Dissertations / Theses on the topic 'Crystalline silicon solar cells'
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1
Reuter, Michael [Verfasser]. "Thin Crystalline Silicon Solar Cells / Michael Reuter." München : Verlag Dr. Hut, 2011. http://d-nb.info/1012432041/34.
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Stüwe, David [Verfasser], and Jan G. [Akademischer Betreuer] Korvink. "Inkjet processes for crystalline silicon solar cells." Freiburg : Universität, 2015. http://d-nb.info/1122646984/34.
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Demircioglu, Olgu. "Optimization Of Metalization In Crystalline Silicon Solar Cells." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614584/index.pdf.
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ABSTRACT
OPTIMIZATION OF METALIZATION IN
CRYSTALLINE SILICON SOLAR CELLS
Demircioglu, Olgu
M. Sc. Department of Micro and Nanotechnology
Supervisor : Prof. Dr. Rasit Turan
Co-Supervisor : Assist. Prof. Dr. H. Emrah Ünalan August 2012, 103 pages Production steps of crystalline silicon solar cells include several physical and chemical processes like etching, doping, annealing, nitride coating, metallization and firing of the metal contacts. Among these processes, the metallization plays a crucial role in the energy conversion performance of the cell. The quality of the metal layers used on the back and the front surface of the cell and the quality of the electrical contact they form with the underlying substrate have a detrimental effect on the amount of the power generated by the cell. All aspects of the metal layer, such as electrical resistivity, contact resistance, thickness, height and width of the finger layers need to be optimized very carefully for a successful solar cell operation. In this thesis, metallization steps within the crystalline silicon solar cell production were studied in the laboratories of Center for Solar Energy Research and Application (GÜ
NAM). Screen Printing method, which is the most common metallization technique in the industry, was used for the metal layer formation. With the exception of the initial experiments, 6
4
Mahanama, G. D. K. "Low temperature processing of crystalline silicon solar cells." Thesis, London South Bank University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435235.
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Tahhan, Abdulla. "Energy performance enhancement of crystalline silicon solar cells." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/14503.
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The work in this thesis examines the effects of the application of oxide coatings on the performance of the single crystalline silicon photovoltaic solar cells. A variety of potential oxide materials for solar cells performance enhancement are investigated. These films are silicon oxide, titanium oxide and rare earth ion-doped gadolinium oxysulfide phosphor. This study compares the electrical characteristics, optical properties and surface chemical composition of mono-crystalline silicon cells before and after coating. The first study investigates the potential for using single and double layers of silicon oxide films produced by low-temperature Plasma Enhanced Chemical Vapour Deposition (PECVD) using tetramethylsilane as a silicon precursor and potassium permanganate oxidising agent for efficiency enhancement of solar cells at low manufacturing cost. Deposition of the films contributes to the increase of the conversion energy of the solar cells on one hand while the variety of colours obtained in this study can be of great importance for building-integrated photovoltaic application on the other hand. The obtained results demonstrated a relative enhancement of 3% in the conversion efficiency of the crystalline silicon solar cell. In the second study, the effects of using a single layer of titanium oxide and a stack of silicon oxide and titanium oxide on the performance of solar cell are demonstrated. Moreover, this study shows the use of different sputtering configurations and oxidation methods. The experimental results showed a relative enhancement of 1.6% for solar cells coated with a stack of silicon oxide/titanium oxide. In the third study, silicon cells were coated with a luminescent layer consisting of down-converting phosphor, gadolinium oxysulfide doped with erbium and terbium, and a polymeric binder of EVA using doctor-blade screen printing technique. A relative enhancement of 4.45% in the energy conversion efficiency of PV solar cell was achieved. Also, the effects of combining silicon oxide layers together with the luminescent composite are also presented in this study.
6
Ghosh, Kunal. "Modeling of amorphous silicon/crystalline silicon heterojunction by commercial simulator." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 48 p, 2009. http://proquest.umi.com/pqdweb?did=1654493871&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Es, Firat. "Fabrication And Characterization Of Single Crystalline Silicon Solar Cells." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612363/index.pdf.
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The electricity generation using photovoltaic (PV) solar cells is the most viable and promising alternative to the fossil-fuel based technologies which are threatening world&rsquos climate. PV cells directly convert solar energy into electrical power through an absorption process that takes place in a solid state device which is commonly fabricated using semiconductors. These devices can be employed for many years with almost no degradation and maintenance. PV technologies have been diversified in different directions in recent years. Many technologies with different advantages have been developed. However, with more than %85 percent market share, Si wafer based solar cells have been the most widely used solar cell type. This is partly due to the fact that Si technology is well known from the microelectronic industry. This thesis is concerned with the production of single crystalline silicon solar cells and optimization of process parameters through the characterization of each processing step. Process steps of solar cell fabrications, namely, the light trapping by texturing, cleaning, solid state diffusion, lithography, annealing, anti reflective coating, edge isolation have all been studied with a systematic approach. Each sample set has been characterized by measuring I-V characteristics, quantum efficiencies and reflectance characteristics. The best efficiency that we reached during this study is 10.37% under AM1.5G illumination. This is below the efficiency values of the commercially available solar cells. The most apparent reason for the low efficiency value is the series resistance caused by the thin metal contacts. It is observed that the efficiency upon the reduction of series resistance effect is reduced. We have shown that the texturing and anti-reflective coating have a critically important effect for light management for better efficiency values. Finally we have investigated the fabrication of metal nanoparticles on the Si wafer for possible utilization of plasmonic oscillation in them for light trapping. The self assembly formation of gold nanoparticles on silicon surface has been successfully demonstrated. The optical properties of the nanoparticles have been studied
however, further and more detailed analysis is required.
8
Renshaw, John. "Numerical modeling and fabrication of high efficiency crystalline silicon solar cells." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/49068.
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Crystalline silicon solar cells translate energy from the sun into electrical energy via the photoelectric effect. This technology has the potential to simultaneously reduce carbon emissions and our dependence on fossil fuels. The cost of photovoltaic energy, however, is still higher than the cost of electricity off of the grid which hampers this technologies adoption. Raising solar cell efficiency without significantly raising the cost is crucial to lowering the cost of photovoltaic produced energy. One technology which holds promise to increase solar cell efficiency is a selective emitter solar cell. In this work the benefit of selective emitter solar cells is quantified through numerical modeling. Further, the use of ultraviolet laser to create a laser doped selective emitter solar cell is explored. Through optimization of the laser doping process to minimize laser induced defects it is shown that this process can increase solar cell efficiency to over 19.1%. Additionally, 2D and 3D numerical modeling are performed to determine the limitations screen printed interdigitated back contact solar cells and the practical efficiency limit for crystalline Si solar cells.
9
Peters, Stefan. "Rapid thermal processing of crystalline silicon materials and solar cells /." Allensbach : UFO Atelier für Gestaltung und Verlag, 2004. http://www.loc.gov/catdir/toc/fy0805/2007493330.html.
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Kieliba, Thomas. "Zone-melting recrystallization for crystalline silicon thin-film solar cells." Berlin dissertation.de, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2898611&prov=M&dok_var=1&dok_ext=htm.
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Ernst, Marco [Verfasser]. "Macroporous silicon for crystalline thin-film solar cells / Marco Ernst." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2013. http://d-nb.info/1047351552/34.
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Hinken, David [Verfasser]. "Luminescence-based characterization of crystalline silicon solar cells / David Hinken." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2012. http://d-nb.info/1024816141/34.
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13
Branham, Matthew S. "Ultrathin crystalline silicon solar cells incorporating advanced light-trapping structures." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97833.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 105-110).
Solar photovoltaics, which convert the energy potential of photons from the sun directly into electrical power, hold immense promise as a cornerstone of a clean energy future. Yet their cost remains greater than that of conventional energy sources in most markets and a barrier to large-scale adoption. Crystalline silicon modules, with a 90% share of the worldwide photovoltaic market, have witnessed a precipitous drop in price over the last decade. But going forward, further evolutionary cost reduction will be difficult given the significant cost of the silicon wafer alone - roughly 35% of the module. Dramatically reducing the thickness of silicon used to make a solar cell from the current 350 [mu]m could rewrite the economics of photovoltaics. For thin-film crystalline silicon solar cells to deliver the anticipated cost benefits of reduced material requirements, it is essential that they also yield power conversion efficiencies comparable to commercial solar cells. A significant hurdle to realizing elevated efficiency in crystalline silicon films thinner than 20 [mu]m is the loss of current resulting from reduced photon absorption. A range of light management structures have been proposed in the literature to address this issue and many have been demonstrated to provide high absorption across the spectral range relevant to crystalline silicon, but their promise has yet to be realized in an active photovoltaic device. The focus of this thesis is the development of an experimental platform and fabrication process to evaluate the effectiveness of theoretically-designed light-trapping structures in functional photovoltaic devices. The experimental effort yielded 10-pm-thick crystalline silicon solar cells with a peak short-circuit current of 34.5 mA cm-² and power conversion efficiency of 15.7%. The record performance for a crystalline silicon photovoltaic of such thinness is enabled by an advanced light-trapping design incorporating a 2D photonic crystal and a rear dielectric/reflector stack. A parallel line of questioning addressed in this thesis is whether periodic wavelength-scale optical structures are superior to periodic or random structures with geometric-optics-scale features. Through the synthesis of experimental and theoretical evidence, the case is constructed that wavelength-scale light-trapping structures are in fact comparable to conventional random pyramid surface structures for broad-spectrum absorption in silicon solar cells as thin as 5 [mu]m. These results have important implications for the design of cost-effective and manufacturable light-trapping structures for ultrathin crystalline silicon solar cells.
by Matthew S. Branham.
Ph. D.
14
Powell, Douglas M. (Douglas Michael). "Simulation of iron impurity gettering in crystalline silicon solar cells." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/74988.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 52-56).
This work discusses the Impurity-to-Efficiency (12E) simulation tool and applet. The 12E simulator models the physics of iron impurity gettering in silicon solar cells during high temperature processing. The tool also includes a device simulator to calculate cell performance after processing. By linking input materials, processing, and cell performance, 12E enables accelerated solar cell optimization. Herein, background information on the economic drivers of solar cell installations and manufacturing are used to introduce the importance of iron impurity engineering. The fundamental physics of gettering and the development of the numerical methods employed by the tool are presented. The development, deployment, and use of the web applet are also discussed.
by Douglas M. Powell.
S.M.
15
Helland, Susanne. "Electrical Characterization of Amorphous Silicon Nitride Passivation Layers for Crystalline Silicon Solar Cells." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16310.
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High quality surface passivation is important for the reduction of recombination losses in solar cells. In this work, the passivation properties of amorphous hydrogenated silicon nitride for crystalline silicon solar cells were investigated, using electrical characterization, lifetime measurements and spectroscopic ellipsometry. Thin films of varying composition were deposited on p-type monocrystalline silicon wafers by plasma enhanced chemical vapor deposition (PECVD). Highest quality surface passivation was obtained for silicon-rich thin films, where a surface recombination velocity of 30 cm/s was obtained after a heat treatment corresponding to the industrial contact firing process. Electrical characterization of the interface between silicon nitride and silicon was performed by capacitance and conductance measurements. Several challenging aspects related to the interpretation of these measurements were investigated in detail, including charging and discharging, leakage currents, and frequency dependent capacitance.
16
Hörteis, Matthias [Verfasser]. "Fine-line printed contacts on crystalline silicon solar cells / Matthias Hörteis." Konstanz : Bibliothek der Universität Konstanz, 2009. http://d-nb.info/1017360413/34.
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Eisenlohr, Johannes [Verfasser]. "Light Trapping in High-Efficiency Crystalline Silicon Solar Cells / Johannes Eisenlohr." Konstanz : Bibliothek der Universität Konstanz, 2017. http://d-nb.info/1173087656/34.
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Halbich, Marc-Uwe [Verfasser]. "Organic Selective Contacts for Crystalline Silicon Solar Cells / Marc-Uwe Halbich." Hannover : Gottfried Wilhelm Leibniz Universität, 2021. http://d-nb.info/1229614931/34.
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19
Mulati, David M. "Electrical Characterizantion of Multi-crystalline Silicon Solar Cells for High Efficiency." Kyoto University, 1999. http://hdl.handle.net/2433/181299.
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20
Kaminski, Piotr M. "Remote plasma sputtering for silicon solar cells." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13058.
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The global energy market is continuously changing due to changes in demand and fuel availability. Amongst the technologies considered as capable of fulfilling these future energy requirements, Photovoltaics (PV) are one of the most promising. Currently the majority of the PV market is fulfilled by crystalline Silicon (c-Si) solar cell technology, the so called 1st generation PV. Although c-Si technology is well established there is still a lot to be done to fully exploit its potential. The cost of the devices, and their efficiencies, must be improved to allow PV to become the energy source of the future. The surface of the c-Si device is one of the most important parts of the solar cell as the surface defines the electrical and the optical properties of the device. The surface is responsible for light reflection and charge carrier recombination. The standard surface finish is a thin film layer of silicon nitride deposited by Plasma Enhanced Chemical Vapour Deposition (PECVD). In this thesis an alternative technique of coating preparation is presented. The HiTUS sputtering tool, utilising a remote plasma source, was used to deposit the surface coating. The remote plasma source is unique for solar cells application. Sputtering is a versatile process allowing growth of different films by simply changing the target and/or the deposition atmosphere. Apart from silicon nitride, alternative materials to it were also investigated including: aluminium nitride (this was the first use of the material in solar cells) silicon carbide, and silicon carbonitride. All the materials were successfully used to prepare solar cells apart from the silicon carbide, which was not used due to too high a refractive index. Screen printed solar cells with a silicon nitride coating deposited in HiTUS were prepared with an efficiency of 15.14%. The coating was deposited without the use of silane, a hazardous precursor used in the PECVD process, and without substrate heating. The elimination of both offers potential processing advantages. By applying substrate heating it was found possible to improve the surface passivation and thus improve the spectral response of the solar cell for short wavelengths. These results show that HiTUS can deposit good quality ARC for silicon solar cells. It offers optical improvement of the ARC s properties, compared to an industrial standard, by using the DL-ARC high/low refractive index coating. This coating, unlike the silicon nitride silica stack, is applicable to encapsulated cells. The surface passivation levels obtained allowed a good blue current response.
21
Hsu, Wei-Chun. "Harvesting photon energy : ultra-thin crystalline silicon solar cell & near-field thermoradiative cells." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104252.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 134-148).
Photons from the sun and terrestrial sources have great potential to satisfy the energy demand of humans. This thesis studies two types of energy conversion technologies, photovoltaic solar cells based on crystalline silicon thin films and thermal-radiative cells using terrestrial heat sources, focusing on managing photons but also concurrently considering electron transport and entropy generation. Photovoltaic technology has been widely adopted to convert solar energy into electricity. Crystalline silicon material occupies ~90% of the photovoltaic market. However, the silicon material in a photovoltaic module with ~180-pm-thick silicon material contributes more than 30% of the overall cost, giving rise to an obstacle to compete with fossil fuel energy. One promising solution to break this barrier is the technology of thin-film crystalline silicon solar cells if the weak absorption of silicon can be overcome. To maintain its high energy conversion efficiency, nanostructure is designed considering both light trapping and electron collection. This design guided the fabrication of 10-pm-thick crystalline silicon photovoltaic cells with efficiencies as high as 15.7%. To reach efficiency >20% in industry, multiple strategies have been investigated to further improve the performance including the least-common-multiple rule for the double gratings structure, external optical cavity, high quality silicon in bulk material and interfaces, and optimal contact spacing and doping. For the energy conversion of terrestrial heat source, a direct bandgap solar cell can work in the reverse bias mode to convert energy into electricity companied by emission of photons as entropy carriers. Photon spectral entropy and fluxes are used to develop strategies for improving the heat to electricity conversion efficiency. Near-field radiative transfer, especially using phonon polariton material to couple out emitted photons from electron-hole recombination, is proposed to enhance energy conversion efficiency as well as the power density. We predict that the InSb thermoradiative cell can achieve the efficiency and power density up to 20.4 % and 327 Wm-2, respectively, between a hot source at 500K and a cold sink at 300K, if the sub-bandgap and non-radiative losses could be avoided.
by Wei-Chun Hsu.
Ph. D.
22
Kittidachachan, Pattareeya. "Reducing the cost of crystalline silicon solar cells by using fluorescent collectors." Thesis, University of Southampton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507624.
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Ximello, Quiebras Jose Nestor [Verfasser]. "Wet chemical textures for crystalline silicon solar cells / Jose Nestor Ximello Quiebras." Konstanz : Bibliothek der Universität Konstanz, 2013. http://d-nb.info/1045840572/34.
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Wang, Licai. "Crystalline silicon thin film growth by ECR plasma CVD for solar cells." Thesis, London South Bank University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297927.
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25
Kwapil, Wolfram [Verfasser]. "Alternative materials for crystalline silicon solar cells : risks and implications / Wolfram Kwapil." Konstanz : Bibliothek der Universität Konstanz, 2010. http://d-nb.info/1017235988/34.
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26
Schubert, Gunnar. "Thick Film Metallisation of Crystalline Silicon Solar Cells Mechanisms, Models and Applications /." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:352-opus-25592.
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27
Hofmann, Marc. "Rear surface conditioning and passivation for locally contacted crystalline silicon solar cells." München Verl. Dr. Hut, 2008. http://d-nb.info/992163250/04.
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28
Forster, Maxime. "Compensation engineering for silicon solar cells." Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00876318.
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This thesis focuses on the effects of dopant compensation on the electrical properties of crystalline silicon relevant to the operation of solar cells. We show that the control of the net dopant density, which is essential to the fabrication of high-efficiency solar cells, is very challenging in ingots crystallized with silicon feedstock containing both boron and phosphorus such as upgraded metallurgical-grade silicon. This is because of the strong segregation of phosphorus which induces large net dopant density variations along directionally solidified silicon crystals. To overcome this issue, we propose to use gallium co-doping during crystallization, and demonstrate its potential to control the net dopant density along p-type and n-type silicon ingots grown with silicon containing boron and phosphorus. The characteristics of the resulting highly-compensated material are identified to be: a strong impact of incomplete ionization of dopants on the majority carrier density, an important reduction of the mobility compared to theoretical models and a recombination lifetime which is determined by the net dopant density and dominated after long-term illumination by the boron-oxygen recombination centre. To allow accurate modelling of upgraded-metallurgical silicon solar cells, we propose a parameterization of these fundamental properties of compensated silicon. We study the light-induced lifetime degradation in p-type and n-type Si with a wide range of dopant concentrations and compensation levels and show that the boron-oxygen defect is a grown-in complex involving substitutional boron and is rendered electrically active upon injection of carriers through a charge-driven reconfiguration of the defect. Finally, we apply gallium co-doping to the crystallization of upgraded-metallurgical silicon and demonstrate that it allows to significantly increase the tolerance to phosphorus without compromising neither the ingot yield nor the solar cells performance before light-induced degradation.
29
Eygi, Zeynep Deniz. "Production Of Amorphous Silicon/ P-type Crystalline Silicon Heterojunction Solar Cells By Sputtering And Pecvd Methods." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613999/index.pdf.
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Silicon heterojunction solar cells, a-Si:H/c-Si, are promising technology for future photovoltaic systems. An a-Si:H/c-Si heterojunction solar cell combines the advantages of single crystalline silicon photovoltaic with thin-film technologies. This thesis reports a detailed survey of heterojunction silicon solar cells with p-type wafer fabricated by magnetron sputtering and Plasma Enhanced Chemical Vapor Deposition (PECVD) techniques at low processing temperature. In the first part of this study, magnetron sputtering method was employed to fabricate a-Si:H thin films and then a-Si:H/c-Si solar cells. Amorphous silicon (a-Si:H) films were grown on glass in order to perform electrical and optical characterizations. The J-V characteristics of the silicon heterojunction solar cells were analyzed as a function of a-Si:H properties. It was shown that a-Si thin films with well-behaved chemical and electronic properties could be fabricated by the magnetron sputtering. Hydrogenation of the grown film could be achieved by H2 introduction into the chamber during the sputtering. In spite of the good film properties, fabricated solar cells had poor photovoltaic parameters with a low rectification characteristic. This low device performance was caused by high resistivity and low doping concentration in the sputtered film. The second part of the thesis is dedicated to heterojunction solar cells fabricated by PECVD. In this part a systematic study of various PECVD processing parameters were carried out to optimize the a-Si:H(n) emitter properties for the a-Si:H(n)/c-Si(p) solar cell applications. In the next stage, a thin optimized a-Si:H(i) buffer layer was included on the emitter side and on the rear side of the c-Si(p) to improve the surface passivation. Insertion of an a-Si:H(i) buffer layer yielded higher high open circuit voltage (Voc) with lower fill factor. It was shown that high Voc is due to the efficient surface passivation by the front/rear intrinsic layer which was also confirmed by the measurement of high effective lifetime for photo-generated carriers. Low fill factor on the other hand is caused by increasing resistivity of the solar cells by inserting low conductivity a-Si:H(i) layers.
30
Fernández, Robledo Susana [Verfasser], and Eicke [Akademischer Betreuer] Weber. "Laser-induced forward transfer based boron selective emitters for crystalline silicon solar cells." Freiburg : Universität, 2021. http://d-nb.info/122665715X/34.
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31
Schmich, Evelyn Karin. "High-temperature CVD processes for crystalline silicon thin-film and wafer solar cells." München Verl. Dr. Hut, 2008. http://d-nb.info/992162874/04.
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32
Hudelson, George David Stephen III. "High temperature investigations of crystalline silicon solar cell materials." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/50568.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.Includes bibliographical references (p. 74-78).
Crystalline silicon solar cells are a promising candidate to provide a sustainable, clean energy source for the future. In order to bring about widespread adoption of solar cells, much work is needed to reduce their cost. Herein, I discuss the development of a new experimental technique to investigate solar cell materials under simulated processing conditions. I present the first applications and results using this technique, including observations of novel impurity interactions at elevated temperatures, and discuss their importance to the solar cell manufacturing process. One of the key drivers for reducing solar cell cost is developing a fundamental understanding of the behavior of defect and impurities in solar cell materials. Since solar cell processing occurs at high temperatures, experiments are needed that allow characterization of solar cell materials at high temperatures representative of manufacturing conditions, at the length-scales of the defects that are present. To achieve this, I have developed a novel in situ high temperature sample stage for measuring samples via synchrotron-based X-ray microprobe. This technique allows for mapping and chemical state determination of metal impurity clusters on the order of 100 nm to 100 [mu]m, over sample areas of several square millimeters, at temperatures in excess of 1200°C and under controlled ambient atmosphere. The application of this technique has yielded novel insights concerning the behavior of metal impurities at high temperature.
(cont.) For the first time, the phenomenon of retrograde melting (i.e. melting on cooling) has been observed in a semiconductor material. Internal gettering of dissolved metal to liquid metal-silicon droplets within the silicon matrix is observed. Understanding of this phenomenon provides the potential to improve solar cell devices by reducing the more-detrimental dissolved metal content within the material by concentrating it into precipitates. Finally, I provide results and a model that explains the formation and resulting morphology of mixed-metal silicide precipitates in multicrystalline silicon.
by George David Stephen Hudelson, III.
S.M.
33
Forster, Maxime. "Compensation engineering for silicon solar cells." Phd thesis, INSA de Lyon, 2012. http://hdl.handle.net/1885/156020.
Full textAbstract:
This thesis focuses on the effects of dopant compensation on the electrical properties of crystalline silicon relevant to the operation of solar cells. We show that the control of the net dopant density, which is essential to the fabrication of high-efficiency solar cells, is very challenging in ingots crystallized with silicon feedstock containing both boron and phosphorus such as upgraded metallurgical-grade silicon. This is because of the strong segregation of phosphorus which induces large net dopant density variations along directionally solidified silicon crystals. To overcome this issue, we propose to use gallium co-doping during crystallization, and demonstrate its potential to control the net dopant density along p-type and n-type silicon ingots grown with silicon containing boron and phosphorus. The characteristics of the resulting highly-compensated material are identified to be: a strong impact of incomplete ionization of dopants on the majority carrier density, an important reduction of the mobility compared to theoretical models and a recombination lifetime which is determined by the net dopant density and dominated after long-term illumination by the boron-oxygen recombination centre. To allow accurate modelling of upgraded-metallurgical silicon solar cells, we propose a parameterization of these fundamental properties of compensated silicon. We study the light-induced lifetime degradation in p-type and n-type Si with a wide range of dopant concentrations and compensation levels and show that the boron-oxygen defect is a grown-in complex involving substitutional boron and is rendered electrically active upon injection of carriers through a charge-driven reconfiguration of the defect. Finally, we apply gallium co-doping to the crystallization of upgraded-metallurgical silicon and demonstrate that it allows to significantly increase the tolerance to phosphorus without compromising neither the ingot yield nor the solar cells performance before light-induced degradation.
34
Kerr, Mark John, and Mark Kerr@originenergy com au. "Surface, Emitter and Bulk Recombination in Silicon and Development of Silicon Nitride Passivated Solar Cells." The Australian National University. Faculty of Engineering and Information Technology, 2002. http://thesis.anu.edu.au./public/adt-ANU20040527.152717.
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[Some symbols cannot be rendered in the following metadata please see the PDF file for an accurate version of the Abstract]
¶
Recombination within the bulk and at the surfaces of crystalline silicon has been
investigated in this thesis. Special attention has been paid to the surface passivation achievable
with plasma enhanced chemical vapour deposited (PECVD) silicon nitride (SiN) films due to
their potential for widespread use in silicon solar cells. The passivation obtained with thermally
grown silicon oxide (SiO2) layers has also been extensively investigated for comparison.
¶
Injection-level dependent lifetime measurements have been used throughout this thesis to
quantify the different recombination rates in silicon. New techniques for interpreting the
effective lifetime in terms of device characteristics have been introduced, based on the physical
concept of a net photogeneration rate. The converse relationships for determining the effective
lifetime from measurements of the open-circuit voltage (Voc) under arbitrary illumination have
also been introduced, thus establishing the equivalency of the photoconductance and voltage
techniques, both quasi-static and transient, by allowing similar possibilities for all of them.
¶
The rate of intrinsic recombination in silicon is of fundamental importance. It has been
investigated as a function of injection level for both n-type and p-type silicon, for dopant
densities up to ~5x1016cm-3. Record high effective lifetimes, up to 32ms for high resistivity
silicon, have been measured. Importantly, the wafers where commercially sourced and had
undergone significant high temperature processing. A new, general parameterisation has been
proposed for the rate of band-to-band Auger recombination in crystalline silicon, which
accurately fits the experimental lifetime data for arbitrary injection level and arbitrary dopant
density. The limiting efficiency of crystalline silicon solar cells has been re-evaluated using this
new parameterisation, with the effects of photon recycling included.
¶
Surface recombination processes in silicon solar cells are becoming progressively more
important as industry drives towards thinner substrates and higher cell efficiencies. The surface
recombination properties of well-passivating SiN films on p-type and n-type silicon have been
comprehensively studied, with Seff values as low as 1cm/s being unambiguously determined.
The well-passivating SiN films optimised in this thesis are unique in that they are stoichiometric
in composition, rather than being silicon rich, a property which is attributed to the use of dilute
silane as a process gas. A simple physical model, based on recombination at the Si/SiN interface
being determined by a high fixed charge density within the SiN film (even under illumination),
has been proposed to explain the injection-level dependent Seff for a variety of differently doped
wafers. The passivation obtained with the optimised SiN films has been compared to that
obtained with high temperature thermal oxides (FGA and alnealed) and the limits imposed by
surface recombination on the efficiency of SiN passivated solar cells investigated. It is shown
that the optimised SiN films show little absorption of UV photons from the solar spectrum and
can be easily patterned by photolithography and wet chemical etching.
¶
The recombination properties of n+ and p+ emitters passivated with optimised SiN films
and thermal SiO2 have been extensively studied over a large range of emitter sheet resistances.
Both planar and random pyramid textured surfaces were studied for n+ emitters, where the
optimised SiN films were again found to be stoichiometric in composition. The optimised SiN
films provided good passivation of the heavily doped n+-Si/SiN interface, with the surface
recombination velocity increasing from 1400cm/s to 25000cm/s as the surface concentration of
electrically active phosphorus atoms increased from 7.5x1018cm-3 to 1.8x1020cm-3. The
optimised SiN films also provided reasonable passivation of industrial n+ emitters formed in a
belt-line furnace. It was found that the surface recombination properties of SiN passivated p+
emitters was poor and was worst for sheet resistances of ~150./ . The hypothesis that
recombination at the Si/SiN interface is determined by a high fixed charge density within the
SiN films was extended to explain this dependence on sheet resistance. The efficiency potential
of SiN passivated n+p cells has been investigated, with a sheet resistance of 80-100./ and a
base resistivity of 1-2.cm found to be optimal. Open-circuit voltages of 670-680mV and
efficiencies up to ~20% and ~23% appear possible for SiN passivated planar and textured cells
respectively. The recombination properties measured for emitters passivated with SiO2, both n+
and p+, were consistent with other studies and found to be superior to those obtained with SiN
passivation.
¶
Stoichiometric SiN films were used to passivate the front and rear surfaces of various
solar cell structures. Simplified PERC cells fabricated on 0.3.cm p-type silicon, with either a
planar or random pyramid textured front surface, produced high Vocs of 665-670mV and
conversion efficiencies up to 19.7%, which are amongst the highest obtained for SiN passivated
solar cells. Bifacial solar cells fabricated on planar, high resistivity n-type substrates (20.cm)
demonstrated Vocs up to 675mV, the highest ever reported for an all-SiN passivated cell, and
excellent bifaciality factors. Planar PERC cells fabricated on gettered 0.2.cm multicrystalline
silicon have also demonstrated very high Vocs of 655-659mV and conversion efficiencies up to
17.3% using a single layer anti-reflection coating. Short-wavelength internal quantum efficiency
measurements confirmed the excellent passivation achieved with the optimised stoichiometric
SiN films on n+ emitters, while long-wavelength measurements show that there is a loss of
short-circuit current at the rear surface of SiN passivated p-type cells. The latter loss is
attributed to parasitic shunting, which arises from an inversion layer at the rear surface due to
the high fixed charge (positive) density in the SiN layers. It has been demonstrated that that a
simple way to reduce the impact of the parasitic shunt is to etch away some of the silicon from
the rear contact dots. An alternative is to have locally diffused p+ regions under the rear
contacts, and a novel method to form a rear structure consisting of a local Al-BSF with SiN
passivation elsewhere, without using photolithography, has been demonstrated.
35
Bartsch, Jonas [Verfasser]. "Advanced Front Side Metallization for Crystalline Silicon Solar Cells with Electrochemical Techniques / Jonas Bartsch." München : Verlag Dr. Hut, 2012. http://d-nb.info/1020298839/34.
Full text
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Kieliba, Thomas [Verfasser]. "Zone-melting recrystallization for crystalline silicon thin-film solar cells / vorgelegt von Thomas Kieliba." Berlin : dissertation.de, 2006. http://d-nb.info/994900880/34.
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Rühle, Karola [Verfasser], and Leonhard M. [Akademischer Betreuer] Reindl. "Investigation and characterization of crystalline silicon solar cells for indoor and low light applications." Freiburg : Universität, 2015. http://d-nb.info/1122646828/34.
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Cabrera, Campos Enrique [Verfasser]. "Screen Printed Silver Contacting Interface in Industrial Crystalline Silicon Solar Cells / Enrique Cabrera Campos." Konstanz : Bibliothek der Universität Konstanz, 2013. http://d-nb.info/1045840548/34.
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Köhler, Malte [Verfasser], Uwe [Akademischer Betreuer] Rau, and Robby [Akademischer Betreuer] Peibst. "Transparent passivating contact for crystalline silicon solar cells / Malte Köhler ; Uwe Rau, Robby Peibst." Aachen : Universitätsbibliothek der RWTH Aachen, 2020. http://d-nb.info/1240904681/34.
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Catchpole, Kylie. "Thin crystalline silicon solar cells." Phd thesis, 2001. http://hdl.handle.net/1885/147956.
Full text
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Yung, Chi-Hang, and 楊麒翰. "Study of Silicon Nanorods/Crystalline Silicon Heterojunction Solar Cells." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/a3a2wc.
Full textAbstract:
碩士國立虎尾科技大學
材料科學與綠色能源工程研究所
97
In this thesis, the vapor-liquid-solid technique was adopted to develop the silicon nanorods (SNRs) as the emitter and the absorber layer of solar cells. By modulated the various ambient flow, growth temperature and time, the SNRs can be achieved for the silicon heterojunction solar cell devices applications. The enhanced properties of solar cells with SiNx as anti-reflection coating (ARC), including conversion efficiency, open-circuit voltage, short-circuit current, and fill factor, were demonstrated. According to the optimization of these process conditions, the efficiency of the Al/N+-SNRs/I-type SNRs/I-type poly-Si/ P-type Si structured thin-film solar cells with SiH4:N2=25:100 (sccm) and deposition time of 60 min, can be achieved around 1.9%. To increase the area of the p-type Si/n-type Si junction, the SNWs were obtained using the mixed AgNO3/HF solution wet etching method. By modulated the etching depth, diffusion time and temperature, the conversion efficiency (CE) of the Al/N+-SNWs/I-type SNWs/I-type poly-Si/P-type Si structured solar cell can be achieved around 4.41%. The process conditions include etching depth of 660nm, diffusion time of 3hr, and diffusion temperature of 950oC. Furthermore, the CE of the Al/N+-SNWs/I-type SNWs/I-type poly-Si/P-type Si structured solar cell with SiNx as ARC can be increased to 5.5%.
42
Bullock, James. "Advanced Contacts For Crystalline Silicon Solar Cells." Phd thesis, 2016. http://hdl.handle.net/1885/110957.
Full textAbstract:
Mainstream dopant-diffused crystalline silicon (c-Si) solar cells have reached a point in their development where losses at the directly-metalized, heavily-doped regions have a significant, and often limiting effect on device performance. The conventional wisdom on addressing this issue is to drastically reduce the percentage of the contacted surface area–to less than 1% in some cases–significantly increasing the complexity of fabrication. An alternative approach is to focus on addressing the losses at the metal / cSi interface by implementing novel ‘carrier-selective’ contacting structures. This approach to solar cell contacting has the potential to increase the output power whilst significantly simplifying cell architectures and fabrication procedures. This thesis is centered on the conceptual and experimental development of a number of advanced contacting structures for c-Si solar cells, collectively referred to here as ‘heterocontacts’. The ‘carrier-selectivity’ of the contact, that is, how well it collects just one of the two carriers (whilst preserving the other), is used as a universal concept for comparing different contacting strategies, including mainstream contacts based on direct metallization of heavily doped c-Si. To provide a foundation on this topic the initial section of the thesis discusses the concept and theory of carrier-selectivity. This is complemented with an in depth literature review of current state-of-the-art contacting practices for c-Si solar cells. This provides a reference frame with which to compare the three experimental chapters that follow. In the first experimental chapter it is shown that a suitable initial stepping stone towards advancing solar c-Si cell contacts is to combine the benefits of conventional dopant-diffused regions with those of heterocontacts. A number of such hybrid systems are demonstrated and optimized at the contact level through multiple dedicated studies focused on using thin silicon oxide (SiOx), aluminum oxide (AlOx) or hydrogenated amorphous silicon (a-Si:H) passivating interlayers. These interlayers are shown to reduce carrier recombination at the contact surface by up to two orders of magnitude. In a later study we develop and demonstrate a novel a-Si:H enhanced Al / SiOx / c-Si(n+) heterocontact concept. This structure is also explored at the solar cell level, yielding an efficiency of 21% in the initial stages of development – equivalent to that of an analogous cell made with the conventional directly metallized partial contact technique. In the succeeding chapter, the logical next stage in the development of such a concept is explored, that is, to completely remove the heavily doped surface regions, instead using the heterocontacts exclusively to separate electrons and holes. It is demonstrated that this can be achieved using materials with extreme work functions. For the collection of holes, sub-stoichiometric molybdenum oxide MoOx is utilized, favored for its transparency and large work function. Over multiple studies, it is demonstrated that MoOx heterocontact systems, both with and without passivating interlayers can be used to effectively collect holes on both n and p-type c-Si absorbers. This enables its application to a number of novel solar cells architectures, most prominently a novel MoOx partial rear contact cell attaining conversion efficiencies over 20% in the initial proof-ofconcept stage. In the final experimental chapter, a complementary electron heterocontact system is developed, based on a low work function LiFx / Al electrode. This is shown to provide ix excellent electron collection characteristics, both with and without a-Si:H passivating interlayers. The exceptional contact characteristics enabled by this heterocontact allow the demonstration of a first-of-its-kind n-type partial rear contact cell already with an efficiency above 20% in its first demonstration. To conclude the thesis and demonstrate its premise, a novel c-Si cell is developed without the use of dopants. This cell, referred to as the dopant free asymmetric heterocontact (DASH) cell, combines the previously mentioned MoOx based hole contacts and LiFx based electron heterocontacts, both with passivating a-Si:H interlayers. A conversion efficiency of 19.4% is attained for this proof-of-concept device— an improvement by more than 5 percent absolute from the previous DASH cell record and more importantly the first demonstration of such a concept to be competitive with conventional cell designs.
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Chiu, Ming-Hui, and 邱銘暉. "Deeply Etched Single Crystalline Silicon Solar Cells." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/84687497281207943571.
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Chang, Pai-Yu, and 張百裕. "Research on Crystalline-Silicon Solar Cells with Silicon-Germanium Films." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/hq7kfj.
Full textAbstract:
博士國立雲林科技大學
工程科技研究所博士班
101
The main purpose of this work is to investigate the process development of poly-SiGe films by aluminum-induced crystallization (AIC) and to form the hetero-structured single-crystalline Si/poly-SiGe solar cells. The device simulation of the hetero-structured sc-Si/poly-SiGe solar cells was done with the T-CAD tool. After the process development of the hetero-structured sc-Si/poly-SiGe solar cells, the photovoltaic (PV) characterization of the hetero-structured sc-Si/poly-SiGe solar cells was carried out under AM1.5G solar illumination. Experimentally, the Al and Ge films were evaporated onto the sc-Si substrate to form an a-Ge/Al/sc-Si structure that was annealed at 450°C–550°C for 0–3 h. The x-ray diffraction patterns confirmed that the initial transition from an amorphous to a polycrystalline structure occurs after 20 min of aluminum-induced crystallization (AIC) annealing process at 450°C. The Micro-Raman spectral analysis showed that the AIC process yields a better poly-SiGe film when the film is annealed at 450°C for 40 min. The poly-SiGe films on sc-Si wafer has higher absorption in the long wavelength range than sc-Si wafer; especially, the poly-SiGe film with smaller energy gap has broader absorption range to increase the efficiency of sc-Si based solar cells. In this work, poly-SiGe film has been used to increase the long-wavelength absorption characteristic of the Si solar cells. The poly-SiGe film can achieve a Δη = 14.661% that η(sc-Si/poly-SiGe) = 14.171%. The sc-Si/poly-SiGe structure can improve the PV performance of the Si-based solar cells.
45
Chen, Kun-Cheng, and 陳坤成. "Study of Hybrid Silicon Nanomaterials / Crystalline Silicon heterojunction Solar Cells." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/duc2ap.
Full textAbstract:
碩士國立虎尾科技大學
機械與機電工程研究所
96
In this thesis, the synthesized hybrid silicon nanomaterials (HSNMs) as the absorber layer of the thin-film solar cells have been developed by means of the vapor-liquid-solid (VLS) method. The HSNMs have been demonstrated using gold as the mediating catalyst and silane as the Si source ambient. The high quality HSNMs can be achieved by tuning the flow rate of the SiH4/N2/H2 and the time of the deposition. To increase the efficiency of the solar cell, the effects of the various processes on the solar cell were adopted and investigated, including (1) various gate electrodes (2) various thickness of the intrinsic silicon layer (3) the intrinsic silicon layer with and without hydrogen treatment (4) various thickness of the HSNMs (5) the HSNMs with and without hydrogen treatment. The results display that the densities and sizes of the HSNMs increase with increasing the thickness of the SiH4 gas flow. The morphology of the HSNMs can be affected by the flow ratio of nitrogen and hydrogen. Scanning electron microscopy image displays that the HSNMs with a diameter of several hundreds nanometer to 4 micrometer and a length of ~1-70 ?m were obtained. The Al gate electrode formed by sputter is better than that Ag gate electrode formed by printing. The optimum thickness of the intrinsic polysilicon layer and the HSNMs are around 50 nm and 5 min, respectively. The hydrogen treatment is helped for the characteristics of the intrinsic polysilicon layer and the HSNMs. According to the optimization of these process conditions, the efficiency of the Al/n+-HSNM/i-HSNM/i-poly-Si/p+-poly-Si structured thin-film solar cell can be achieved around 1.96%.
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Tai, Si-Po, and 戴錫坡. "Study of amorphous/crystalline silicon heterojunction solar cells." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/u8t8gn.
Full textAbstract:
碩士國立東華大學
電機工程學系
95
In this study we focus on the fabrication and characterization of amorphous (α-Si)/crystalline (c-Si) silicon heterojucntion solar cells. A very thin n-type amorphous emitter layer deposited on the top of the crystalline p-type silicon becomes the heterostucture solar cell. The impacts of the intrinsic buffer layer between n-type layer and p-type layer on the performance of heterostructure solar cells are investigated. The heterostructure solar cells with the intrinsic buffer layers obtain the high shunt resistance (Rsh) and large fill factor, but the low short-circuit current density. Due to the efficient surface passivation of the buffer layer on the p-type layer, the higher shunt resistance achieved for the p-i-n junction devices than that for p-n junction devices. The thick intrinsic buffer layers passivate the surface of crystal silicon layers, but leading to the high series resistance (Rs) and low short-circuit current density. The thick buffer layers also lead to the ”S” shaped J-V curves and low fill factor. Both p-n and p-i-n junction solar cells have been fabricated and studied. The p-n junction device obtains the high short-circuit current density (42.0mA/cm2) but low fill factor (41.6%), and the p-i-n junction device obtains the low short-circuit current density (29.8mA/cm2) but higher fill factor (56.6%). The efficiencies of 8.9% and 8.7% are achieved for the p-n and p-i-n junction solar cells, respectively.
47
Hsu, Wen-Tzu, and 許文慈. "Demonstration of Two-Metal Crystalline Silicon Solar Cells and Numerical Study of Microcrystalline Silicon Solar Cells." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/b6kh9y.
Full textAbstract:
碩士國立東華大學
光電工程學系
100
As time goes on, the development of the civilization became strong in the world, moreover, the energy source disappeared from the Earth. In order to keep the ecological balance of natural and technological, we make a choice for renewable energy. Solar energy is one of the most important energy source in the world. In this paper, we report the demonstration of two-metal crystalline silicon solar cells and numerical study of microcrystalline silicon solar cells by utilizing the simulation tool, Sentaurus TCAD for increasing the conversion efficiency. We used the p-type crystalline silicon as a substrate in this demonstration. Because the work function from metals are different, a built-in potential distribution in silicon can be formed for two-metal cells. Besides, the sample could achieve the effect of back surface field (BSF) via having graphite oxide on the bottom of substrate. The performance of two-metal crystalline silicon solar cell is better than control cell. For photovoltaic applications, microcrystalline Si has a lot of advantages, such as the ability to absorb the near-infrared part of the solar spectrum. However, there are many dangling bonds at the grain boundary in microcrystalline Si. These dangling bonds would lead to the recombination of photo-generated carriers and decrease the conversion efficiency. Hence, how to include the grain boundaries in the numerical study is important in order to simulate a microcrystalline Si solar cell accurately. We have successfully constructed a model considering the existed of grain boundary, and the simulation results are close to the reported data. In addition, a new structure - the three-terminal microcrystalline Si cell has been designed. The 3-μm-thick three-terminal cell can achieve a conversion efficiency of 10.8 %, while the efficiency of the typcial two-terminal cell is 9.7 %.
48
Saha, Sayan. "Cost effective high efficiency solar cells." Thesis, 2014. http://hdl.handle.net/2152/26934.
Full textAbstract:
To make solar energy mainstream, lower-cost and more efficient power generation is key. A lot of effort in the silicon photovoltaic industry has gone into using fewer raw materials (i.e., silicon) and using more inexpensive processing techniques and materials to reduce cost. Utilizing thinner substrates not only reduces cost, but improves cell efficiency provided both front and back surfaces are well-passivated. In the current work, a kerf-less process is developed in which ultra-thin (~25 [mu]m), flexible mono-crystalline silicon substrates can be obtained through an exfoliation technique from a thicker parent wafer. These substrates, when exfoliated, have thick metal backing which provides mechanical support to the thin silicon and enables ease of processing of the substrates for device fabrication. Optical, electrical, and reliability characterization studies for completed cells show this technology’s compatibility with a heterojunction solar cell process flow. Building on the promising results achieved on exfoliated substrates, further optimization work was carried out. Namely, an improved cleaning process was developed to remove front surface contamination on textured surfaces of exfoliated, flexible mono-crystalline silicon. This process is very effective at cleaning metallic and organic residues, without introducing additional contamination or degrading the supporting back metal used for ultra-thin substrate handling. Spectroscopic studies were performed to qualitatively and quantitatively understand the efficacy of different cleaning procedures in order to develop the new cleaning process. Results of the spectroscopic studies were further supported by comparing the electrical performance of cells fabricated with different cleans. To replace silver as contact metal with a cheaper substitute like nickel or copper, patterning and etching processes are generally used. A low-cost alternative is proposed, where a reusable shadow mask with a metal grid pattern is kept in contact with the surface of the substrate in a plasma-enhanced chemical vapor deposition chamber during silicon nitride deposition. This leaves a patterned silicon surface for selective metal growth by direct electro-deposition. The viability of this process flow is demonstrated by fabricating diffused junction n[superscript+]pp[superscript+] monofacial and bifacial cells and electrically characterizing them. Investigation of the factors limiting the efficiency of the cells was carried out by lifetime measurement experiments.text
49
Tan, Jason Tong Hoe. "Overcoming performance limitations of multi-crystalline silicon solar cells." Phd thesis, 2007. http://hdl.handle.net/1885/150119.
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Kao, Ming-Hsuan, and 高名璿. "Optimal Surface Nano Structure in Crystalline Silicon Solar Cells." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/89127942643988468447.
Full textAbstract:
碩士元智大學
光電工程研究所
99
Ｗe successfully form self-assemble ,close-packed and monolayer polystyrene nanospheres on the surface of silicon wafers, by employing simpley and cost-effectively spin-coating method. These nanospheres are used as sacrificial etching masks for reactive ion etching (RIE) process to fabricate different profile nano-arrays characterized as broadband antireflective and effective carrier collection structures for enhancing light harvesting of crystalline Si-based solar cells. Conventional antireflection layers were usually fabricated by depositing a single or multiple layers with restricted thickness and material selection on the silicon solar cells. However, the conventional method exhibited several drawbacks : 1. The stack of layers serve narrow-band antireflective properties. 2. Thermal mismatch and instability of the thin-film stacks have been the major obstacles to achieve broadband antireflection coatings. 3. Selection of materials with proper dielectric constants is difficult. According to the previous studies, the surface nano-arrays were reported to exhibit better broadband antireflective characteristics than the multiple antireflective layers, it opens up exciting opportunities for photovoltaic devices to further improve performance. In this project, we intend to demonstrate a high performance, large area Si solar cells by integrateing the antireflective nanostructure, We utilized rigorous coupled wave analysis (RCWA) method to calculate the reflectance of the nanostructured solar cells and desire to further optimize the light harvesting of the cells. In addition, implementation of the nanostructure will be conducted on silicon-based solar cells to reduce the broadband reflectance. After the RIE process, the samples with trapezoid structure were treated by dipping in HF:HNO3:H2O (2:48:50) solution to remove the damaged layer. This step is called defect removal etching (DRE). Not only the reflectance were reduced but also the lifetime was increased after DRE process. The data of lifetime and reflectance were input to APSYS simulator to calculate the short circuit current, open circuit voltage, and power conversion effeciency. The effeciency of trapezoid structures with DRE treatment achieve 15.51%, which shows an 16.53% compared to flat Si solar cells. We believe the trapezoid structures with DRE treatment are excellent anti-reflectance structures, which are promising candidates to realize the low-cost, high-efficiency solar cells.