Article
Energy & Fuels
S. Ma, R. Tong, X. Y. Wu, Z. P. Li, X. Y. Kong, W. Z. Shen
Summary: The study found that introducing SiNx films with a high refractive index and additive oxide films is beneficial in reducing the rear PID effect in bifacial p-Si PERCs. By using a combined structure of stack films as the rear passivation layer, both front-side and rear-side efficiency can be improved significantly, while reducing the power loss associated with rear PID.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Review
Chemistry, Physical
Jiakai Zhou, Qian Huang, Yi Ding, Guofu Hou, Ying Zhao
Summary: The pursuit of high energy conversion efficiency is driving the electricity market from renewable energies, with passivating contacts and tandem technologies identified as critical concepts for achieving high-efficiency Si-based solar cells. Passivating contacts are essential to overcome recombination losses, while combining Si with a high-bandgap tandem partner shows promise for surpassing the single junction Shockley-Queisser limit in solar cell efficiency.
Article
Chemistry, Physical
Ching-Hui Hsu, Da-Yao Lao, Likarn Wang
Summary: In this study, AlOx passivation layers on the rear sides of silicon PERC solar cells are formed by thermally oxidizing 3 nm-thick aluminum films. The oxidation process is conducted in a furnace full of oxygen at 400 degrees C for 10 minutes, followed by annealing at 700 degrees C for 3 minutes and then stacking SiNx films on the back surfaces. A second annealing process is done at 400 degrees C for 10 minutes to repair the defects resulting from ion bombardment on the passivation layer. With the thermal oxidation method, an AlOx passivation layer with a negative charge density of -3.21 x 10(12) cm(-2) was confirmed for an annealed sample, compared to -6.17 x 10(11) cm(-2) for an unannealed sample.
INTERNATIONAL JOURNAL OF PHOTOENERGY
(2023)
Article
Computer Science, Information Systems
S. Banerjee, S. S. A. Askari, M. K. Das
Summary: A device simulation model is developed to study the effects of rear contact coverage and fixed charge density dependent field-effect passivation on the performance of p-Si solar cell. The simulation considers hetero-interface physics related to metal-semiconductor, metal-oxide-semiconductor junctions and interface recombination, and the results are verified with experimental data. The analysis shows that the efficiency of the solar cell can be substantially enhanced by controlling parameters and suitable choice of design parameters and doping concentration in the emitter and absorber, as well as the oxide layer thickness.
Article
Energy & Fuels
Lilan Wen, Lei Zhao, Guanghong Wang, Xiaojie Jia, Xiaohua Xu, Shiyu Qu, Xiaotong Li, Xianyang Zhang, Ke Xin, Jihong Xiao, Wenjing Wang
Summary: The trilayer a-SiOx:H(i) stacked passivation structure was designed for SHJ solar cells on n-type c-Si wafer to improve their fill factor (FF). By depositing a-SiOx:H(i) layers with different oxygen contents using PECVD, highly efficient SHJ solar cells with an average efficiency of 25.37% were achieved. The trilayer passivation scheme demonstrated higher JSC, VOC, and slightly increased FF compared to solar cells with complete a-Si:H passivation layers.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Materials Science, Coatings & Films
Gamze Koekbudak, Ahmet E. Kececi, Hisham Nasser, Rasit Turan
Summary: The study investigated the passivation quality of ultra-thin Al2O3 on Cz p-type wafers for PERC solar cells. Results showed that ultra-thin Al2O3 thicknesses can provide superior passivation quality compared to commonly applied larger thicknesses, offering potential for cost reduction and efficiency improvements in industrial PERC solar cells.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2021)
Article
Engineering, Electrical & Electronic
Pengfei Wei, Rui Tong, Xiaofeng Liu, Yao Wei, Yongan Zhang, Xu Liu, Jian Dai, Haipeng Yin, Dongming Liu
Summary: This study investigates the influence of SiNx and SiOxNy as rear-side passivation films on the performance of PERC+ cells. SiNx film is found to have better passivation performance and resistance to aluminum paste erosion, while SiOxNy film exhibits better optical performance. By designing multi-layer SiNx/SiOxNy/SiNx stacks, the cells' efficiency and bifaciality are significantly improved.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2024)
Article
Energy & Fuels
A. Wratten, S. L. Pain, A. Yadav, E. Khorani, T. Niewelt, L. Black, G. Bartholazzi, D. Walker, N. E. Grant, J. D. Murphy
Summary: This study investigates the potential of ultra-thin HfO2 films grown by atomic layer deposition for passivating contacts to silicon. It specifically focuses on variations in film thickness and post-deposition annealing temperature. The results show that 2.2 nm thick films annealed at 475 degrees C exhibit the highest passivation quality. The effective work function of the films also decreases with decreasing thickness. A post-deposition annealing process reduces the effective work function further. The study also examines the contact resistivity in a passivating contact structure utilizing HfO2 and finds a temperature dependence on the annealing process. The lowest resistance is achieved below 375 degrees C.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Chemistry, Physical
Jianming Ding, Shuai Zou, Leilei Shen, Jonghyung Choi, Junhu Cui, Dichun Yuan, Chengkun Wu, Zheng Lu, Yulian Zeng, Ronglei Fan, Yadong Xu, Baochen Liao, Mingrong Shen, Xiaodong Su
Summary: This paper studied the influence of rear pyramid morphologies with different slope angles on the optical and electrical properties of bi-PERC solar cells. The results showed that a smoother rear surface was favorable for rear passivation but unfavorable for rear-side light trapping. Rear surface morphologies also influenced the front-side light trapping. The highest front-side average efficiency of 22.86% was achieved using a modified acidic polishing process.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Optics
Meili Cui, Jun Ma, Xuemei Wu
Summary: By developing high-quality multilayer SiNx:H films as anti-reflection and passivation coatings, the efficiency of industrial PERC solar cells can be improved. Simulation and experimental results showed that the four-layer SiNx:H film had the best performance, significantly increasing light absorption and short-circuit current density of the cells.
Article
Energy & Fuels
Mario Lehmann, Anatole Desthieux, Nathalie Valle, Audrey Morisset, Philippe Wyss, Santhana Eswara, Tom Wirtz, Andrea Ingenito, Pere Roca i Cabarrocas, Christophe Ballif, Franz-Josef Haug
Summary: This article investigates the effect of various processing steps during the fabrication of c-Si/SiOx/SiCx fired passivating contacts on the silicon bulk lifetime, as well as the kinetics of defect deactivation by hydrogenation. The results show a faster passivation of the surface and a slower passivation of shallow bulk defects. The kinetics of the hydrogenation process is limited by the available hydrogen supply at the c-Si/SiOx interface, rather than by diffusion within the bulk of the wafer.
IEEE JOURNAL OF PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Puzant Baliozian, Anna Muenzer, Elmar Lohmueller, Aathira Nair, Tobias Fellmeth, Nico Woehrle, Hannes Hoeffler, Alma Spribille, Ralf Preu
Summary: This study investigated the application of thermal laser separation (TLS) on silicon solar cells, revealing that the main losses in cell performance are attributed to recombination at the newly created unpassivated edges after complete TLS. The cleave process itself does not significantly impact the performance of the cells for both types investigated.
IEEE JOURNAL OF PHOTOVOLTAICS
(2021)
Article
Energy & Fuels
Benedikt Fischer, Wolfhard Beyer, Andreas Lambertz, Maurice Nuys, Weiyuan Duan, Kaining Ding, Uwe Rau
Summary: The application of thin underdense a-Si:H films for passivation of c-Si in SHJ solar cell technology has been investigated. The microstructure of underdense a-Si:H films was studied using Raman spectroscopy, effusion, and secondary ion mass spectrometry. The results showed that molecular hydrogen plays an important role in the passivation process. Solar cells using underdense a-Si:H as i1-layer achieved a maximum efficiency of 24.1%.
Article
Energy & Fuels
Tian Pu, Honglie Shen, Kuang Hong Neoh, Fei Ye, Quntao Tang
Summary: The study shows that adding a SiOx layer in P-type monocrystalline PERC cells can effectively reduce the influence of PID, with the AlOx + SiOx + SiNx stack performing well in breakdown voltage and power degradation.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Green & Sustainable Science & Technology
W. S. Yan, X. Y. Tan, L. Guan, H. P. Zhou, X. B. Yang, P. Xiang, Z. C. Zhong
Summary: The current study successfully achieved additional gains for 150 mm-thick cells through optical and electrical designs, leading to improvements in short circuit current density and open circuit voltage, thereby increasing absolute efficiency.
Article
Energy & Fuels
Stefan W. Glunz, Bernd Steinhauser, Jana-Isabelle Polzin, Christoph Luderer, Benjamin Gruebel, Tim Niewelt, Asmaa M. O. M. Okasha, Mathias Bories, Henning Nagel, Katrin Krieg, Frank Feldmann, Armin Richter, Martin Bivour, Martin Hermle
Summary: This paper provides an overview of the potential of passivating contacts based on poly-Si/SiOx structures known as TOPCon in improving the efficiency of crystalline silicon solar cells. It discusses the historical development of such contact structures and describes the current state-of-the-art in laboratory and industry. The paper also addresses four different research topics related to TOPCon technology, including re-parametrization of recombination in silicon, control of dopant diffusion, single-sided deposition of the poly-Si layer, and the fabrication of silicon-based tunnel junctions for perovskite-silicon tandem cells.
PROGRESS IN PHOTOVOLTAICS
(2023)
Article
Energy & Fuels
Christoph Messmer, Jonas Schoen, Sabrina Lohmueller, Johannes Greulich, Christoph Luderer, Jan Christoph Goldschmidt, Martin Bivour, Stefan W. Glunz, Martin Hermle
Summary: Low-cost and high-efficiency tandem solar cells show great potential for future industrial mass production. The passivated emitter and rear cell (PERC) technology, which currently dominates the market, can be used as the bottom cell concept for perovskite-silicon tandem devices. By reevaluating the current PERC technology and considering different front-side concepts, both full-area and locally contacted front-side designs are promising candidates for achieving tandem cell efficiencies of about 30%.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Patrick Schygulla, Ralph Muller, David Lackner, Oliver Hohn, Hubert Hauser, Benedikt Blasi, Felix Predan, Jan Benick, Martin Hermle, Stefan W. Glunz, Frank Dimroth
Summary: By optimizing the III-V top structure, the efficiency of a two-terminal wafer-bonded III-V//Si triple-junction solar cell was increased from 34.1% to 35.9%. The integration of a GaInAsP absorber in the middle cell led to an increase in open-circuit voltage, while better current matching of all subcells enhanced the short-circuit current. An upright grown structure achieved the highest cell efficiency of 35.9%, showcasing future improvement opportunities and limits.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Christian Reichel, Frank Feldmann, Armin Richter, Jan Benick, Martin Hermle, Stefan W. Glunz
Summary: Polysilicon contact structures were investigated with ultra-thin atomic layer deposited (ALD) oxide and nitride interlayers, showing that ALD SiOx single interlayers provided good passivation quality while ALD SiNx single interlayers also showed promising passivation quality. However, AlOx and AlNx interlayers only allowed for a moderate effect, and TiOx interlayers exhibited very poor passivation quality.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Christoph Messmer, Leonard Tutsch, Sebastian Pingel, Denis Erath, Jonas Schon, Andreas Fell, Jan Christoph Goldschmidt, Baljeet S. Goraya, Florian Clement, Andreas Lorenz, Sebastian Nold, Martin Bivour, Stefan W. Glunz, Martin Hermle
Summary: The study optimized the front electrode of perovskite-silicon tandem solar cells through optical and electrical modeling, resulting in significant findings such as adjusting the TCO thickness to reduce parasitic absorption and costs, and exploring different front metallization methods to reduce the number of wires for multi-wire interconnection concepts.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Salma Zouhair, Bin Luo, Dmitry Bogachuk, David Martineau, Lukas Wagner, Adil Chahboun, Stefan W. Glunz, Andreas Hinsch
Summary: This study found that high fill factors of up to 78.8% can be achieved through hole selective layer-free carbon-electrode perovskite solar cells. Non-radiative recombination contributes only 3% to the fill factor losses in optimized devices, while interface series resistance losses are identified as the main loss channel.
Article
Chemistry, Physical
Hemangi Patel, Christian Reichel, Armin Richter, Paul Masuch, Jan Benick, Stefan W. Glunz
Summary: Multilayer stacks were deposited on c-Si at different temperatures by PEALD technique to investigate the effect of dipoles or trapped charges at interfaces, showing that chemical passivation in multilayer stacks can be comparable to the Al2O3 single layer. Furthermore, the field-effect passivation quality of multilayer stacks can be tuned by manipulating O w in the stacks through voltage stress application.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Taisiia Berestok, Christian Diestel, Niklas Ortlieb, Stefan W. Glunz, Anna Fischer
Summary: This study proposes a photosupercapacitor that combines a solar cell with a supercapacitor, allowing for rechargeability under illumination. The integration of a silicon solar cell with mesoporous N-doped carbon nanospheres results in high energy storage efficiency and superior performance. The technology has the potential to be used in photorechargeable and decentralized power sources for deployed smart electronic devices.
ADVANCED MATERIALS TECHNOLOGIES
(2022)
Article
Energy & Fuels
Philipp Kunze, Johannes M. Greulich, Ammar Tummalieh, Wiebke Wirtz, Hannes Hoeffler, Nico Woehrle, Stefan Glunz, Stefan Rein, Matthias Demant
Summary: The current-voltage measurement is crucial in solar cell quality control. This study presents a contactless IV characterization method using an empirical model to derive full IV curves and parameters. Contactless measurements are based on photoluminescence, electroluminescence, and spectral reflectance data.
Article
Energy & Fuels
T. Hatt, P. S. C. Schulze, O. Er-Raji, A. Richter, R. Efinger, O. Schultz-Wittmann, M. Heydarian, L. Tutsch, J. C. Goldschmidt, M. Glatthaar, S. W. Glunz, J. Bartsch
Summary: Electroplated copper electrodes are manufactured for the first time for perovskite/silicon tandem solar cells, using thin ALD Al(2)O(3) masking layer and screen-printed Ag seed-layer. The electroplating process achieves a photoconversion efficiency up to 15%, and a light-induced Cu plating process without using a metal seed-layer on ITO is also demonstrated. The progress with the selective electroplating metallization for bifacial tandem solar cells is presented.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Energy & Fuels
Andreas Fell, Oliver Schultz-Wittmann, Christoph Messmer, Martin C. Schubert, Stefan W. Glunz
Summary: This article presents an efficient 3-D tandem modeling approach implemented in a solar cell simulation software, which helps in understanding and quantifying the influence of various effects on tandem cell development. The usefulness of this approach is demonstrated by investigating perimeter designs of small-area silicon-perovskite cells.
IEEE JOURNAL OF PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Christian O. Diestel, Rodrigo Delgado Andres, Stefan W. Glunz
Summary: In this study, a method is introduced to define a set of quality functions for photostorage devices, which can be used to evaluate devices unambiguously and provide useful metrics for all operating scenarios. This is achieved by identifying three fundamental modes of operation for a photostorage device and calculating a quality function for each mode using an equivalent circuit model. This approach avoids the use of variable physical parameters and allows for a rigid definition of device quality and reliable predictions of performance.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Energy & Fuels
Oliver Fischer, Andreas Fell, Christoph Messmer, Raphael Efinger, Florian Schindler, Stefan W. W. Glunz, Martin C. C. Schubert
Summary: To comprehensively characterize the electro-optical properties of perovskite silicon tandem devices, electro- and photoluminescence imaging are combined with illuminated lock-in thermography. This approach, along with numerical simulation models, allows for holistic investigations of device limitations. One remarkable feature observed in the investigated tandem device, showing a low photoluminescence but high electroluminescence signal at local spots, is suggested to originate from the perovskite/C-60 interface.
Proceedings Paper
Energy & Fuels
Felix Maischner, Stephan Maus, Johannes Greulich, Sabrina Lohmueller, Elmar Lohmueller, Pierre Saint-Cast, Daniel Ourinson, Karin Hergert, Stephan Riepe, Stefan Glunz, Stefan Rein
Summary: We have developed a fast firing oven (FFO) firing profile that can effectively mitigate the degradation issues of boron doped PERC cells under high temperature and light exposure. This technique not only shows promising results in the cells, but also maintains its mitigation effect during module production.
11TH INTERNATIONAL CONFERENCE ON CRYSTALLINE SILICON PHOTOVOLTAICS (SILICONPV 2021)
(2022)
Article
Materials Science, Multidisciplinary
Lukas Wagner, Patrick Schygulla, Jan Philipp Herterich, Mohamed Elshamy, Dmitry Bogachuk, Salma Zouhair, Simone Mastroianni, Uli Wuerfel, Yuhang Liu, Shaik M. Zakeeruddin, Michael Graetzel, Andreas Hinsch, Stefan W. Glunz
Summary: This paper presents a method for real-time assessment of solar cell performance using voltage-dependent photoluminescence microscopy. The proposed method allows for the determination of microscopically resolved J(V) curves and provides information on charge extraction and interfacial recombination, enabling the identification of non-ideal charge extraction regions and improvements in solar cells.
