Advanced Characterization Techniques For Thin Film Solar Cells

The book focuses on advanced characterization methods for thin-film solar cells that have proven their relevance both for academic and corporate photovoltaic research and development. After an introduction to thin-film photovoltaics, highly experienced experts report on device and materials characterization methods such as electroluminescence analysis, capacitance spectroscopy, and various microscopy methods. In the final part of the book simulation techniques are presented which are used for ab-initio calculations of relevant semiconductors and for device simulations in 1D, 2D and 3D. Building on a proven concept, this new edition also covers thermography, transient optoelectronic methods, and absorption and photocurrent spectroscopy.

Polycrystalline thin-film solar cells have reached a levelized cost of energy that is competitive with all other sources of electricity. The technology has significantly improved in recent years, with laboratory cell efficiencies for cadmium telluride (CdTe), perovskites, and copper indium gallium diselenide (CIGS) each exceeding 22 percent. Both CdTe and CIGS solar panels are now produced at the gigawatt scale. However, there are ongoing challenges, including the continued need to improve performance and stability while reducing cost. Advancing polycrystalline solar cell technology demands an in-depth understanding of efficiency, scaling, and degradation mechanisms, which requires sophisticated characterization methods. These methods will enable researchers and manufacturers to improve future solar modules and systems.

Thin-film solar cells are either emerging or about to emerge from the research laboratory to become commercially available devices finding practical various applications. Currently no textbook outlining the basic theoretical background, methods of fabrication and applications currently exist. Thus, this book aims to present for the first time an in-depth overview of this topic covering a broad range of thin-film solar cell technologies including both organic and inorganic materials, presented in a systematic fashion, by the scientific leaders in the respective domains. It covers a broad range of related topics, from physical principles to design, fabrication, characterization, and applications of novel photovoltaic devices.

Cu(In1-xGax)Se2 Based Thin Film Solar Cells provides valuable contents about the fabrication and characterization of chalcopyrite Cu(In1-xGax)Se2 based thin film solar cells and modules. The growth of chalcopyrite Cu(In1-xGax)(S1-ySey)2 absorbers, buffers, window layers, antireflection coatings, and finally metallic grids, which are the sole components of solar cells, is clearly illustrated. The absorber, which contains multiple elements, segregates secondary phases if the growth conditions are not well optimized i.e., the main drawback in the fabrication of solar cells. More importantly the solutions for the growth of thin films are given in detail. The properties of all the individual layers and single crystals including solar cells analyzed by different characterization techniques such as SEM, AFM, XPS, AES, TEM, XRD, optical, photoluminescence, and Raman spectroscopy are explicitly demonstrated. The electrical analyses such as conductivities, Hall mobilities, deep level transient spectroscopy measurements etc., provide a broad picture to understand thin films or single crystals and their solar cells. The book clearly explains the working principle of energy conversion from solar to electrical with basic sciences for the chalcopyrite based thin film solar cells. Also, it demonstrates important criteria on how to enhance efficiency of the solar cells and modules. The effect of environmental factors such as temperature, humidity, aging etc., on the devices is mentioned by citing several examples. Illustrates a number of growth techniques to prepare thin film layers for solar cells Discusses characterization techniques such as XRD, TEM, XPS, AFM, SEM, PL, CL, Optical measurements, and Electrical measurements Includes I-V, C-V measurements illustrations Provides analysis of solar cell efficiency Presents current trends in thin film solar cells research and marketing

The fundamental concept of the book is to explain how to make thin film solar cells from the abundant solar energy materials by low cost. The proper and optimized growth conditions are very essential while sandwiching thin films to make solar cell otherwise secondary phases play a role to undermine the working function of solar cells. The book illustrates growth and characterization of Cu2ZnSn(S1-xSex)4 thin film absorbers and their solar cells. The fabrication process of absorber layers by either vacuum or non-vacuum process is readily elaborated in the book, which helps for further development of cells. The characterization analyses such as XPS, XRD, SEM, AFM etc., lead to tailor the physical properties of the absorber layers to fit well for the solar cells. The role of secondary phases such as ZnS, Cu2-xS,SnS etc., which are determined by XPS, XRD or Raman, in the absorber layers is promptly discussed. The optical spectroscopy analysis, which finds band gap, optical constants of the films, is mentioned in the book. The electrical properties of the absorbers deal the influence of substrates, growth temperature, impurities, secondary phases etc. The low temperature I-V and C-V measurements of Cu2ZnSn(S1-xSex)4 thin film solar cells are clearly described. The solar cell parameters such as efficiency, fill factor, series resistance, parallel resistance provide handful information to understand the mechanism of physics of thin film solar cells in the book. The band structure, which supports to adjust interface states at the p-n junction of the solar cells is given. On the other hand the role of window layers with the solar cells is discussed. The simulation of theoretical efficiency of Cu2ZnSn(S1-xSex)4 thin film solar cells explains how much efficiency can be experimentally extracted from the cells. One of the first books exploring how to conduct research on thin film solar cells, including reducing costs Detailed instructions on conducting research

This book examines the electronic structure of earth-abundant and environmentally friendly materials for use as absorber layers within photovoltaic cells. The corroboration between high-quality photoemission measurements and density of states calculations yields valuable insights into why these materials have demonstrated poor device efficiencies in the vast literature cited. The book shows how the materials’ underlying electronic structures affect their properties, and how the band positions make them unsuitable for use with established solar cell technologies. After explaining these poor efficiencies, the book offers alternative window layer materials to improve the use of these absorbers. The power of photoemission and interpretation of the data in terms of factors generally overlooked in the literature, such as the materials’ oxidation and phase impurity, is demonstrated. Representing a unique reference guide, the book will be of considerable interest and value to members of the photoemission community engaged in solar cell research, and to a wider materials science audience as well.

The book is devoted to the spatial characterization of solar cells and PV modules. It is written both as a monograph as well as a succinct guide for the state-of-the-art spatial characterization techniques and approaches. Amongst the approaches discussed are visual imaging, electro- and photo-luminescence imaging, thermography, and light beam induced mapping techniques. Emphasis is given on the luminescence image acquisition and interpretation due to its great potential. Characterization techniques are accompanied by simulation tools. The contents are aimed at a readership of students and senior researchers in R&D as well as engineers in industry who are newcomers to the spatial characterization of either solar cells or PV modules. The concepts and approaches presented herein are based on but not limited to case studies of real thin-film PV devices. Key features:  Review of spatially resolved characterization techniques and accompanying SPICE simulations in photovoltaics  Use of spatially resolved characterization techniques and their combinations for the identification of inhomogeneities in small area CdTe and dye-sensitized solar cells  Case studies of electroluminescence imaging of commercial PV modules (c-Si, CIGS, CdTe, a-Si, tandem and triple junction thin-film-Si) The contents are aimed at a readership of students and senior researchers in R&D as well as engineers in industry who are newcomers to the spatial characterization of either solar cells or PV modules. The concepts and approaches presented herein are based on but not limited to case studies of real thin-film PV devices. Key features:  Review of spatially resolved characterization techniques and accompanying SPICE simulations in photovoltaics  Use of spatially resolved characterization techniques and their combinations for the identification of inhomogeneities in small area CdTe and dye-sensitized solar cells  Case studies of electroluminescence imaging of commercial PV modules (c-Si, CIGS, CdTe, a-Si, tandem and triple junction thin-film-Si)

Characterization Techniques for Perovskite Solar Cell Materials: Characterization of Recently Emerged Perovskite Solar Cell Materials to Provide an Understanding of the Fundamental Physics on the Nano Scale and Optimize the Operation of the Device Towards Stable and Low-Cost Photovoltaic Technology explores the characterization of nanocrystals of the perovskite film, related interfaces, and the overall impacts of these properties on device efficiency. Included is a collection of both main and research techniques for perovskite solar cells. For the first time, readers will have a complete reference of different characterization techniques, all housed in a work written by highly experienced experts. Explores various characterization techniques for perovskite solar cells and discusses both their strengths and weaknesses Discusses material synthesis and device fabrication of perovskite solar cells Includes a comparison throughout the work on how to distinguish one perovskite solar cell from another