Na掺入制备不锈钢衬底CIGS太阳电池

以轻质柔性不锈钢材料为衬底,利用共蒸发法制备较高质量的四元化合物Cu(In,Ga)Se2薄膜,在沉积CIGS薄膜前沉积一定厚度的NaF预置层,使得所制备的CIGS薄膜含有适量浓度的Na,并获得了10.06%的转换效率.利用X射线衍射仪和X射线荧光光谱仪分别测量了所制备薄膜的晶相和组分,利用扫描电子显微镜分析了不锈钢衬底CIGS太阳电池的断面形貌,最后分析了NaF的掺入对CIGS太阳电池的影响.     

In2Se3薄膜生长及结晶择优取向的影响因素研究

(In,Ga)2Se3薄膜的生长结晶性的好坏直接影响着在其基础上化合生长的Cu(In,Ga)Se2(CIGS)薄膜以及CIGS太阳电池器件的性能.实验就多源共蒸发制备In2Se3预制层工艺中3个主要条件,即衬底材质、Se源温度、衬底温度进行研究.分析讨论上述3种因素对In2Se3薄膜的结晶生长和择优取向生长的影响.发现:在Mo/苏打石灰玻璃(Mo/SLG)衬底上生长,Se源温度在270℃以上或衬底温度为380～400℃的较高温度时,制备的In2Se3预制层是单一晶相的In2Se3,其x射线衍射峰是以(110)和(300)峰为择优取向.反之,生长在苏打石灰玻璃(SLG)衬底上,Se源温度为230℃以下或衬底温度为较低温度300℃时,In2Se3预制层结晶质量较差,其X射线衍射峰则多以In2Se3(006)衍射峰为择优取向.     

硒蒸气硒化法制备CIGS薄膜的影响因子(Ⅰ)氩气流量对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CulEnGa(cIc)预制膜.以Ar为载气,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Ar流量对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份,采用XRD表征了薄膜的组织结构.结果表明,在不同Ar流量下制备的CIGS薄膜均具有单一的黄铜矿相结构,薄膜具有(112)面的择优取向.随着Ar流量的增大,CIGS薄膜晶粒直径增大.当Ar流量为0.20m3/h时,薄膜的孔隙最少.当Ar流量达到0.40m3/h时,薄膜晶粒出现明显的柱状生长.当Ar流量为0.10、0.20和0.30 m3/h时,所制得的CIGS薄膜的Cu、In、Ga原子含量比,处于弱p型的理想范围.     

薄膜太阳电池系列讲座(8) CIGS薄膜太阳电池(下)

③柔性CIGS电池的卷-卷(Roll-to-Roll)制备工艺CIGS薄膜电池制备在柔性衬底上,使其可能采用卷绕式(Roll-to-Roll)生产工艺。几百米甚至上千米长的电池一次完成[9],卷对卷工艺可降低设备造价和占地面积,同时有效提高生产效率。卷对卷工艺设备局部示意图如图16所示。在CIGS薄膜电池工艺流程中,在分切成外联要求的单个电池     

硒蒸气硒化法制备CIGS薄膜的影响因子（I）氩气流量对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。以Ar为载气,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Ar流量对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份,采用XRD表征了薄膜的组织结构。结果表明,在不同血流量下制备的CIGS薄膜均具有单一的黄铜矿相结构,薄膜具有（112）面的择优取向。随着Ar流量的增大,CIGS薄膜晶粒直径增大。当舡流量为0．20m^3／h时,薄膜的孔隙最少。当Ar流量达到0．40m^3/h时,薄膜晶粒出现明显的柱状生长。当心流量为0．10、0．20和0．30m^3/h时,所制得的CIGS薄膜的Cu、In、Ga原子含量比,处于弱P型的理想范围。     

CIGS薄膜太阳电池(下)

③柔性CIGS电池的卷一卷(Roll-to-Roll)制备工艺CIGS薄膜电池制备在柔性衬底上,使其可能采用卷绕式(Roll-to-Roll)生产工艺.几百米甚至上千米长的电池一次完成[9],卷对卷工艺可降低设备造价和占地面积,同时有效提高生产效率.卷对卷工艺设备局部示意图如图16所示.在CIGS薄膜电池工艺流程中,在分切成外联要求的单个电池前,都可采用卷对卷工艺.     

硒蒸气硒化法制备CIGS薄膜的影响因子（II）预制膜对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层上沉积了多层和双层CuInGa（CIG）预制膜,采用固态硒化法制备获得了Cu（In1-xGax）曳（CIGS）吸收层薄膜,考察了预制膜对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,CIG多层预制膜由Cu11In9、CuIn和In相组成,CIG双层预制膜由Cu11In9、CuIn、In和CuGa相组成。通过硒化CIG双层和多层预制膜,所获得的CIGS薄膜均为黄铜矿相结构,薄膜具有（112）面的择优取向。当硒化时间为17min时,通过硒化CIG双层预制膜所获得的CIGS薄膜出现了上层致密,下层疏松的结构．延长硒化时间为25min．CIGS薄膜蛮得致密。     

硒蒸气硒化法制备CIGS薄膜的影响因子(Ⅱ)预制膜对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层上沉积了多层和双层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,考察了预制膜对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,CIG多层预制膜由Cu11 In9、CuIn和In相组成,CIG双层预制膜由Cu11 In9、CuIn、In和CuGa相组成.通过硒化CIG双层和多层预制膜,所获得的CIGS薄膜均为黄铜矿相结构,薄膜具有(112)面的择优取向.当硒化时间为17min时,通过硒化CIG双层预制膜所获得的CIGS薄膜出现了上层致密,下层疏松的结构,延长硒化时间为25min,CIGS薄膜变得致密.     

效率为12.1%的Cu(In,Ga)Se2薄膜太阳电池

利用共蒸发的三步法制备了较高质量的四元化合物Cu(In，Ga)Se2(CIGS)薄膜，并采用Mo／CIGS／CdS／ZnO结构为基础做出转换效率超过10％的薄膜太阳电池，其最高转换效率达到12．1％(测试条件为：AM1．5，Global 1000W／m^2)。通过与国际最高水平的CIGS太阳电池各参数的比较，分析了我们所制备的CIGS太阳电池在工艺和物理方面存在的问题。     

CIS/CIGS薄膜的制备技术与其生长机理研究

多晶CuInSe2或称Cu(In,Ga)Se2(简称GIS或CIGS)材料在薄膜太阳电池中具有重要的应用.GIS/CIGS的制备方法很多,制备方法不同,CIS的形成机理也不相同,本文对几种典型的制备方法的形成机理做了简要的讨论,并应用XRD、DSC手段,对于金属预制层后硒化法的薄膜的形成机理进行了研究.实验结果显示,溅射法制备的预制层有5种相同时存在,衬底温度升高到220℃,Se熔化后,薄膜中化学反应剧烈,有三元相产生;至350℃,三元相转化成了黄铜矿CuInSe2.     

Cu(In,Ga)Se2 solar cells on stainless steel substrates covered with insulating layers

We have developed the flexible Cu(In,Ga)Se₂ (CIGS) solar cells on the stainless steel substrates with the insulating layer for the fabrication of the integrated module. The CIGS films have strong adhesion to the Mo films with insulating layers. An efficiency of 12.3% was achieved by the flexible CIGS solar cell with a structure of ITO/ZnO/CdS/CIGS/Mo/SiO₂/stainless steel. The insertion of the SiO₂ insulating layer did not have an influence on the formation of the CIGS film and solar cell performances.     

Fabrication of Cu(In,Ga)Se2 thin films solar cell by selenization process with Se vapor

CIGS films were prepared on Mo-coated glass by sputtering and selenization processes. The metallic precursors were selenized under higher pressure in selenium vapor instead of H₂Se. In order to improve the performance of CIGS thin film solar cells, the morphologies of CIGS thin films were studied carefully by various temperature profiles. The relationship between temperature decrease rate and fill factor (FF) of solar cells was investigated thoroughly. On the other hand the value of open circuit voltage (V_oc) was improved by increasing the gallium content near the surface of CIGS thin film. A glass/Mo/CIGS/CdS/ZnO cell was fabricated and the conversion efficiency of 9.4% was obtained without antireflective film.     

Novel device structure for Cu(In,Ga)Se2 thin film solar cells using transparent conducting oxide back and front contacts

Cu(In_1−xGa_x)Se₂ (CIGS)-based thin film solar cells fabricated using transparent conducting oxide (TCO) front and back contacts were investigated. The cell performance of substrate-type CIGS devices using TCO back contacts was almost the same as that of conventional CIGS solar cells with metallic Mo back contacts when the CIGS deposition temperatures were below 500 °C for SnO₂:F and 520 °C for ITO. CIGS thin film solar cells fabricated with ITO back contacts had an efficiency of 15.2% without anti-reflection coatings. However, the cell performance deteriorated at deposition temperatures above 520 °C. This is attributed to the increased resistivity of the TCO’s due to the removal of fluorine from SnO₂ or undesirable formation of a Ga₂O₃ thin layer at the CIGS/ITO interface. The formation of Ga₂O₃ was eliminated by inserting an intermediate layer such as Mo between ITO and CIGS. Furthermore, bifacial CIGS thin film solar cells were demonstrated as being one of the applications of semi-transparent CIGS devices. The cell performance of bifacial devices was improved by controlling the thickness of the CIGS absorber layer. Superstrate-type CIGS thin film solar cells with an efficiency of 12.8% were fabricated using a ZnO:Al front contact. Key techniques include the use of a graded band gap Cu(In,Ga)₃Se₅ phase absorber layer and a ZnO buffer layer along with the inclusion of Na₂S during CIGS deposition.     

Improved CIGS thin-film solar cells by surface sulfurization using In2S3 and sulfur vapor

Surface sulfurization of Cu(In,Ga)Se₂ (CIGS) thin films was carried out using two alternative techniques that do not utilize toxic H₂S gas; a sequential evaporation of In₂S₃ after CIGS deposition and the annealing of CIGS thin films in sulfur vapor. A Cu(In,Ga) (S,Se)₂ thin layer was grown on the surface of the CIGS thin film after sulfurization using In₂S₃, whereas this layer was not observed for CIGS thin films after sulfurization using sulfur vapor, although a trace quantity of S was confirmed by AES analysis. In spite of the difference in the surface modification techniques, the cell performance and process yield of the ZnO:Al/CdS/CIGS/Mo/glass thin-film solar cells were remarkably improved by using both surface sulfurization techniques.     

Cu(In,Ga)Se2 solar cells on stainless-steel substrates covered with ZnO diffusion barriers

ZnO layers were deposited as diffusion barriers by DC magnetron sputtering from a pure Zn target on stainless-steel substrates. It was found that the insertion layer of ZnO between Mo film and stainless-steel substrate had no influence on the orientation and composition of CIGS films, as identified by an X-ray diffractometer and X-ray fluorescence, respectively. However, ZnO diffusion barriers had strongly reduced the diffusion of Fe from stainless-steel substrates into the CIGS films, as investigated by secondary ion mass spectrometry. With such diffusion barriers, the efficiency, open-circuit voltage, and fill factor of CIGS solar cells all increased.     

Improved compositional flexibility of Cu(In,Ga)Se2-based thin film solar cells by sodium control technique

The effects of sodium on off-stoichiometric Cu(In,Ga)Se₂ (CIGS)-based thin films and solar cells were investigated. The CIGS-based films were deposited with intentionally incorporated Na₂Se on Mo-coated SiO_x/soda-lime glass substrates by a multi-step process. By sodium control technique high-efficiency ZnO : Al/CdS/CIGS solar cells with efficiencies of 10–13.5% range were obtained over an extremely wide Cu/(In + Ga) ratio range of 0.51–0.96, which has great merit for the large-area manufacturing process. The improved efficiency in the off-stoichiometric regions is mainly attributed to the increased acceptor concentration and the formation of the Cu(In,Ga)₃Se₅ phase films with p-type conductvity. A new type of solar cell with p-type Cu(In,Ga)₃Se₅ phase absorber materials is also suggested.     

Antireflection layer of ZnO nanorod embedded in PDMS film for enhancing omnidirectional photovoltaic performance of CIGS photovoltaic cell

In this study, a flexible polydimethylsiloxane (PDMS) ARL with embedded ZnO‐NRs was fabricated on the surfaces of Cu(In,Ga)Se₂ (CIGS) solar cells using the chemical solution method. Under the conditions of an AM1.5G solar spectrum, the application of the PDMS ARL of embedded ZnO‐NRs on the surface of a CIGS solar cell can effectively increase the conversion efficiency of the solar cell from 7.23% to 7.79%. In addition, broadband and omnidirectional light harvesting are important as the sun moves over time; therefore, omnidirectional anti‐reflection applications of various ARLs on CIGS photovoltaic cells were also studied.     

Formation of CuInSe2 and Cu(In,Ga)Se2 films by electrodeposition and vacuum annealing treatment

Polycrystalline thin films of CuInSe₂ and Cu(In,Ga)Se₂ (CIGS) were grown on both polished Mo substrates and Mo-coated glass substrates by one-step electrodeposition. All the as-deposited films have been annealed in vacuum at 450°C for a short time to improve the crystalline properties. The films have been characterized by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. The results indicate that the crystallization of the films was greatly improved after annealing. Further more, a CIGS film with 23 at% Ga was obtained.