Article
Materials Science, Multidisciplinary
Yuandong Liu, Yangzheng Li, Junlei Tang, Wenfeng Zhang, Bing Lin, Yaqiong Cao
Summary: In this study, a Cu(In,Ga)Se2 (CIGS) quaternary target containing NaF was used to fabricate thin-film solar-cell devices on polyimide (PI) foils. Multiple metal layers were prepared on both sides of the PI substrate to improve the efficiency of the CIGS cells, and the annealing process was investigated. The Ti/Cr/Mo sandwich structure on PI foils improved the thermal budget as it withstands higher annealing temperature (520 degrees C) for a shorter duration (5 min). A 2-step annealing process and a high-temperature selenization process were used to enhance the integrity and elemental distribution of the absorber film. The fabricated CIGS cells achieved an average power conversion efficiency of 13.6%.
Article
Materials Science, Multidisciplinary
Stephan J. Heise, Hippolyte Hirwa, Marko Stoelzel, Thomas Dalibor, Joerg Ohland
Summary: This study investigates the origin of the N1 signature in Cu(In,Ga)(S,Se)(2) devices by systematically varying the individual layers of the cell stack. The results suggest that the N1 signature is caused by a transport barrier in the buffer/absorber region.
Article
Engineering, Environmental
Huyen Tran, Syed Dildar Haider Naqvi, Kihwan Kim, Ahreum Lee, Seungju Oh, Yasir Siddique, Asmat Ullah, Shah Syed Fawad Ali, Minwoo Park, Sungjun Hong, Sejin Ahn, Jihye Gwak, Inyoung Jeong
Summary: A facile fabrication strategy of highly efficient and stable wide-bandgap perovskites (PVSKs) was demonstrated through an organic halide surface treatment. The surface post-treatment resulted in the complete conversion of PVSK crystallinity, eliminating segregated secondary phases and reducing unreacted PbI2. The reconstructed PVSK showed enhanced photovoltaic performance and high stability, achieving a power conversion efficiency of 24.5% in a tandem device.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Liting Tang, Xiaomin Wang, Xinxing Liu, Junjun Zhang, Shaoying Wang, Yuqi Zhao, Junbo Gong, Jianmin Li, Xudong Xiao
Summary: In this paper, a method for passivating interface and grain boundary defects in perovskite solar cells (PSCs) is proposed by dissolving the passivation materials in mixed solvents of IPA and toluene. The performance parameters of PSCs are improved, resulting in an increased power conversion efficiency (PCE). Moreover, a 4-terminal perovskite/CIGS tandem device is achieved with a high PCE, demonstrating the potential of the mixed solvent passivation strategy in enhancing the efficiency and stability of PSCs.
Article
Chemistry, Analytical
Dong-Seok Shin, Tae-Ho Kim, Jeong-Eun Rah, Dohyeon Kim, Hye Jeong Yang, Se Byeong Lee, Young Kyung Lim, Jonghwi Jeong, Haksoo Kim, Dongho Shin, Jaeman Son
Summary: This study proposes a dose measurement system based on a flexible CIGS solar cell, demonstrating good dosimetric characteristics such as dose linearity, rate and energy independence, and field size output.
Article
Chemistry, Physical
C. B. Isabela, Ricardo A. Marques Lameirinhas, Joao Paulo N. Torres, Carlos A. F. Fernandes
Summary: Thin-film modules are becoming popular in the photovoltaic market due to their competitive cost compared to traditional crystalline silicon modules. Among them, CuIn(1-x)GaxSe2 (CIGS) cells are leading the expansion in the market due to their low temperature coefficient and ability to absorb UV and IR radiation. Comparative studies among different photovoltaic technologies, including theoretical comparisons, simulations, and experimental tests, show that CIGS performance is approaching that of silicon cells.
SUSTAINABLE ENERGY & FUELS
(2021)
Article
Materials Science, Multidisciplinary
Alice Debot, Van Ben Chu, Damilola Adeleye, Jerome Guillot, Didier Arl, Michele Melchiorre, Phillip J. Dale
Summary: In this study, an environmentally friendly inkjet-printed indium sulfide (In2S3) buffer layer was developed using benign chemistry and processing conditions. A pre-synthesized indium-thiourea compound was dissolved in a mixture of water and ethanol, and then inkjet printed onto a Cu(In,Ga)(S,Se)(2) absorber. The resulting buffer layer showed good coverage on the surface of the absorber layer, leading to improved device performance.
Article
Energy & Fuels
Deewakar Poudel, Benjamin Belfore, Tasnuva Ashrafee, Elizabeth Palmiotti, Shankar Karki, Grace Rajan, Thomas Lepetit, Angus Rockett, Sylvain Marsillac
Summary: Cu(In,Ga)Se-2 thin films and devices were fabricated using a modified three-stage process, with a copper chloride vapor treatment introduced to enhance film properties. After recrystallization, films showed larger grains, but not all parameters of the solar cells were enhanced, resulting in only a 15% increase in device efficiency.
Article
Energy & Fuels
Elizabeth Palmiotti, Sylvain Marsillac, Angus Rockett
Summary: This study compares and evaluates the metal halide treatments of CdTe films and CIGS, finding that CdTe films have lower manufacturing costs, while CIGS requires higher temperatures and lower rates to achieve high efficiency. Silver halides are beneficial for the transport of all species, while compounds containing gallium and indium may pose some issues. Copper compounds have low vapor pressure but exhibit high mobility in CIGS.
PROGRESS IN PHOTOVOLTAICS
(2023)
Article
Chemistry, Physical
Deewakar Poudel, Benjamin Belfore, Tasnuva Ashrafee, Shankar Karki, Grace Rajan, Angus Rockett, Sylvain Marsillac
Summary: Post-deposition treatments with indium bromide vapor at 400 and 500 degrees Celsius lead to larger grains and higher conductivity in Cu(In,Ga)Se-2 thin films compared to simple annealing under selenium. These properties are attributed to a modification of elemental profiles, particularly for gallium and sodium.
Article
Materials Science, Multidisciplinary
David Stock, Nikolaus Weinberger, Florian Ruske, Leander Haug, Martina Harnisch, Roman Lackner
Summary: This study describes the development and characterization of titanium dioxide thin films using direct current magnetron sputtering from ceramic targets mixed with metallic titanium particles. The suitability of these films as a buffer layer in CIGSe based solar cells is evaluated. The research investigates the potential to modify the electro-optical properties of TiO2 thin films by controlling the concentration of defects, such as oxygen vacancies. The presence of oxygen in the plasma during the sputter deposition process has a crucial impact on the electron transport mechanism in the devices. The results indicate that the harmful effect of oxygen restricts the possibilities to modify the material properties of the TiO2 layers, and further optimization on both sides of the absorber-buffer interface is necessary for improved cell performance.
Article
Materials Science, Multidisciplinary
F. Giesl, C. Schubbert, P. Eraerds, S. Heise, R. Lechner, T. Dalibor, J. Parisi
Summary: In this study, the electrical transport across the valence band injection barrier at the interface between the Cu(In,Ga)(S,Se)2 absorber layer and the Mo(Se,S)2 layer was investigated. The sulfur contents were varied to study their effects on the injection barrier. Experimental measurements and device simulations were used to determine the valence band offsets and understand the mechanisms at play at the interface.
Article
Radiology, Nuclear Medicine & Medical Imaging
Dong-Seok Shin, Tae-Ho Kim, Jeong-Eun Rah, Se Byeong Lee, Young Kyung Lim, Jonghwi Jeong, Haksoo Kim, Dongho Shin, Jaeman Son
Summary: The purpose of this study is to propose a novel flexible skin dosimeter based on a thin-film copper indium gallium selenide (CIGS) solar cell and evaluate its dosimetric characteristics. The CIGS solar cell dosimeter showed good performance in terms of dose measurement linearity, sampling rate effect, dose rate dependence, energy dependence, and field size output factor. It is a low-cost dosimeter that can be easily customized, providing advantages over other dosimeters.
Article
Materials Science, Multidisciplinary
Mariana Montoya-Gomez, Stefan Paetel, Wolfram Hempel, Ana Kanevce, Theresa Magorian Friedlmeier, Dimitrios Hariskos
Summary: Cu(In,Ga)Se2-based solar cells achieve highest efficiencies up to 23.4% by using solution-grown Zn(O,S) as the buffer layer. We test the impact of oxidative and reductive additives on the growth rate of Zn(O,S) and find that both additives can significantly increase the growth rate and reduce the consumption of reactants without compromising the performance of the solar cells.
Article
Engineering, Electrical & Electronic
Arelis Ledesma-Juarez, A. M. Fernandez
Summary: Cu(In, Ga)Se-2 thin films have desirable optoelectronic properties for applications in solar cells. Commercialization has been limited by costly vacuum deposition methods, but electrodeposition offers a cost-effective alternative. This study investigates the use of different metal salts and voltages to produce CIGS thin films by co-electrodeposition technique, aiming to optimize the stoichiometry for efficient thin film solar cells.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Materials Science, Multidisciplinary
Curtis Walkons, Mohsen Jahandardoost, Theresa M. Friedlmeier, Wolfram Hempel, Stefan Paetel, Marco Nardone, Benedikt Ursprung, Edward S. Barnard, Kyoung E. Kweon, Vincenzo Lordi, Shubhra Bansal
Summary: The study demonstrates significant effects of Na and RbF alkali treatment on the performance of CdS/Cu(In,Ga)Se-2 solar cells, with low-Na devices exhibiting higher bandgaps and steady-state carrier densities, and devices with RbF post-deposition treatment showing improvements in net doping density and efficiency. Both heat- and light-soaking processes result in changes in Na and oxygen concentrations in CIGS, while the atomic concentration profiles in CIGS stabilize significantly with the addition of RbF-PDT.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Wolfram Witte, Wolfram Hempel, Stefan Paetel, Richard Menner, Dimitrios Hariskos
Summary: Sputtered InxSy on CIGS with RbF treatment can achieve good solar cell efficiency in an all-dry process, while controlling the deposition temperature and post-annealing steps of InxSy are key for improving efficiency.
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Mohsen Jahandardoost, Marco Nardone, Theresa Magorian Friedlmeier, Curtis Walkons, Shubhra Bansal
Summary: The degradation of RbF post-deposition-treated (PDT) CIGS solar cells under heat/light/bias stress is evaluated for two different buffers, CdS and Zn(O,S). It was found that CdS buffer devices are relatively stable while Zn(O,S) buffer devices show significant efficiency loss. Device models suggest that increased recombination at the CIGS/Zn(O,S) interface and near interface doping contribute to the degradation in Zn(O,S) buffer devices.
JOURNAL OF MATERIALS RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Aniela Czudek, Aleksander Urbaniak, Alexander Eslam, Roland Wuerz, Malgorzata Igalson
Summary: The postdeposition treatment with potassium fluoride (KF-PDT) affects the bulk properties of CIGSe solar cells, not just the surface of the absorber. Both alkali metals impact the electrical properties of the entire CIGSe layer, with effects on grain boundary properties highlighted by changes in electrical conductivity and doping levels. Persistent photoconductivity is correlated with relaxed conductivity in both NaF- and KF-treated samples, indicating potential barriers at grain boundaries limiting electrical transport in CIGSe.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Alexander Eslam, Roland Wuerz, Dirk Hauschild, Lothar Weinhardt, Wolfram Hempel, Michael Powalla, Clemens Heske
Summary: The influence of post-deposition treatments with NaF and KF on Cu(In,Ga)Se2 thin-film solar cell absorbers was studied at different substrate temperatures. Both treatments significantly improved cell efficiency, with the highest conversion efficiency achieved with NaF PDT at a high temperature. KF treatment led to reduced efficiency at low temperature due to the formation of a Cu-Se secondary phase at the CIGSe surface.
Article
Energy & Fuels
Mario Zinsser, Moritz Loy, Tim Helder, Andreas Bauer, Theresa Magorian Friedlmeier, Michael Powalla
Summary: This study presents a novel quasi-3D finite element method tool to simulate the electrical influences between different layers in thin-film photovoltaic devices. It provides insights into the physical processes within solar cell devices and can predict characteristic I-V curves and power conversion efficiency.
IEEE JOURNAL OF PHOTOVOLTAICS
(2022)
Article
Materials Science, Multidisciplinary
Wolfram Witte, Wolfram Hempel, Stefan Paetel, Richard Menner, Dimitrios Hariskos
Summary: This study explores the use of gallium oxide as a substitute material in the buffer or HR layers of CIGS thin-film solar cells and investigates its impact on device performance. Through a series of experiments and treatment methods, the efficiency of the cells was successfully improved.
JOURNAL OF MATERIALS RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Mahdi Malekshahi Byranvand, Tim Kodalle, Weiwei Zuo, Theresa Magorian Friedlmeier, Maged Abdelsamie, Kootak Hong, Waqas Zia, Shama Perween, Oliver Clemens, Carolin M. Sutter-Fella, Michael Saliba
Summary: This article reports a simple method to control the crystallization of inorganic perovskite films under thermal gradient and antisolvent-free conditions, resulting in high-quality perovskite films with excellent performance and thermal stability.
Article
Energy & Fuels
Tim Helder, Ana Kanevce, Mario Zinsser, Rico Gutzler, Stefan Paetel, Wolfram Hempel, Theresa Magorian Friedlmeier, Michael Powalla
Summary: This study investigates the effect of rubidium-fluoride (RbF) postdeposition treatment (PDT) on the performance and physical properties of (Ag,Cu)(In,Ga)Se-2 (ACIGS) solar cells. The results show that the efficiency of ACIGS devices is reduced by the PDT process, unlike observed for Cu(In,Ga)Se-2 (CIGS) absorber. The amount of rubidium strongly influences the efficiency and the doping mechanism of the ACIGS absorber.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Chemistry, Physical
Wolfram Hempel, Theresa Magorian Friedlmeier
Summary: The thin-film photovoltaic technology based on CIGS has achieved high conversion efficiencies. To accurately measure the gallium gradient and alkali metals in CIGS, ToF-SIMS is suitable but its spatial resolution is influenced by the measurement parameters. Small copper aggregations and Cu lamellas can affect the measurements due to preferential sputtering. Cooling with liquid nitrogen and new ion sources can minimize these effects.
SURFACE AND INTERFACE ANALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Ahmed Farag, Paul Fassl, Hang Hu, Thomas Feeney, Aina Quintilla, Marco A. Ruiz-Preciado, Wolfram Hempel, Dominik Bagrowski, Philipp Noack, Bianca Wattenberg, Torsten Dippell, Ulrich W. Paetzold
Summary: The recent development of solution-processed perovskite thin films over micrometer-sized textured silicon bottom solar cells enables tandem solar cells with power conversion efficiencies > 30%. This study provides a practical guideline to discriminate and address the voltage losses at the interfaces as well as in the bulk of solution-processed double cation perovskite thin films using photoluminescence quantum yield measurements. The guideline will be beneficial for scientists working on randomly textured surfaces and provides a deeper understanding on this timely research topic.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Mariana Montoya-Gomez, Stefan Paetel, Wolfram Hempel, Ana Kanevce, Theresa Magorian Friedlmeier, Dimitrios Hariskos
Summary: Cu(In,Ga)Se2-based solar cells achieve highest efficiencies up to 23.4% by using solution-grown Zn(O,S) as the buffer layer. We test the impact of oxidative and reductive additives on the growth rate of Zn(O,S) and find that both additives can significantly increase the growth rate and reduce the consumption of reactants without compromising the performance of the solar cells.
Article
Physics, Applied
Ana Kanevce, Stephanie Essig, Stefan Paetel, Wolfram Hempel, Dimitrios Hariskos, Theresa Magorian Friedlmeier
Summary: Partial substitution of Cu by Ag in CIGS solar cells allows lower temperature growth while maintaining high performance. Analysis of ACIGS samples with varying Ag content reveals changes in electrical and material properties, including decreased carrier density, increased grain size, and reduced back grading. Although cells with higher Ag contents have slightly lower conversion efficiencies, they have smoother absorber surfaces, which is advantageous for tandem applications.
Article
Physics, Applied
Tim Helder, Ana Kanevce, Andreas Bauer, Mario Zinsser, Stefan Paetel, Theresa Magorian Friedlmeier, Michael Powalla
Summary: This study performed DLTS measurements on CIGS solar cells from an inline co-evaporation system, focusing on the effect of RbF-PDT on defects in the CIGS absorber layer. Different traps were identified and their properties were calculated. The results were verified using different evaluation methods, showing a significant reduction in density of a minority trap after the alkali treatment, while a majority trap remained unaffected.
