Download or read book Effects of Hydrogen Oxygen and Sulfur on The Performance of Cu In Ga Se2 Thin Film Solar Cells and Device Modeling by AMPS 1D Simulation written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Anticipated Performance of Cu In Ga Se2 Solar Cells in the Thin film Limit written by Ana Kanevce and published by . This book was released on 2007 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Sodium on Growth and Properties of Cu In Ga Se2 Thin Films and Solar Cells written by Dominik Rudmann and published by . This book was released on 2004 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optimisation of Cu In Ga Se 1tn2 Thin Film Solar Cells and Modules for Low Irradiance Conditions written by Alessandro Virtuani and published by . This book was released on 2004 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Device Physics of Cu In Ga Se2 Thin film Solar Cells written by Markus Gloeckler and published by . This book was released on 2005 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Physics of Cu In Ga Se2 Solar Cells and Their Layer Components written by Abedl-Rahman Ibdah and published by . This book was released on 2016 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycrystalline Cu(In1-xGax)Se2 (CIGS) thin film technology has emerged as a promising candidate for low cost and high performance solar modules. The efficiency of CIGS solar cells is strongly influenced by several key factors. Among these factors include Ga composition and its profile in the absorber layer, copper content in this layer, and the solar cell multilayer structure. As a result, tools for the characterization of thin film CIGS solar cells and their layer components are becoming increasingly essential in research and manufacturing. Spectroscopic ellipsometry is a non-invasive technique that can serve as an accurate probe of component layer optical properties and multilayer structures, and can be applied as a diagnostic tool for real-time, in-line, and off-line monitoring and analysis in small area solar cell fabrication as well as in large area photovoltaics manufacturing. Implementation of spectroscopic ellipsometry provides unique insights into the properties of complete solar cell multilayer structures and their layer components. These insights can improve our understanding of solar cell structures, overcome challenges associated with solar cell fabrication, and assist in process monitoring and control on a production line. In this dissertation research, Cu(In,Ga)Se2 films with different Cu contents have been prepared by the one stage co-evaporation process. These films have been studied by real time spectroscopic ellipsometry (RTSE) during deposition, and by in-situ SE at the deposition temperature as well as at room temperature to extract the dielectric functions (e1, e2) of the thin film materials. Analytical expressions for the room temperature dielectric functions were developed, and the free parameters that describe these analytical functions were in turn expressed as functions of the Cu content. As a result of this parameterization, the dielectric function spectra (e1, e2) can be predicted for any desired composition within the range of the samples investigated. This capability was applied for mapping the structural and compositional variations of CIGS thin films deposited over a 10 cm × 10 cm substrate area. In another application presented in this dissertation, a non-invasive method utilizing ex-situ spectroscopic ellipsometry analysis has been developed and applied to determine non-destructively the Ga compositional profile in CIGS absorbers. The method employs parameterized dielectric function spectra (e1, e2) of CIGS versus Ga content to probe the compositional variation with depth into the absorber. In addition, a methodology for prediction of the external quantum efficiency (QE) including optical gains and losses for a CIGS solar cell has been developed. The methodology utilizes ex-situ spectroscopic ellipsometry analysis of a complete solar cell, with no free parameters, to deduce the multilayer solar cell structure non-invasively and simulate optical light absorption in each of the layer components. In the case of high efficiency CIGS solar cells, with minimal electronic losses, QE spectra are predicted from the sum of optical absorption in the active layer components. For such solar cells with ideal photo-generated charge carrier collection, the SE-predicted QE spectra are excellent representation of the measured ones. Since the QE spectra as well as the short circuit current density (Jsc) can be calculated directly from SE analysis results, then the predicted QE from SE can be compared with the experimental QE to evaluate electronic losses based on the difference between the spectra. Moreover, the calculated Jsc can be used as a key parameter for the design and optimization of anti-reflection coating structures. Because the long term production potential of CIGS solar modules may be limited by the availability of indium, it becomes important to reduce the thickness of the CIGS absorber layer. Thickness reduction would reduce the quantity of indium required for production which would in turn reduce costs. A decrease in short-circuit current density (Jsc) is expected, however, upon thinning the CIGS absorber due to incomplete absorption. To clarify the limits of obtainable Jsc in ultra-thin CIGS solar cells with Mo back contacts, optical properties and multilayer structural data are deduced via spectroscopic ellipsometry analysis and used to predict the QE spectra and maximum obtainable Jsc values upon thinning the absorber. Moreover, SE-guided optical design of ultra-thin CIGS solar cells has been demonstrated. In the case of solar cells fabricated on Mo, thinning the absorber in a CIGS solar cell is associated with significant optical losses in the Mo containing back contact layers. This is due in part to the poor optical reflectance of Mo. Such optical losses may be reduced by employing a back contact design with improved reflectance. Thus, alternative novel solar cell structures with ultra-thin absorbers and improved back contact reflectance have been designed and investigated using SE and the optical modeling methods. In addition to optical losses, electronic losses in the ultra-thin solar cells have been evaluated. By separating the absorber layer into sub-layer regions (for example, near-junction, bulk, and near-back-contact) and varying carrier collection probability in these regions, the contribution of each region to the current can be estimated. Based on this separation, the origin of the electronic losses has been identified as near the back contact.

Download or read book A Theoretical Description of Thin Film Cu In Ga Se2 Solar Cell Performance written by Leonid A. Kosyachenko and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A Theoretical Description of Thin-Film Cu(In,Ga)Se2 Solar Cell Performance.

Download or read book New Deposition Process of Cu In Ga Se2 Thin Films for Solar Cell Applications written by Himal Khatri and published by . This book was released on 2009 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molybdenum (Mo) is currently the most common material used for Cu(In, Ga)Se2 solar cell back contacts. The first objective of this study is to utilize in-situ and ex-situ characterization techniques to investigate the growth, as well as the physical and chemical properties, of Mo thin films deposited by RF magnetron sputtering onto soda-lime glass (SLG) substrates. The effects of the deposition pressure on the nucleation and growth mechanisms that ultimately influence morphology and grain structure have been studied. Correspondence between real time spectroscopic ellipsometry (RTSE), X-ray diffraction (XRD), atomic force microscopy (AFM), and four-point probe resistivity measurements indicate that increasing deposition pressure leads to smaller average grain sizes and higher oxygen content in the Mo thin films. Changes of the material properties were also evaluated by changing RF power. It is observed that higher RF power, results in higher conductivity films. The second and overall objective of this work is to focus on the deposition and characterization of the Cu(In, Ga)Se2 absorber layer using the hybrid co-sputtering and evaporation process, which has potential for commercial PV. Solar cells were completed with a range of elemental compositions in the absorber layer, keeping a constant profile of Ga and varying Cu concentrations. The slightly Cu deficient Cu(In, Ga)Se2 films of band gap ~1.15 eV fabricated by this process consist of a single chalcopyrite phase and device efficiencies up to 12.4% were achieved for the composition ratios (x, y) = (0.30, 0.88). Correspondence between energy dispersive X-ray spectroscopy (EDS), X-ray diffraction, transmission and reflection (T & R), four-point probe resistivity, and current density-voltage (J-V) measurements indicate that increased Cu concentration leads to the incorporation of a secondary phase Cu2-xSe compound in the Cu(In, Ga)Se2 films, which is detrimental to cell performance. The third objective of this work is to evaluate the Cu2-xSe material properties by employing in-situ RTSE, as well as ex-situ SE and various other characterization techniques. SE revealed that the dielectric function spectra of Cu2-xSe evolve with temperature, providing insights into the evolution of transport properties and critical point structures. At room temperature, semi-metallic behavior of Cu2-xSe thin films was revealed by SE and Hall Effect measurements. These characteristics serve as key inputs for optical modeling of complex layer structures of Cu(In, Ga)Se2 films grown by 2- and 3-step processes.

Download or read book Effect of Cu deficient Layer Formation in Cu In Ga Se2 Solar cell Performance written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electro optical Modeling and Simulation of Cu In Ga Se S 2 Thin film Solar Cells written by and published by . This book was released on 2014 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Heat Treatments and Reduced Absorber Layer Thickness on Cu in Ga se2 Thin Film Solar Cells written by Vinodh Chandrasekaran and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The thickness of the Molybdenum back contact layer was increased to see if the amount of Sodium from the substrate had any effect on the device performance. The Ga/In ratio was altered and its effect was also studied. The 0.65um thick devices showed a large reduction in Voc̕s and Jsc̕s. The effect of Selenization time and Selenium flux during Selenization were studied at each of the different thicknesses.

Download or read book Impact of Cu In Ga Se2 Thin Film Growth Process on the Electrical Metastabilities of Related Solar Cell written by Tomasz Drobiazg and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Concepts for Cu In Ga Se2 Thin Film Solar Cells written by Sieghard Roman Seyrling and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of Cu In Ga Se2 Superstrate Thin Film Solar Cells written by and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Improvement of Cu In Ga S Se 2 Thin Film Solar Cells with the Help of Gallium and Sulfur Gradients written by Björn Jakob Müller and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spectrally Resolved Current Losses in Cu In Ga Se2 Thin film Solar Cells written by Jonas Lähnemann and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling Optical Properties of Thin Film Copper indium Gallium selenide Solar Cells Using Spectroscopic Ellipsometry written by Scott H. Stephens and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this research, the optical properties of Cu(In, Ga)Se 2 thin film solar cells were modeled using variable angle spectroscopic ellipsometry and compared against established optical data from bulk materials. Mo, MoSe 2, Cu(In, Ga)Se 2 and US films were measured individually as the devices were formed layer by layer. Optical data, thickness, surface roughness, and the methodology of preparing and effectively modeling samples have been determined. Diffusion of Na from the Soda Lime glass substrate is evident in the optical constants of the Mo layer. The optical constants of the MoSe 2 layer were found to be dependent upon the deposition conditions. The bandgap of the US layer was higher when deposited on Cu(In, Ga)Se 2 surfaces than when deposited on Mo. This implies that greater lattice strain is present in the US layer of solar cell devices than that of US films previously measured in CdS/Mo structures.