溅射Cu-Zn-Sn金属预制层后硫(硒)化法制备Cu2ZnSn(SxSe1-x)4薄膜及其光伏特性

采用溅射工艺制备Cu-Zn-Sn金属预制层并尝试在多种退火方案(硫化退火、硒化退火、不同温度下硫化后硒化)下对其进行退火处理,探索出一种只需采用金属预制层即可完成CZTSSe制备的退火工艺制度。通过扫描电镜对比研究了不同退火制度下Cu_2ZnSn(S_xSe_(1-x))_4薄膜的形貌差异,发现低温硫化后硒化工艺可以有效减少因硫化温度过高引起的薄膜中孔洞较多的问题,有利于薄膜的平整与致密化。在此基础上,采用X射线荧光光谱、扫描电镜、X射线衍射及拉曼光谱对不同硫化温度(200℃、300℃、400℃、500℃)下硫化后硒化工艺制备的Cu_2ZnSn(S_xSe_(1-x))_4薄膜的成分、形貌、物相结构及结晶性能进行了表征和分析。结果表明,300℃下硫化后硒化获得的Cu_2ZnSn(S_xSe_(1-x))_4较其他温度下硫化后硒化获得的产物有着更好的形貌及结晶性能,其器件的光电转换效率为2.09%,远高于500℃下硫化后硒化工艺所得薄膜器件的效率(0.94%)。     

铜锌锡硫硒(CZTSSe)薄膜的制备工艺及性能表征

本文以油胺为溶剂,采用液相法制备了Cu2ZnSnS4(CZTS)纳米颗粒,通过CZTS纳米浆滴涂法制备了CZTS薄膜,而后经固态硒源硒化工艺得到了CZTSSe薄膜,研究了制备工艺条件反应温度、气压、物质配比及退火温度等对样品的晶体结构及成分的影响。采用X射线衍射仪(XRD)、热重-差示扫描量热法(TG-DSC)、能谱分析(EDAX)对制备的CZTS粉末和CZTSSe薄膜样品进行了表征,结果表明在化学计量比和保压的条件下可得到单相性较好的前驱体粉末,由此得到的CZTSSe薄膜在500℃的硒化退火温度下能够形成具有单一锌黄锡矿结构、结晶程度较好的薄膜;由EDAX的成分分析结果可知,薄膜具有贫铜的成分,而且,随着温度的升高,Se元素含量增加最后趋于平稳,而S元素含量先减少后有增加趋势。     

硅(100)衬底表面快速热退火制备硒纳米晶薄膜的结晶动力学

采用超高真空气相沉积系统在Si(100)衬底上制备非晶硒(Se)薄膜,然后快速热退火制得Se纳米晶薄膜。SEM观察结果表明,当热退火温度高于140℃,薄膜表面形貌从条状裂纹逐渐变成孤立的六角块状结构。Raman和XRD测试分析发现,退火后的Se纳米晶均为三角晶型结构,当退火温度高于140℃时,Se开始沿(100)方向择优取向结晶。分析得出,在Si(100)衬底上的Se晶粒(100)晶面的激活能比(101)晶面的激活能低,因而在(100)面上的结晶速率比(101)面上的结晶速率大,使得Se在(100)方向择优结晶。笔者认为这是因为Si(100)衬底对Se的结晶具有诱导作用,致使硒的结晶具有各向异性。     

硒化方式对CuInSe2薄膜结构、成分和形貌的影响

采用直流磁控溅射技术,首先在玻璃衬底上制备Mo薄膜,然后制备CuIn预制层。以固态硒粉为硒源,采用硒薄膜法和硒蒸气法两种硒化工艺,经过三步升温硒化方式对CuIn预制膜进行硒化制备CuInSe2薄膜。通过X射线衍射、能量散射谱和扫描电镜测试分析手段,分析CuIn预制膜和每一步硒化热处理后薄膜结构和形貌的变化。结果表明:两种方法硒化后均形成具有单一黄铜矿相结构的CuInSe2薄膜,薄膜具有(112)面择优取向,硒蒸气法形成的晶粒较大,但均匀性差。     

基底温度对四元叠层硒化法制备铜铟镓硒(CIGS)薄膜的影响

利用四元叠层硒化法制备了铜铟镓硒(缩写为CIGS)薄膜,重点分析了在叠层法制备CIGS薄膜过程中,基底温度对CIGS薄膜的晶体结构,表面形貌以及各种元素沿深度分布的影响.实验结果表明,在叠层法制备CIGS薄膜时,发现在550℃的基底温度时,不经过退火便可以生成CIGS晶体,表面Ga的含量处于比较合适的范围.而基底温度为500℃,450℃时,只能生成铜铟硒(CIS)晶体,Ga元素表面的含量较少,主要分布在薄膜底部.     

钛酸锶钡(BST)薄膜晶化过程研究

采用射频磁控溅RF-magnetron sputting)法制备了钛酸锶钡(BST)薄膜,用快速热处理(RTA)和常缮规热处理(CFA)对薄膜进行晶化.利用AFM、XRD等技术分析了钛酸锶钡薄膜的晶化过程,以及不同退火温度和退火方法下薄膜的晶粒、晶相特性.实验表明:钛酸锶钡薄膜在500℃开始结晶,到700℃左右时结晶比较完善,晶化过程中没有出现择优取向;从表面形貌和X射线衍射图综合分析,快速退火的晶化效果要优于常规退火.     

硒化温度对铜铟镓硒太阳能电池吸收层性能的影响

用预制膜硒化法制备铜铟硒系太阳能电池的吸收层CIGSe薄膜,用X射线荧光分析(XRF)、扫描电子显微镜(SEM)、X射线衍射分析(XRD)和拉曼谱分析(Raman)以及基于霍尔效应分别测定或观测CIGSe薄膜的成分、表面形貌、结构以及电阻率和少数载流子迁移率,研究了在近玻璃软化点520-560℃区间硒化温度对薄膜成分、表面形貌、结构和电学性能的影响。结果表明:当硒化温度在520-560℃时,CIGSe薄膜的成分和表面形貌保持不变,但是随着硒化温度的升高CIGSe薄膜中有序缺陷相(ODC)和Cu-Se短路相增加,提高了薄膜内的缺陷浓度,使薄膜的少数载流子迁移率降低、电阻率增大。     

电沉积制备CIS太阳能电池吸收层材料

在Cu衬底上用电沉积的方法沉积金属In,再通过硒蒸气硒化处理成功制备了CuInSe2薄膜.用X射线衍射(XRD)、扫描电镜(SEM)、X射线能谱(EDS)对制备的薄膜进行相组成、微观结构、表面形貌等分析,研究了制备工艺条件对薄膜性能的影响.结果表明:电沉积的In在低温热处理阶段与衬底Cu扩散形成Cu-In合金预制层,预制层在硒化阶段生成CuInSe2,合金中过量Cu生成CuSe表面层,未反应的In转变为Cu16In9,形成Cu衬底/Cu16In9/ CuInse2/CuSe结构.     

硒化温度对CuInSe2薄膜性能的影响

采用中频交流磁控溅射方法沉积Cu-In薄膜,并采用固态源硒化方法制备CuInSe2(CIS)薄膜,考察了硒化温度对CIS薄膜性能的影响.采用SEM和EDS观察和分析了它们的表面形貌和成分,采用XRD表征了薄膜的组织结构,采用霍尔测试仪测量了薄膜的载流子浓度和霍尔迁移率.结果表明,Cu-In薄膜由In和Cu11In9两相组成,在不同的硒化温度下制备的CIS薄膜,均具有单一的黄铜矿CuInSe2相结构.随着硒化温度的升高,CIS薄膜的晶粒直径增大,当硒化温度达到550℃时,晶粒直径已接近于2 μm.硒化温度继续升高,晶粒之间出现孔洞和缝隙等缺陷.530℃的硒化温度下制得的弱p型CIS薄膜,最符合CuInSe2的化学计量比,最适于制备太阳能电池吸收层.     

硒源温度对CIGS薄膜结构和形貌的影响

采用中频交流磁控溅射方法，在Mo层上沉积了CuInGa（CIG）预制膜，采用固态硒化法制备获得了Cu（In1-xGax）Se2（CIGS）吸收层薄膜，考察了硒源温度对CIGS薄膜结构和形貌的影响。采用SEM和EDS观察和分析了薄膜的表面形貌和成分，采用XRD表征了薄膜的组织结构。结果表明，在不同的硒源温度下制备的CIGS薄膜，均为黄铜矿相结构，薄膜具有（112）面的择优取向。当硒源温度为575℃、580℃和585℃时，CIGS薄膜表面结构疏松，多孔隙；当硒源温度为590℃、595℃和600℃时，CIGS薄膜结构致密，表面平整。当硒源温度为600℃时，Cu、In和Ga原子含量处于制备弱P型CIGS吸收层薄膜的理想范围。     

周期性前驱体的预硫化处理对Cu2ZnSnS4薄膜的影响EI北大核心CSCD

Cu2ZnSnS4薄膜具有组成元素来源丰富、吸收系数高等优点,是理想的薄膜太阳能电池吸收层材料。采用磁控溅射法沉积周期性金属叠层前驱体,再进行两步硫化处理制备出Cu2ZnSnS4薄膜,分析第一步硫化(即预硫化)对Cu2ZnSnS4薄膜特性的影响。结果表明,预硫化处理可促进前驱体的硫化反应。经过预硫化处理的Cu2ZnSnS4薄膜的结晶度优于未进行预硫化处理的Cu2ZnSnS4薄膜。当预硫化温度为350℃时,增加预硫化时间有利于硫化反应的进行,并抑制Sn元素损失,但过长的预硫化时间导致Cu2ZnSnS4薄膜中易出现二次相,影响薄膜的特性。预硫化温度350℃、预硫化时间10 min的Cu2ZnSnS4薄膜结晶度最优,薄膜组分具有贫Cu、富Zn特性,且薄膜表面无孔隙。     

PdSe2半导体薄膜的真空硒化法制备研究

PdSe2薄膜主要通过机械剥离法和气相沉积法制得,本研究采用一种简单有效的可在SiO2/Si衬底上制备PdSe2薄膜的方法.通过高真空磁控溅射技术在SiO2/Si衬底上沉积一层Pd金属薄膜,将Pd金属薄膜与Se粉封在高真空的石英管中并在一定的温度下进行硒化,获得PdSe2薄膜.根据截面高分辨透射电镜(HRTEM)照片可...     

The optical and structural properties of polycrystalline Cu(In,Ga)(Se,S)2 absorber thin films

The pentenary compound semiconductor Cu(In,Ga)(Se,S)₂ is one of the most attractive materials for high-efficiency solar cells due to its tunable band gap to match well the solar spectrum. In this study, semiconducting Cu(In,Ga)(Se,S)₂ thin films were prepared by a classical two-step growth process, which involves the selenization and/or sulfurization of In/Cu–Ga precursor. During the precursor formation step metallic In/Cu–Ga alloys were deposited onto the Mo-coated soda-lime glass substrates by DC magnetron sputter process. The respective precursors were subsequently reacted with H₂Se and/or H₂S gasses, at elevated temperatures. By optimizing the selenization parameters, such as the gas concentrations, reaction time, reaction temperature, and the flow of H₂Se and H₂S, high quality, single phase pentenary films were obtained. The gallium and sulfur diffusion behaviors were found to depend strongly on the selenization/sulfurization profile. The surface morphology, phase structure, and composition of the layers were analyzed by scanning electron microscope, atomic force microscopy, X-ray diffraction, and electron diffraction spectroscopy. Photoluminescence measurements were performed to examine the optical properties of the films.     

N掺杂Cu2O薄膜的低温沉积及快速热退火研究

采用氧化亚铜(Cu_2O)陶瓷靶,利用射频磁控溅射沉积法在氮气和氩气的混合气氛下制备了N掺杂Cu_2O(Cu_2O∶N)薄膜,并在N_2气氛下对薄膜进行了快速热退火处理,研究了N_2流量和退火温度对Cu_2O∶N薄膜的生长行为、物相结构、表面形貌及光电性能的影响。结果显示,在衬底温度300℃、N_2流量12sccm条件下生长的薄膜为纯相Cu_2O薄膜;在N_2气氛下对预沉积薄膜进行快速热退火处理不影响薄膜的物相结构,薄膜的结晶质量随退火温度(450℃)的升高而显著改善;快速热退火处理能改善薄膜的结晶质量和缺陷,降低光生载流子的散射,增强载流子的传输,预沉积Cu_2O∶N薄膜经400℃退火处理后展示出较好的电性能,薄膜的霍尔迁移率(μ)为27.8cm~2·V~(-1)·s~(-1)、电阻率(ρ)为2.47×10~3Ω·cm。研究表明低温溅射沉积和快速热退火处理能有效改善Cu_2O∶N薄膜的光电性能。     

Effect of sulfurization in hydrogen sulfide on the properties of Cu(In,Ga)Se2 thin-film absorbers

In this research Cu(In,Ga)Se₂ thin films were sulfurized in H₂S–Ar gas mixture with processing temperatures ranging from 400 to 550 °C and time ranging from 10 to 60 min. The change in crystal phases, microstructure and chemical compositions of the absorber layers after sulfurization were investigated by X-ray diffraction, high resolution TEM, scanning electron microscopy, Raman scattering spectrum, energy dispersive X-ray spectrometer. In the process of sulfurization, the crystallinity and sulfurization degree of the Cu(In,Ga)(S,Se)₂ films depend strongly on the sulfurization temperature. The ‘Cu–Au’ phase was found for samples grown at low sulfurization temperature and transformed to chalcopyrite-type phase at high sulfurization temperature. The Se–S vibration mode of Cu(S,Se) alloy was also observed in the Raman spectra.     

X-ray and Magnetoresistance Measurements of Electrodeposited Cu-Co Granular Films

Granular CoxCu1-x alloy films were prepared by electrodeposition at room temperature directly onto semiconducting Si substrate. X-ray diffraction (XRD) revealed that the as-deposited films formed single phase metastable fcc alloy structure. The fcc lattice parameter αwas found to decrease linearly with increasing Co concentration x in the studied range. The giant magnetoresistance (GMR) of the films was improved after annealing. Pure Co fcc diffraction peaks were observed in the diffractogram of the annealed sample, indicating phase separation occurred upon annealing. The optimal annealing temperature was 450℃. The maximum of magnetoresistance (MR) ratio 8.21% was obtained for the Co20Cu80 thin film after annealing at 450℃for 1 h. The saturation field decreased upon annealing in the MR curves of Co20Cu80 film.     

氮气退火对氧化镍薄膜光电特性的影响

利用磁控溅射法,在K9玻璃基底上沉积氧化镍(NiO)薄膜。采用不同温度对氧化镍薄膜进行氮气退火,使用UV-1700型分光光度计、JSM-6490LV型扫描电子显微镜、四探针电阻计等分析退火后氧化镍薄膜性能的变化。实验结果表明,500℃退火范围内,氧化镍薄膜的透过率随退火温度的升高明显增加,400℃时透过率达到最大在80%以上,且光学带隙最小,结晶度较高,薄膜成分变化较小,更适于太阳电池窗口层的应用研究。     

Preparation of Zn(In)Se films from alloyed precursors

Single-phase cubic Zn(In)Se thin film growth by Se vapor selenization of Zn(In) alloy precursors films is described. Depositing the Zn(In) precursor film at higher substrate temperatures changes the In/Zn composition and also yields highly crystalline Zn(In)Se films. The In/Zn ratio in the selenized film is higher in comparison to that of the precursor due to differential selenization kinetics and the complex In-Se and Zn-Se reaction chemistry. The resistivity of the Zn(In)Se film depends on the In/Zn ratio. Initially, the resistivity increases with increased indium incorporation due to increased defect concentration and then decreases at higher In/Zn ratios because of lower grain-boundary effects and reduced trap density owing to improvement in film crystallinity. Treatment with vapor-phase Zn compensates for Zn vacancies in the film, reduces electrically inactive defects, and increases doping efficiency, thereby lowering the resistivities to ∼1 Ω cm. Hot-probe and thermoelectric power measurements show that all low resistive ZnSe films are n-type.     

Influence of GaSe deposition temperature on the structural properties and in-depth compositional features of two-step grown Cu(In,Ga)Se2 thin films

In this study, Cu(In,Ga)Se₂ thin films were prepared by a classical two-stage growth process, which involved the selenization of thermally evaporated InSe/Cu/GaSe precursors. During the precursor-formation step the InSe and Cu were always deposited at 200 °C, while the GaSe layers were deposited at temperatures between 200 °C and 400 °C. The respective precursors were simultaneously selenized under identical conditions in elemental Se vapor. In cases where the GaSe layers were deposited at low temperatures around 200 °C, X-ray fluorescence (XRF) analysis revealed a large variation in element concentration with sample depth after selenization. In correspondence, X-ray diffraction (XRD) studies revealed the presence of separate CuInSe₂ and CuGaSe₂ phases in these specific samples. Optimum structural properties were obtained when the GaSe films were deposited at 300 °C, followed by selenization. In general, these films were uniform and dense and XRD studies revealed single-phase Cu(In,Ga)Se₂ material. Even more importantly, XRF analysis revealed a remarkable improvement in in-depth compositional uniformity when the GaSe films were deposited at or above 300 °C. An increase in GaSe deposition temperature to 400 °C, however, resulted in a deterioration in the structural features of the Cu(In,Ga)Se₂ thin films. In contradiction with other reports, these results indicated that the in-depth composition uniformity and especially the Ga diffusion profile in two-step grown Cu(In,Ga)Se₂ thin films can be controlled. The crucial factor influencing the depth profile of these films is the GaSe deposition temperature during the precursor formation step.     

Non-toxic selenization using thermal annealing for CuGa/In bi-layer precursors deposited by sputtering

Cu(In_xGa_1?x)Se₂ (CIGS) thin films were produced using a two-step sputtering process consisting of precursor formation and selenization. In the first stage, we prepared Cu_0.75Ga_0.25/In bi-layer precursors by direct current sputtering on Mo/soda-lime glass substrates. In the second stage, the stacked precursors were selenized using non-toxic Se pellets in a graphite box in which the temperature was controlled at 475–680 °C during rapid thermal annealing. We investigated the effect of thermal annealing temperature on Ga distribution and the crystallinity of the Cu(In_xGa_1?x)Se₂ films. Thermal annealing significantly affected the distribution of Ga atoms. At low temperatures, segregation of Ga atoms into the CIGS/Mo interface and an absence of Ga content on the surface were observed. In addition, a phase-separated CuInSe₂/CuGaSe₂ structure and incomplete selenization phases were observed. At high temperatures, CIGS films were formed with the proper distribution of Ga content.