化学沉积法中立方相和六方相CdS薄膜的制备及其特性

采用化学沉积法制备了多晶CdS薄膜;利用X射线衍射仪、原子力显微镜、透射光谱以及光电导测试等方法表征了CdS薄膜的晶体结构、光学特性和电学特性。结果表明:通过改变反应液中Cd2 离子浓度(0.002~0.008mol.L-1)和提高沉积温度(80~90℃)来加快沉积速率,CdS薄膜晶相由六方相(H)向立方相(C)转变,且禁带宽度随Cd2 离子浓度增大逐渐变大;当Cd2 离子浓度从0.002mol.L-1增加到0.005mol.L-1时,薄膜呈六方相,浓度为0.006mol.L-1时出现六方与立方两种晶相共存,而浓度为0.008mol.L-1时薄膜转变为立方相。CdS薄膜表面形貌、光学特性、电学特性也随Cd2 离子浓度的增大而有规律的变化。     

CIGS电池缓冲层CdS的制备工艺及物理性能

在含有醋酸镉、醋酸氨、硫脲和氨水的水溶液中,化学沉积CdS半导体薄膜,薄膜的厚度与搅拌强度有很大关系,表明薄膜的生长速度是由OH-和SC(NH2)2的扩散传质为控制步骤。CdS薄膜的电阻率在104~105Ω.cm之间。CdS薄膜的晶格在乙酸胺浓度较小时,为六方晶和立方晶混合结构;乙酸胺浓度较大时,为立方晶结构。利用六方晶与立方晶混合的CdS制备的CIGS太阳电池,光电转换效率最大可达12.1%,3.5×3.6cm2小面积组件为6.6%。立方相CdS制备的最佳电池效率达到12.17%。两种晶相结构的CdS薄膜对CIGS太阳电池的性能影响没有明显的差别。     

电沉积制备中络合剂对光伏材料CdS的影响

利用电沉积（Electrodeposition)方法来制备六方相的CdS薄膜。实验指出从0．04mol/L Na2S2O3,0.04mol/L,CdSO4和0.04mol/L柠檬酸钠组成的溶液中，在pH值为5．4，温度为60℃的条件下，在ITO玻璃上电沉积得到CdS的前驱体。在300℃氮气氛下中热处理1h后，经X射线衍射（XRD）分析表明薄膜是呈六方相的CdS，且几乎沿（002）方向定向生长。扫描电镜（SEM）表明CdS晶粒为亚微米尺寸。研究表明，利用这种方法，可以得到结晶良好的六方相CdS薄膜。     

化学沉积法制备CdS薄膜及性质研究

利用化学沉积(CBD)的方法制备立方相的CdS薄膜。实验表明，在无搅拌、柠檬酸钠作为络合剂的条件下，在溶液的配方为0．02mol/L的CdCl2、0．02mol/L的柠檬酸钠、0．05mol/L的CS(NH2)2的体系中，当pH值为11．5，溶液温度为80℃时，在ITO玻璃上沉积得到CdS薄膜的前驱体，再把所得的前驱体在350℃，N2保护下热处理两个小时经x射线衍射(xRD)和扫描电镜分析，表面薄膜是结晶良好、立方相、表面均匀光滑的CdS薄膜。随着热处理温度的提高，CdS薄膜的晶化程度有很大的提高，晶粒有明显的长大，其光学性能也有很大的改善。     

化学沉积制备CdS及超声振动处理

在无搅拌、氨水作为络合剂的条件下得到六方相的CdS薄膜，并通过对比超声振动处理和未超声振动处理样品的X射线衍射谱指出文献中在搅拌条件下制备的CdS薄膜相难以确定的原因。通过SEM、EDX和UV／VIS等测试仪器的分析表明超声振动可以很好的改善薄膜的性质使之适合用作太阳电池的n窗口材料，从而降低成本。     

稀土元素(Gd,Y)掺杂CdS薄膜的制备及其性能研究

采用化学水浴法两次沉积CdS,结合电子束真空蒸发法在两层CdS之间引入稀土层,制备含有不同厚度稀土Gd、Y掺杂层的CdS多晶薄膜。利用XRD、SEM、EDX、UV-VIS透射光谱和霍尔效应测试仪对薄膜的晶型、表面形貌、化学组成、光学及电学性能进行研究。结果表明:未掺杂的薄膜为沿(111)晶面择优生长的立方相闪锌矿结构,导电类型为n型。含有稀土Gd(Y)掺杂层的CdS多晶薄膜为立方相和六方相的混合结构,导电类型仍为n型,薄膜的均匀性和致密性得到改善,薄膜中Cd和S的原子比更接近CdS的化学计量比,稀土掺杂可提高CdS薄膜在可见光范围内的透过率,使薄膜载流子浓度增大、导电性能明显增强。     

水浴温度对化学水浴法沉积CdS和ZnS薄膜性能的影响

分别采用硫酸镉、硫脲、氨水溶液体系及硫酸锌、硫脲、氨水、联氨溶液体系,以化学水浴法(CBD)制备CdS和ZnS薄膜,研究水浴温度对薄膜沉积过程及性能的影响,分析不同水浴温度下沉积得到的CdS和ZnS薄膜性能的差异。试验表明,随着水浴温度的升高,薄膜的沉积速率增大,致密度变高,薄膜的禁带宽度更接近其理论值。当水浴温度大于70℃时,CdS薄膜的沉积速率远大于ZnS;随着水浴温度的升高,CdS晶粒逐渐变小而ZnS晶粒逐渐变大,CdS薄膜中S/Cd原子比逐渐下降,而ZnS薄膜中S/Zn原子比逐渐升高;ZnS薄膜能够透过更多短波高能光子且禁带宽度大于CdS,有利于提高太阳电池的效率。     

电沉积法制备CuxS薄膜及其性质研究

利用电沉积的方法制备CuxS薄膜，研究了不同的络合剂，不同的硫源及不同的热处理温度对电沉积制备CuxS薄膜性质的影响。研究发现：不同的络合剂可以制备得到不同相的CuxS薄膜，用EDTA作为络合剂的时候得到是六方相的Cu2S其主要晶面是(102)，当用柠檬酸钠作为络合剂的时候得到的是单斜的Cu31Sl6其主要晶面是(842)。当用Na2S2O3作为硫源的时候得到的是单斜的Cu31S16其主要晶面是(842)，当用硫脲作为硫源的时候得到是六方相的CuxS其主要晶面是(102)。随着热处理温度的提高，薄膜的结晶程度有了很大的提高，晶粒有了明显的长大，不同温度的热处理证实了CuxS薄膜的生长是沿着[102]方向定向生长的。     

ILGAR法制备CdS薄膜新工艺的研究

采用一种薄膜制备的新方法-离子层气相反应法(ILAR)，以CdCl2为前驱体，H2S为硫源制备了CdS薄膜。利用XRD、SEM、AFM、XPS及UV—VIS透射光谱等测试分析方法对薄膜的晶型、表面化学组成、表面形貌、膜厚增长速度及光学性能进行了研究。实验结果表明：ILGAR法制备的CAS薄膜表面较致密、均匀、附着性好；在0．05MCdCl2前驱体溶液浸渍处理，薄膜以-2．8nm／cycle的恒定速率增长，且薄膜晶体沿立方(111)面具有明显的择优取向生长；400℃热处理1h，发生立方→六方晶型转变，最终为六方与立方混相结构，择优方向转为六方(002)面；薄膜经热处理后在可见光处的吸收峰发生红移，其禁带宽度降低，并且会随着膜厚的增加进一步降低。     

溶液pH值对化学浴沉积CdS薄膜性能的影响

研究了溶液pH值对化学浴沉积CdS薄膜表面形貌及光学性能的影响.在CdSO4、硫脲和氨水的混合溶液中,在玻璃基底上制备了CdS薄膜.实验表明,pH值对CdS薄膜的表面形貌有很大影响,pH=11.6条件下CdS薄膜致密度最高;随着pH值的增加薄膜的可见光透过率增加,薄膜中S/Cd比减小;但是,pH值对CdS薄膜的晶体结构没有影响.用扫描电镜观察了CdS薄膜的表面形貌;用XRD检测了CAS薄膜的晶体结构;用分光光度计检测了薄膜的透过率;用EDS检测了薄膜成分.     

Hydrogenation effect on structural,electrical and optical properties of CdS thin films for solar cell

Adsorption effects would be expected to be of considerable importance with thin films because of the changes in electron location accompanying adsorption. The effects of hydrogenation on structural, optical and electrical properties of the CdS thin films have been reported. GIXRD patterns shows that films have polycrystalline nature with a hexagonal structure. The optical band gap increased after hydrogenation of the film. The variation of conductivity of CdS films have been investigated depending upon the applied voltage at room temperature. The resistivity increased after hydrogenation of the films. Hydrogenated thin films can be used in solar cells because hydrogen plays an important role to modify the physical properties.     

HIGH EFFICIENCY THIN FILM CdS/CdTe SOLAR CELLS†

Cadmium telluride is a most promising thin film photovoltaic material as shown by the higher than 10% efficient CdS/CdTe heterojunction solar cells. In this work, thin film CdS/CdTe solar cells have been prepared using CdS films grown from an aqueous solution and p-CdTe films deposited by metalorganic chemical vapor deposition (MOCVD) and close-spaced sublimation (CSS). The solution-grown CdS films, with high photoconductivity ratios and good optical transmission, are well-suited for optoelectronic devices. The CdTe films deposited by CSS show considerably better microstructure than those by MOCVD because of the higher substrate temperature used in the CSS process. The properties of CdS/CdTe heterojunctions have been studied. Solar cells of 1 cm2 with an AM 1.5 efficiency of 14.6%, verified at the National Renewable Energy Laboratory, have been CdTe films     

Thin CdS films prepared by metalorganic chemical vapor deposition

Polycrystalline CdS thin films have been deposited on borosilicate glass substrates coated with ITO film by metalorganic chemical vapor deposition using dimethyl cadmium and diethyl sulfide as source materials. The growth of CdS film occurred at substrate temperatures within the range of 280–360°C. The deposition rate increased with increasing VI/II molar ratio at any substrate temperature and showed a maximum value at the VI/II molar ratio of 4. The grain size of as-deposited CdS film prepared at substrate temperatures from 300°C to 360°C was about 0.1 μm. The CdS films consist of hexagonal form with a preferential orientation of the (0 0 2) plane parallel to the substrate. Thin CdS film with high optical transmittance was prepared at 350°C with the VI/II molar ratio of 4. The CdS film deposited by MOCVD may be used as a window layer for CdS/CdTe solar cell.     

Cd1-xZnxS薄膜结构表征与光电化学性能研究

利用超声喷雾热分解方法在ITO导电玻璃上成功制备了高质量低成本的Cd1-xZnxS薄膜,并利用X射线衍射(XRD)、扫描电镜(SEM)、紫外可见光谱(UV-vis)等表征手段对其进行了结构、形貌和光学性质表征,并采用锁相放大技术研究了Cd1-xZnxS电极的光电流作用谱图。结果表明,利用喷雾热分解方法能制备出结晶完好均匀致密的Cd1-xZnxS薄膜,其中CdS呈六角相,Cd1-xZnxS(0相似文献   

CdS/CdTe太阳电池中CdS多晶薄膜的结构和光学性能

采用XRD,AFM,XPS和光学透射谱对化学水浴法制备的CdS多晶薄膜进行了测试分析。刚沉积的CdS多晶薄膜均匀、透明、致密,主要呈现立方结构;Cd和S的原子百分比约为1 10;能隙(Eg)约为2 47eV。在不同温度下后处理会出现六方结构和3CdSO4·8H2O衍射峰,同时晶面择优取向发生了变化。通过沉积高质量的CdS薄膜,获得了效率约13 4%的CdS/CdTe小面积太阳电池。     

Preparation and properties of CdS thin films prepared on cold substrate as a window layer for solar cells

CdS films, usually, prepared on hot substrate at temperature range from 180 to 220°C. The electrical properties of the films are dependent on many parameters such as film thickness, deposition rate, film structure and substrate temperature. To control all these parameters to get film resistivity suitable for manufacturing solar cells, it needs a lot of precautions. CdS prepared on cold substrate could be the solution for this problem. Evaporation of CdS film at constant evaporation rate, then annealed in open air up to 600°C according to the film thickness. The resultant film have been studied. The properties of the films were comparable to the films prepared by the other methods with less control complexity.     

Studies on optical and electrical properties of SILAR-deposited CuO thin films

CuO thin films prepared by SILAR technique using aqueous solutions of various pH values and their characterization are presented in this report. The pH dependence on structural, morphological, optical and electrical properties of the prepared films is studied. Thickness of films is found to vary in between 0.52 and 0.82 µm. Microstructural parameters such as crystallite size, strain and dislocation density of the film have been evaluated. The crystallographic behaviour of the film has shown that all the coated thin films are in monoclinic structure with (002) preferred orientation. The size of the crystallites is found to increase with the pH values. Surface morphological behaviour of the films prepared using different pH values are analysed. Optical properties of the films were analysed from absorption and transmittance studies of CuO thin films. Band gap energy values of CuO thin films have been found to decrease from 2.12 to 1.91 eV with increasing pH values of the solution. The thin film formed at a solution pH 11 has shown least resistivity and high carrier concentration. The I-V characteristics of n-Si/p-CuO heterojunction under 200-watts halogen lamp illumination show open-circuit voltage of ~ 0.37 V and short-circuit current of ~1.02 × 10^?6 A.     

Bromine doping effect on some properties of CdS films

The suitability of bromine as an anionic dopant influencing the properties of CdS thin films is discussed in this paper. The as-deposited films were characterised respectively by XRD, SEM, UV-vis-NIR spectrophotometer and two-point probe setup. All the films appear to be polycrystalline in nature exhibiting hexagonal crystal structure with a (002) preferential growth texture. The 2θ value of the (002) plane shifts towards lower Bragg angle with doping inferring an expansion in their lattice volumes. Increased transparency and blue shift in optical band gap value are observed for the doped films. Electrical resistivity decreased with increase in Br-doping concentration. Increased transparency, widened band gap and decreased electrical resistivity values achieved confirm that Br is a suitable anionic dopant that can strongly influence the physical properties of pure CdS towards future optoelectronic devices.