Download or read book The Effect of Grain Boundaries and Surface Damage on P n Junction Silicon Solar Cells written by Taher Daud and published by . This book was released on 1979 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Influence of Grain Boundaries on Recombination in Polysilicon Pn junction Solar Cells written by and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The physics controlling recombination in polysilicon pn-junction cells is described. Analytic models characterizing this recombination, whose parameters can be related directly to experiment, are developed. The analysis reveals that, in general, the description of intra-grain and grain-boundary recombination in a polysilicon solar cell requires the solution of a nonlinear, three-dimensional boundary-value problem. Cases of practical interest for which this problem is tractable are discussed. The analysis predicts an exp(qV/2kT) dependence (the reciprocal slope factor is exactly two) for carrier recombination at a grain boundary within the junction space-charge region of a non-illuminated, forward-biased cell. This result, and others of the analysis, are shown to be consistent with measured current-voltage characteristics of pn junctions fabricated on polycrystalline silicon.
Download or read book Solar Energy Update written by and published by . This book was released on 1980 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1979 with total page 1096 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration and published by . This book was released on 1976 with total page 988 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1981 with total page 1372 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Methods for Investigating the Properties of Polycrystalline Silicon P N Junction Solar Cells written by Jeffrey Alan Mazer and published by . This book was released on 1981 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A small-signal admittance method is developed for the determination of the grain-boundary surface-state distribution in the energy gap for that part of a grain boundary which has been preferentially diffused with phosphorus. various experimental attempts at suppressing the grain-boundary dark recombination current are described. It is shown that the large leakage currents of small polysilicon p-n junction mass diodes cause the measured I-V characteristics of those diodes to be of questionable value in analyzing the grain boundary component of the current.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1982 with total page 998 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Study of Grain Boundaries in Polycrystalline Thin film Solar Cells written by Bingrui Joel Li and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Silicon is one of the most studied semiconductor materials with techniques to control and manipulate its properties well established by the integrated circuit (IC) industry. While silicon wafer-based technology constitutes about 85% of the photovoltaics (PV) market, there are compelling reasons to develop thin-film solar cells. These include potential material cost and energy savings achievable with thin absorber layers of direct band-gap thin film materials, and the potential for incorporation of thin film PV onto inexpensive, flexible, or building material substrates, which opens up the possibility of new applications. Given the success of silicon wafer-based solar cells in the PV market, crystalline silicon on glass is a natural choice for thin-film PV technology. However, the efficiency of this technology is still too low to compete in the PV market. In fact, its record efficiency is only 10.5% which was achieved by CSG Solar. In order to boost the efficiency of this technology, we explore the use of ion-beam assisted deposition (IBAD) to create biaxially-textured silicon films which can potentially have less defects at the grain boundaries. Experimentally, we have fabricated an operational biaxially-textured silicon solar cell whose Voc is likely to have been affected by intra-grain defects as shown by our transmission electron microscopy (TEM) image. In order to investigate the interplay between grain boundary and intra-grain defects on solar cell performance and determine the potential benefits of developing biaxially-textured film solar cells, I used Synopsys' two-dimensional technology computer-aided design (TCAD) Sentaurus simulation tool. In general, the simulations found that biaxially-textured silicon solar cells improve solar cell efficiencies but there is small improvement for devices that have both large grains and low intra-grain carrier lifetime. Among the various thin-film technologies, CdTe and Cu(In, Ga)(S, Se)2 (CIGSSe), dominate the thin-film PV market. However in recent years, the photovoltaic community has seen growing interest in CZTS-based thin-film solar cells which include Cu2ZnSnS4 (CZTS), Cu2ZnSnSe4 (CZTSe) and Cu2ZnSn(S, Se)4 (CZTSSe) solar cells. This is driven by their potential to replace Cu(In, Ga)Se2 (CIGSe) and CdTe solar cells which face material scarcity, toxicity and market acceptance issues. In polycrystalline CIGSe-based (CIGSe, CISe, CuGaSe2 (CGSe)) and CdTe solar cells, grain boundaries do not seem to affect solar cell efficiency as much. In fact, some studies have identified grain boundaries as the source of high efficiency in polycrystalline CIGSe-based and CdTe solar cells. CIGSe-based and CZTS-based films are similar in terms of growth methods, optoelectronic and crystallographic properties. Because of these similarities and the benign nature of grain boundaries in CIGSe-based and CdTe films, it would be useful to examine the properties of grain boundaries in these materials. Using scanning Kelvin probe microscopy (SKPM) and conductive atomic force microscopy (C-AFM) techniques, I investigated the electronic properties of grain boundaries in CIGSe, CZTS and CZTSSe solar cells. SKPM measurements carried out in this work reveal a higher positive surface potential at the grain boundaries as compared to the grain while C-AFM measurements show higher current flow in the vicinity of the grain boundaries. These two measurement results are similar to those obtained for high quality CIGSe and CdTe and together they demonstrate the enhanced minority carrier collection taking place at the grain boundaries of CZTS and CZTSSe. Although SKPM measurement are susceptible to topographical and geometric effects, we believe that this effect is not dominating in our measurements as topography and surface potential profile lines are not exact mirror images of one another and regions of similar height have different potentials and vice versa. Nonetheless, I used a technique that involves photoreduction of AgNO3 to provide convincing evidence that our SKPM result is not a result of experimental artifacts but is truly indicative of the higher positive potential at the grain boundary. Having benign or beneficial grain boundaries have been found to be essential for achieving high efficiencies in polycrystalline CIGSe and CdTe solar cells. In my investigation, I found that high efficiency CZTS and CZTSSe solar cells have similar grain boundary electronic properties as high efficiency CIGSe and CdTe solar cells. As such, it might be possible for CZTS and CZTSSe solar cells to achieve similar high efficiencies as CIGSe and CdTe solar cells if other defects (intra-grain, surface and interfacial) are not limiting efficiencies.
Download or read book Grain Boundaries in Silicon Solar Cells written by and published by . This book was released on 1982 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The correlations between the electrical and compositional properties of grain boundaries in polycrystalline silicon (Si) are examined in detail. High-resolution surface analysis techniques (AES, SIMS, XPS, EELS) and microelectrical (SAM, EBIC, minority-carrier lifetime) characterization methods are used. The direct evidence for impurity segregation to the intergrain regions is presented. Effect of illumination on the grain boundary electrical characteristics are correlated with impurity compositions. Finally, the interrelationships among heat-treatment, oxygen segregation and grain boundary electrical activity are discussed.
Download or read book Spatially Resolved Studies of Grain Boundary Effects in Polycrystalline Solar Cells Using Micro Photoluminescence and Near Field Microscopy written by S. Smith and published by . This book was released on 2005 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photoluminescence and photocurrent spectroscopies combined with diffraction-limited and sub- diffraction-limited spatial resolution are achieved via micro-photoluminescence (m-PL) and near-field microscopy (NSOM). These methods are used to examine the photo-response of individual grain boundaries in thin-film, polycrystalline solar cells at room and cryogenic temperatures. A systematic m-PL study of the effect of CdCl2-treatment on recombination in CdTe/CdS solar cell structures of varying thickness directly reveals the grain-boundary and surface passivation action of this important post-growth processing step. We achieve 50nm (l/10) spatial resolution in near-field Optical Beam Induced Current imaging (n-OBIC) of polycrystalline silicon solar cells using NSOM, at varying stages of silicon nitride grain-boundary passivation, and measure lateral variations in photo-response of CdTe/CdS solar cells with subwavelength spatial resolution.
Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration. Technical Information Center and published by . This book was released on 1976 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy a Continuing Bibliography with Indexes written by and published by . This book was released on 1979 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Index to IEEE Publications written by Institute of Electrical and Electronics Engineers and published by . This book was released on 1995 with total page 1404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues for 1973- cover the entire IEEE technical literature.
Download or read book The Influence of Grain Boundaries on Solar Cell Performance written by and published by . This book was released on 1981 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grain boundary studies related to polycrystalline silicon solar cells are reviewed. Included in this paper are discussions of grain boundary effects, models and passivation methods. Major problem areas that need further studies are discussed.
Download or read book Cumulative Index to IEEE Photovoltaic Specialists Conferences 1962 1980 written by and published by . This book was released on 1980 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
