Download or read book Sintering of CU In Ga Se2 Nanocrystal Films for Photovoltaics written by Taylor Bryan Harvey and published by . This book was released on 2014 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low cost solar cells are needed to increase availability and reliability of electricity throughout the world. Spray deposition of Cu(In,Ga)Se2 (CIGS) nanocrystal inks is a promising route to low cost photovoltaics(PVs). CIGS nanocrystal inks have been used to fabricate solar cells with 3.1% power conversion efficiency (PCE) without any heat treatment, but are limited by poor charge transport. Sintering the nanocrystals into a polycrystalline film improves charge transport and device performance. Two sintering methods are investigated here: selenization and photonic curing. The nanocrystal films can be sintered by annealing the films in a Se environment, also known as selenization. The selenized device morphology and efficiency is influenced by the starting nanocrystal composition. A Se/Carbon layer deriving from the organic ligand decreases device efficiency, but is eliminated by annealing the nanocrystal films in Ar before the selenization treatment. In addition to eliminating the Se/Carbon layer, the pre-selenization anneal drives Na from the soda-lime glass substrate into the film and improves grain growth. Devices with efficiencies above 7.0% are fabricated using a multi-step deposition and sintering process. To simplify device fabrication, a single-step, scalable deposition is demonstrated using fully automated, ultrasonic spray coating. The ultrasonic spray deposition is highly sensitive to the nanocrystal ink organic content, and optimization of the nanocrystal synthesis wash procedure leads to highly uniform, reflective nanocrystal films. Devices fabricated from these films achieve 6.6% efficiency after selenization. The use of rapid pulses of broadband light, or photonic curing, is an alternative sintering method that is compatible with roll-to-roll fabrication and does not use high temperature processing. A wide range of pulse energy is used to treat nanocrystal films after spray deposition on three different back contact materials. Nanocrystal dewetting and agglomeration was observed after photonic curing of the films on a Mo contact, but is reduced significantly by using Au or MoSe2/Mo back contacts. Low energy pulses remove the organic capping ligand and bring the nanocrystals into close electrical contact, leading to devices exhibiting multiple exciton generation and extraction. Higher energy pulses sinter the nanocrystal layer and sintered nanocrystal photovoltaic devices are demonstrated.

Download or read book Copper Zinc Tin Sulfide Based Thin Film Solar Cells written by Kentaro Ito and published by John Wiley & Sons. This book was released on 2015-02-23 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beginning with an overview and historical background of Copper Zinc Tin Sulphide (CZTS) technology, subsequent chapters cover properties of CZTS thin films, different preparation methods of CZTS thin films, a comparative study of CZTS and CIGS solar cell, computational approach, and future applications of CZTS thin film solar modules to both ground-mount and rooftop installation. The semiconducting compound (CZTS) is made up earth-abundant, low-cost and non-toxic elements, which make it an ideal candidate to replace Cu(In,Ga)Se2 (CIGS) and CdTe solar cells which face material scarcity and toxicity issues. The device performance of CZTS-based thin film solar cells has been steadily improving over the past 20 years, and they have now reached near commercial efficiency levels (10%). These achievements prove that CZTS-based solar cells have the potential to be used for large-scale deployment of photovoltaics. With contributions from leading researchers from academia and industry, many of these authors have contributed to the improvement of its efficiency, and have rich experience in preparing a variety of semiconducting thin films for solar cells.

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 Smart Multifunctional Nano inks written by Ram K. Gupta and published by Elsevier. This book was released on 2022-10-26 with total page 728 pages. Available in PDF, EPUB and Kindle. Book excerpt: Smart Multifunctional Nano-inks: Fundamentals and Emerging Applications covers nano-inks and how they can be used in inkjet printers for printing complex circuitry on flexible substrates or as a paste for 3D printers. Microstructures can be 3D-printed using nano-inks in a combination of high-resolution plasma printing and subsequent rotogravure printing. In addition, smart multifunctional nano-inks are not only required for the electronic, but also in other applications, such as for secure inks, for currency, and in immigration documents. This book focuses on fundamental design concepts, promising applications, and future challenges of nano-inks in various areas, such as optoelectronics, energy, security and biomedical fields. The current challenge for the successful industrial application of nano-inks is in the preparation of a stable dispersion of advanced materials for nano-inks. The functionalization, synthesizing, and theoretical modeling provide the solution for most of the current issues, but there are still remaining challenges which are covered in this comprehensive resource. - Outlines the major nanomaterials used in the manufacture of smart nano-inks - Provides information on the major industrial applications of nano-inks - Assesses the major challenges of using nano-inks in a cost-effective way, and on an industrial scale

Download or read book Renewable Energy written by Bent Sorensen and published by Routledge. This book was released on 2018-12-14 with total page 2042 pages. Available in PDF, EPUB and Kindle. Book excerpt: This four-volume set, edited by a leading expert in the field, brings together in one collection a series of papers that have been fundamental to the development of renewable energy as a defined discipline. Some of the papers were first published many years ago, but they remain classics in their fields and retain their relevance to the understanding of current issues. The papers have been selected with the assistance of an eminent international editorial board. The set includes a general introduction and each volume is introduced by a new overview essay, placing the selected papers in context. The range of subject matter is considerable, including coverage of all the main renewable technologies, the fundamental principles by which they function, and the issues around their deployment such as planning, integration and socio-economic assessment. Overall, the set provides students, teachers and researchers, confronted with thousands of journal articles, book chapters and grey literature stretching back decades, with a ready-made selection of and commentary on the most important key writings in renewable energy. It will be an essential reference for libraries concerned with energy, technology and the environment.

Download or read book Growth and Characterisation of Cu In Ga Se2 Thin Films for Solar Cell Applications written by E. Ahmed and published by . This book was released on 1995 with total page 0 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 Fabrication of Cu In Ga Se2 and CuInS2 Photovoltaic Films and Scanning Electrochemical Microscopy of Different Semiconductor Films written by Jia Jia and published by . This book was released on 2012 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Elemental Distribution Microstructure and Optoelectronic Properties of Cu In Ga Se2 Thin Films for Solar Cells written by Enrico Avancini and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Simple Principle for In situ Composition Analysis of Cu In Ga Se2 Thin Films for Solar Cells and Its Application written by Holm Wiesner and published by . This book was released on 1996* with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of Alkaline doped Wide Bandgap Chalcopyrite Cu In Ga Se2 Thin Films and Solar Cells written by Setareh Zahedi-Azad and published by . This book was released on 2020* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin-film solar cells, Cu(In,Ga)Se2, recombination, open-circuit voltage, efficiency, simulation.

Download or read book Low cost Cu In Ga Se2 Absorbers from Nanosized Precursor Materials for Thin film Solar Cells written by Marc-Roland Kaelin and published by . This book was released on 2005 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book In Situ Investigation of the Rapid Thermal Reaction of Cu In Ga Precursors to Cu In Ga Se2 Thin film Solar Cell Absorbers written by Jan-Peter Bäcker 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 Advanced Precursor Reaction Processing for Ag alloyed Cu In Ga Se2 Solar Cells written by Sina Soltanmohammad and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Non vacuum Deposition of Cu In Ga Se2 Absorber Layers for Thin Film Solar Cells written by Alexander Roland Uhl and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Enhancement of the Deposition Processes of Cu In Ga Se2 and Cds Thin Films Via In situ and Ex situ Measurements for Solar Cell Application written by Vikash Ranjan and published by . This book was released on 2011 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin films of Cu(In, Ga)Se2 deposited by 1-stage, 2-stage and 3-stage co-evaporation processes result into the highest efficiency solar cells. Controlling the rate and sequences of individual sources during these co-evaporation processes are important for better quality Cu(In, Ga)Se2 absorber layers. At the same time, spectroscopic ellipsometry due to its ex-situ as well as in-situ application is considered as a very powerful tool to understand the material properties as well as to monitor the process. Nevertheless, spectroscopic ellipsometry was not properly utilized until now to characterize Cu(In, Ga)Se2 thin films. In this study, one of our goal is to understand the optical and electrical properties of Cu(In, Ga)Se2 as a function of process and composition. In the first part of this study, we implemented ex-situ spectroscopic ellipsometry (SE) along with other characterization techniques like Secondary ion mass spectroscopy (SIMS), Scanning electron microscopy (SEM), Auger electron spectroscopy (AES), x-ray diffraction (XRD), atomic force microscopy (AFM) etc. to compare Cu(In, Ga)Se2 thin films deposited by the above mentioned three co-evaporation processes. During this study, we were able to use SE to find the thickness, roughness, band gap, Ga grading of the Cu(In, Ga)Se2 deposited by 2-stage and 3-stage process. Finding of SE were correlated by SIMS, AES, SEM etc. In the case of Cu(In, Ga)Se2 deposited by 1-stage process, due to the high surface roughness, we are not able to implement the ex-situ spectroscopic ellipsometry. In the second and third part of this study, real time spectroscopic ellipsometry is implemented to study the material properties of Cu(In, Ga)Se2 thin films as a function of Cu and Ga concentration. Effectively, in a 3-stage co-evaporation process, the composition of the film changes during the process. To monitor and control the composition of Cu(In, Ga)Se2 during the 3-stage process by in-situ ellipsometry, it was necessary to understand the optical properties of Cu(In, Ga)Se2 as a function of Cu atomic percentage (at.%) as well as Ga at.%. Along with this, the inability to implement ex-situ SE for Cu(In, Ga)Se2 thin film motivated us to implement the spectroscopic ellipsometry in real time i.e. during the growth of the film. This in-situ real time application of SE helped us in understanding the micostructural evolution and dependence of the band gap with the Cu atomic percentage (at.%) as well as the Ga at.%. We also used this opportunity to understand the shift in the critical points as a function of temperature for CuInSe2 alloys. Characterization like AES, XRD, AFM etc were performed after the growth at room temperature to corroborate the RTSE findings. In the fourth and last part of this study, the growth of CdS on a Cu(In, Ga)Se2 surface as a function of time was studied using SE as well as AFM. We also used this opportunity to compare the growth of CdS on another substrate (SiO2). Spectroscopic ellipsometry and AFM revealed a quantum confinement effect in the case of CdS on SiO2 whereas no such effect was observed for CdS on Cu(In, Ga)Se2 surface due to the growth of compact CdS layers.

Download or read book Microstructure of Surface Layers in Cu In Ga Se2 Thin Films written by and published by . This book was released on 2003 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: In most Cu(In, Ga)Se2 thin films used for solar cells, there usually exist interfaces lying about 0.1 to 0.2 m below the surfaces. We report on a convergent-beam electron diffraction and energy-dispersive X-ray spectroscopy study of the microstructure and chemical composition of the surface region in Cu(In, Ga)Se2 thin films. We find that the surface region and the bulk are structurally similar, with no ordered defect chalcopyrite structure observed. However, their composition is slightly different, indicating that they can have different point-defect physics. Our results suggest that the subinterfaces and the bulk absorber may form homojunctions.