies of the films were observed by scanning electron microscope, showing uniform, dense films with grain size of 50–100 nm. Well-saturated hysteresis loops of the films were obtained in metal-ferroelectric-metal type capacitors with Cu top electrodes at an applied voltage of 400 kV/cm, giving the remanent polarization (2P _r) and coercive field (2E _c) values of the films of 25.1 μC/cm² and 203 kV/cm for BLT, and 44.2 μC/cm² and 296 kV/cm for BNT, respectively. Moreover, these capacitors did not show fatigue behaviors after up to 1.75×10¹⁰ switching cycles at the test frequency of 1 MHz, suggesting a fatigue-free character. The influences of the La³⁺ and Nd³⁺ doping on the properties of the films were comparatively discussed. Supported by the National Key Basic Research and Development Program of China (Grant No. 2006CB932305) and the Natural Science Foundation of Hubei Province, China (Grant No. 2004ABA082)     

Li-Zn-Cu和Li-Zn-Co系铁氧体Mossbauer效应研究

在室温条件下,测量了多晶铁氧体（Ｌｉ０．５Ｆｅ０．５）０．７－ｘＺｎ０．３ＣｕｘＦｅ２Ｏ４（ｘ＝０．０;０．０３;０．０５;０．０７）和（Ｌｉ０．５Ｆｅ０．５）０．７ｙ＝Ｚｎ０．３ＣｏｙＦｅ２Ｏ４（ｙ＝０．０;０．０１;０．０２;０．０３）的Ｍｏｓｓｂａｕｅｒ谱,结果表明,离子代换使样品的Ｍｏｓｓｂａｕｅｒ谱变得复杂。所有谱线均包含一组强度很弱的顺磁双线亚谱。     

Fabrication of Stable Superhydrophobic Cupric Hydroxide Surface with Hierarchical Structure on Copper Substrate

Cupric hydroxide films with a new hierarchical architecture consisting of beautiful nanotubes and nanoflowers were directly fabricated on copper substrate via a solution-immersion process at a constant temperature of 23?℃. Stable superhydrophobic Cu(OH)₂ surface was obtained after Cu(OH)₂ films were modified with hydrolyzed 1H, 1H, 2H, 2H-perfluorooctyltrichlorosilane (C₈H₄Cl₃F₁₃Si, FOTMS). The surface morphology and composition of the film were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), respectively. Result shows that the surface of Cu(OH)₂ films directly grown on copper substrate was hydrophilic, whereas the modified Cu(OH)₂ films exhibited the superhydrophobicity with a water contact angle (CA) of about 160.8°, as well as a small sliding angle (SA) of about 1°. The special hierarchical structure, along with the slow surface energy leads to the high superhydrophobicity of the surface.     

乙酰胺-尿素-NaBr熔体中电沉积Tb-Mg-Ni合金的研究

在353?K的乙酰胺-尿素 NaBr熔体中，Ni（Ⅱ）一步不可逆还原为金属Ni,测得在Pt电极上α为0.21和D0为1.15×10-8?cm2•s-1；Cu电极上α为0.18和D0为1.44×10-6?cm2•s-1.Tb（Ⅲ）和Mg（Ⅱ）不能单独还原为Tb和Mg，但是可以被Ni（Ⅱ）诱导共沉积.由恒电位电解法得到非晶态的Tb Mg Ni 合金膜.合金中Tb的含量随着阴极电势的负移先增大而后减小，随Tb（Ⅲ）/ Ni（Ⅱ）摩尔比增大而增大，Tb的最大含量可达87.88%；Mg的含量随着阴极电势的负移而增大，最大可达12.78%，在Tb（Ⅲ）/Ni（Ⅱ））摩尔比为3.4/1，Mg（Ⅱ）/Ni（Ⅱ）摩尔比为8/1时，Mg/Ni原子比为2/1，符合Mg2Ni储氢合金的组成.     

真空阴极弧离子镀类金刚石碳膜

采用真空阴极弧离子镀的方法,以乙炔和氢气分别作工作介质,以氩气为稀释气体,研究了类金刚石碳（ＤＬＣ）膜的制备工艺及其结构和硬度。喇曼光谱分析表明,所得膜为典型的ＤＬＣ膜,表现为一个波数在１３００￣１７００ｃｍ＾－１的宽峰,工艺不同,喇曼光谱曲线的形状也略有变化。ＳＥＭ分别表明所得ＤＬＣ膜结构致密光滑。纳米探头硬度表明,ＤＬＣ膜表面硬度均高于１０ＧＰａ。     

Cu2O薄膜的制备及其光（电）催化降解甲基橙性能研究

采用循环伏安法,在1mol／L的KOH溶液中控制电位-1000mV--450mV（V8SEC）之间以1mV／s的速度扫描,在铜片基体上生成Ca2O薄膜。采用阴极电沉积法,以0．1moL／L的CH3COONa和0．02moL／L的（CH3COO）2Cu溶液作为电解液,控制恒电位-245mV（vs SEC）、室温条件下电沉积2h-3h在石墨板上制得Cu2O薄膜。分别用两种方法制得的薄膜催化剂对甲基橙溶液进行了光催化及光电催化降解。实验表明：铜片基体上膜的降解效果稍好于石墨基体上的膜;当加偏压后,偏压越大降解率越高。在反应器中,两种不同基体制备的薄膜,其光电催化降解甲基橙的降解率均可迭70％．     

STUDY ON SELECTIVE DISSOLUTION OF GOLD IN ALKALINE THIOUREA MEDIA

Manyresearches[1-3)ondissolutionofgoldinacidicsolutionsofthioureahavebeenreportedsincePlaksin.Generally,itwasconsideredthatthereaction(1)resultsindissolutionofgoldinthioureasolution.An[CS(NH,)sj' e~An ZCS(NH,)2E'~0.38V(1)NH,(NH)CSSC(NH)NH, ZH Ze~ZCS(NH,),E0-0.42V(2)CharleyWRetalthoughtthatthereaction(2)occurredfastly,theproductformamidinedisulfidewasanactiveoxidantandwasveryimportantduringthedissolutionofgold@@['j.However,theconclusionswerelimitedonlyinacidicthioureadissolutio…     

Influence of argon gas pressure on the ZnO:Al films deposited on flexible TPT substrates at room temperature by magnetron sputtering

Aluminium doped ZnO thin films(ZnO︰Al) were deposited on transparent polymer substrates at room temperature by rf magnetron sputtering method from a ZnO target with Al2O3 of 2.0 wt%. Argon gas pressure varied from 0.5 Pa to 2.5 Pa with radio frequency power of 120 W. XRD results showed that all the ZnO︰Al films had a polycrystalline hexagonal structure and a (002) preferred orientation with the c-axis perpendicular to the substrate. The grain sizes of the films were 6.3-14.8 nm.SEM images indicated the ZnO︰Al film with low Argon gas pressure was denser and the deposition rate of the films depended strongly on the Argon gas pressure, increasing firstly and then decreasing with increasing the pressure. The highest deposition rate was 5.2 nm/min at 1 Pa. The optical transmittance of the ZnO︰Al films increased and the blue shift of the absorption edge appeared when the Argon gas pressure increased. The highest transmittance of obtained ZnO︰Al films at 2.5 Pa was about 85% in the visible region. The electrical properties of the films were worsened with the increase of the Argon gas power from 1 Pa to 2.5 Pa. The resistivity of obtained film at 1.0 Pa was 2.79×10-2 Ω·cm.     

Effects of different CdCl_2 annealing methods on the performance of CdS/Cd Te polycrystalline thin film solar cells

In this paper, the effects of different Cd Cl2 annealing methods, including vapor annealing and dip-coating annealing, on the performance of Cd S/Cd Te polycrystalline thin-film solar cells are studied. After annealing, the samples are lightly etched with 1% bromine in methanol to remove surface oxides. Both annealing methods give Cd Te polycrystalline thin films with good crystallinity and complete structure. For solar cells containing the annealed Cd Te films, cell efficiency first increases and then decreases as the concentration of Cd Cl2 solution used for dip-coating annealing increases, and the optimized Cd Cl2 concentration is 12%. The uniformity of the performance of all cells is analyzed by calculating the relative standard deviation for each parameter. The uniformity of cell performance can be improved dramatically by dip-coating annealing instead of vapor annealing. Most notably, an appropriate concentration of Cd Cl2(12%) acts as a protective layer that is conducive to realizing uniform high-performance Cd S/Cd Te solar cells. According to the location of depletion regions, the Cd Te films treated by dip-coating annealing show a relatively low doping concentration, except for the sample treated with a Cd Cl2 concentration of 6%, which is consistent with the changes of short-circuit current density of the cells. It is believed that these results can be applied to the large-scale production of Cd Te polycrystalline thin-film solar cells.     

Ferromagnetism of Zn1−x Cu x O polycrystalline made by solid state reaction

The Zn1-xCuxO polycrystalline materials were prepared by doping CuO into wurtzite ZnO through solid state reaction. The high concentration of copper doping in ZnO exhibited remarkable room temperature ferromagnetism. The Experiments showed that the magnetization saturation rose with the increase of Cu content. For the low Cu content sample, the hysteresis loop was slightly tilted which indicated that the diamagnetism coexisted in this sample. The temperature dependence of magnetization of Zn1-xCuxO revealed that the magnetic exchange coupling depended on the doping concentration of Cu and there were many different local environments for magnetism. The measured hysteresis loop and temperature dependence of magnetization were overall performance of the magnetism coming from a wide distribution of ferromagnetic exchange couplings.