Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Several aspects of the electrical properties of silicon grain boundaries have been studied. The temperature dependence of the zero-bias conductance and capacitance of single boundaries has been measured and shown to be in good agreement with a simple double depletion layer/thermal emission (DDL/TE) model developed to predict the transport properties of such structures. In addition, it has been shown that deconvolution of the I-V properties of some boundaries via a deconvolution scheme suggested by Pike and Seager yields effective one-electron densities of trapping states which are in good agreement with estimates obtained by low temperature electron emission measurements. Experiments have also been performed which indicate that diffusion of atomic hydrogen into silicon grain boundaries greatly reduces this density of trapping states. In properly prepared, large grained polycrystalline samples all measurable traces of grain boundary potential barriers can be removed to substantial penetration depths after several hours exposure to a hydrogen plasma at elevated temperatures. Initial experiments on prototype polysilicon solar cells have shown that this passivation process can improve AM1 efficiencies. In order to more fully understand and develop this process for improving practical multigrained cells, several device research efforts with other DOE/SERI funded contractors have been initiated.
Fundamental Studies of Grain Boundary Passivation in Polycrystalline Silicon with Application to Improved Photovoltaic Devices. A Final Research Report Covering Work Completed from February-December 1979
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Several aspects of the electrical properties of silicon grain boundaries have been studied. The temperature dependence of the zero-bias conductance and capacitance of single boundaries has been measured and shown to be in good agreement with a simple double depletion layer/thermal emission (DDL/TE) model developed to predict the transport properties of such structures. In addition, it has been shown that deconvolution of the I-V properties of some boundaries via a deconvolution scheme suggested by Pike and Seager yields effective one-electron densities of trapping states which are in good agreement with estimates obtained by low temperature electron emission measurements. Experiments have also been performed which indicate that diffusion of atomic hydrogen into silicon grain boundaries greatly reduces this density of trapping states. In properly prepared, large grained polycrystalline samples all measurable traces of grain boundary potential barriers can be removed to substantial penetration depths after several hours exposure to a hydrogen plasma at elevated temperatures. Initial experiments on prototype polysilicon solar cells have shown that this passivation process can improve AM1 efficiencies. In order to more fully understand and develop this process for improving practical multigrained cells, several device research efforts with other DOE/SERI funded contractors have been initiated.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Several aspects of the electrical properties of silicon grain boundaries have been studied. The temperature dependence of the zero-bias conductance and capacitance of single boundaries has been measured and shown to be in good agreement with a simple double depletion layer/thermal emission (DDL/TE) model developed to predict the transport properties of such structures. In addition, it has been shown that deconvolution of the I-V properties of some boundaries via a deconvolution scheme suggested by Pike and Seager yields effective one-electron densities of trapping states which are in good agreement with estimates obtained by low temperature electron emission measurements. Experiments have also been performed which indicate that diffusion of atomic hydrogen into silicon grain boundaries greatly reduces this density of trapping states. In properly prepared, large grained polycrystalline samples all measurable traces of grain boundary potential barriers can be removed to substantial penetration depths after several hours exposure to a hydrogen plasma at elevated temperatures. Initial experiments on prototype polysilicon solar cells have shown that this passivation process can improve AM1 efficiencies. In order to more fully understand and develop this process for improving practical multigrained cells, several device research efforts with other DOE/SERI funded contractors have been initiated.
Energy Research Abstracts
Solar Energy Update
Fundamental Studies of Grain Boundary Passivation in Polycrystalline Silicon with Application to Improved Photovoltaic Devices
Author: C. H. Seager
Publisher:
ISBN:
Category : Silicon crystals
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category : Silicon crystals
Languages : en
Pages :
Book Description
Fundamental Studies of Grain Boundary Passivation in Polycrystalline Silicon with Application to Improved Photovoltaic Devices. A Research Report Covering Work Completed from February 1981 to January 1982
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Grain boundary barrier heights and other properties were measured on a variety of Wacker poly-Si to test the contention of Redfield that as received samples had no potential barriers and that temperature anneals activate the impurities in the boundaries. Our results show that these generalizations are not true and that a variety of barrier behaviors are found. Several of our new analytical techniques for studying grain boundaries and their passivation have been upgraded, including a new cell for Fourier Transform Infrared (FTIR) studies, electrochemical techniques, and a laser scanning apparatus for imaging grain boundaries. Grain boundaries in a variety of samples have been successfully passivated by the use of both the Kaufman ion source and a dc discharge apparatus. 20% improvements in cell efficiencies have been observed in large grained poly-Si cells, and the time of treatment has been drastically reduced.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Grain boundary barrier heights and other properties were measured on a variety of Wacker poly-Si to test the contention of Redfield that as received samples had no potential barriers and that temperature anneals activate the impurities in the boundaries. Our results show that these generalizations are not true and that a variety of barrier behaviors are found. Several of our new analytical techniques for studying grain boundaries and their passivation have been upgraded, including a new cell for Fourier Transform Infrared (FTIR) studies, electrochemical techniques, and a laser scanning apparatus for imaging grain boundaries. Grain boundaries in a variety of samples have been successfully passivated by the use of both the Kaufman ion source and a dc discharge apparatus. 20% improvements in cell efficiencies have been observed in large grained poly-Si cells, and the time of treatment has been drastically reduced.
Government Reports Announcements & Index
Government Reports Annual Index
Author:
Publisher:
ISBN:
Category : Government reports announcements & index
Languages : en
Pages : 1642
Book Description
Publisher:
ISBN:
Category : Government reports announcements & index
Languages : en
Pages : 1642
Book Description
Crystalline Silicon Surface Passivation Using Aluminum Oxide: Fundamental Understanding and Application to Solar Cells
Author: Boris Adrian Veith-Wolf
Publisher:
ISBN: 9783843937085
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN: 9783843937085
Category :
Languages : en
Pages :
Book Description
Grain Boundary Passivation of Multicrystalline Silicon Using Hydrogen Sulfide as a Sulfur Source
Author: Arunodoy Saha
Publisher:
ISBN:
Category : Grain boundaries
Languages : en
Pages : 56
Book Description
Hydrogen sulfide (H2S) has been identified as a potential ingredient for grain boundary passivation of multicrystalline silicon. Sulfur is already established as a good surface passivation material for crystalline silicon (c-Si). Sulfur can be used both from solution and hydrogen sulfide gas. For multicrystalline silicon (mc-Si) solar cells, increasing efficiency is a major challenge because passivation of mc-Si wafers is more difficult due to its randomly orientated crystal grains and the principal source of recombination is contributed by the defects in the bulk of the wafer and surface. In this work, a new technique for grain boundary passivation for multicrystalline silicon using hydrogen sulfide has been developed which is accompanied by a compatible Aluminum oxide (Al2O3) surface passivation. Minority carrier lifetime measurement of the passivated samples has been performed and the analysis shows that success has been achieved in terms of passivation and compared to already existing hydrogen passivation, hydrogen sulfide passivation is actually better. Also the surface passivation by Al2O3 helps to increase the lifetime even more after post-annealing and this helps to attain stability for the bulk passivated samples. Minority carrier lifetime is directly related to the internal quantum efficiency of solar cells. Incorporation of this technique in making mc-Si solar cells is supposed to result in higher efficiency cells. Additional research is required in this field for the use of this technique in commercial solar cells.
Publisher:
ISBN:
Category : Grain boundaries
Languages : en
Pages : 56
Book Description
Hydrogen sulfide (H2S) has been identified as a potential ingredient for grain boundary passivation of multicrystalline silicon. Sulfur is already established as a good surface passivation material for crystalline silicon (c-Si). Sulfur can be used both from solution and hydrogen sulfide gas. For multicrystalline silicon (mc-Si) solar cells, increasing efficiency is a major challenge because passivation of mc-Si wafers is more difficult due to its randomly orientated crystal grains and the principal source of recombination is contributed by the defects in the bulk of the wafer and surface. In this work, a new technique for grain boundary passivation for multicrystalline silicon using hydrogen sulfide has been developed which is accompanied by a compatible Aluminum oxide (Al2O3) surface passivation. Minority carrier lifetime measurement of the passivated samples has been performed and the analysis shows that success has been achieved in terms of passivation and compared to already existing hydrogen passivation, hydrogen sulfide passivation is actually better. Also the surface passivation by Al2O3 helps to increase the lifetime even more after post-annealing and this helps to attain stability for the bulk passivated samples. Minority carrier lifetime is directly related to the internal quantum efficiency of solar cells. Incorporation of this technique in making mc-Si solar cells is supposed to result in higher efficiency cells. Additional research is required in this field for the use of this technique in commercial solar cells.
Solar Cells and Modules
Author: Arvind Shah
Publisher: Springer Nature
ISBN: 3030464873
Category : Science
Languages : en
Pages : 357
Book Description
This book gives a comprehensive introduction to the field of photovoltaic (PV) solar cells and modules. In thirteen chapters, it addresses a wide range of topics including the spectrum of light received by PV devices, the basic functioning of a solar cell, and the physical factors limiting the efficiency of solar cells. It places particular emphasis on crystalline silicon solar cells and modules, which constitute today more than 90 % of all modules sold worldwide. Describing in great detail both the manufacturing process and resulting module performance, the book also touches on the newest developments in this sector, such as Tunnel Oxide Passivated Contact (TOPCON) and heterojunction modules, while dedicating a major chapter to general questions of module design and fabrication. Overall, it presents the essential theoretical and practical concepts of PV solar cells and modules in an easy-to-understand manner and discusses current challenges facing the global research and development community.
Publisher: Springer Nature
ISBN: 3030464873
Category : Science
Languages : en
Pages : 357
Book Description
This book gives a comprehensive introduction to the field of photovoltaic (PV) solar cells and modules. In thirteen chapters, it addresses a wide range of topics including the spectrum of light received by PV devices, the basic functioning of a solar cell, and the physical factors limiting the efficiency of solar cells. It places particular emphasis on crystalline silicon solar cells and modules, which constitute today more than 90 % of all modules sold worldwide. Describing in great detail both the manufacturing process and resulting module performance, the book also touches on the newest developments in this sector, such as Tunnel Oxide Passivated Contact (TOPCON) and heterojunction modules, while dedicating a major chapter to general questions of module design and fabrication. Overall, it presents the essential theoretical and practical concepts of PV solar cells and modules in an easy-to-understand manner and discusses current challenges facing the global research and development community.