Download or read book Development of in situ methods for process monitoring and control and characterization of Cu Zn Sn S based thin films written by Van Duren, Stephan and published by Universitätsverlag der TU Berlin. This book was released on 2019-06-03 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, kesterite Cu2ZnSnS4 (CZTS) has become an interesting alternative to copper indium gallium (di)selenide (CIGS) due to its non-toxic and earth abundant constituents. A variety of methods is being used to fabricate kesterite thin films, such as coevaporation, sputtering, electrodeposition, spray pyrolysis and others. Most of them include an annealing step to stimulate elemental mixing and interdiffusion. Although conversion efficiencies of kesterite solar cells have increased among different research groups, the record value of 12.6% set by IBM in 2014 has not been broken yet. Therefore, experimental and theoretical studies are needed to predict the effect of the secondary phases and detrimental defects on the electronical properties of the CZTS based solar devices. The work presented here studies non-destructive techniques for in situ process control and monitoring. With the aim to detect phases and phase transitions to optimize crucial processing steps such as pre-annealing of metal precursors, high temperature annealing and vacuum deposition of Cu-Sn-Zn-S based thin films. The research consists of three parts in which Raman spectroscopy, X-ray diffraction (XRD) and reflectometry are used to explore this objective. In the first part Raman spectroscopy is investigated as an in situ monitoring technique during high temperature annealing of thin films. It investigates whether the occurrence of CZTS can be monitored when it is created from annealing a Mo/CTS/ZnS layered thin film. CuS, SnS, ZnS and CTS (Cu-Sn-S) films are prepared by physical vapor deposition. The Raman scattering intensity was compared to investigate whether their specific vibrational modes can be distinguished from each other at room temperature. Then, the CTS film is annealed between 50 and 550 °C in order to investigate whether CTS vibrational modes can be identified at elevated temperatures and to see which transitions take place within the thin film. Also, a CZTS reference film is annealed between 50 and 550 °C for reference purposes. The temperature dependence of the main CZTS modes is examined to investigate whether it can be used for in situ temperature control. Finally, a ZnS layer is deposited on the unannealed CTS film to obtain a Mo/CTS/ZnS layered film. This film is used to study the conversion of CTS/ZnS into CZTS at elevated temperatures. It was found that Raman spectroscopy can successfully be used to monitor formation of CZTS by identifying its main vibrational mode during the annealing process. The intensity of the CTS modes reduces at elevated temperatures. At 450 °C, the main CZTS mode at 338 cm-1 can be clearly identified. The second part also focuses on high temperature annealing. However, in this part the focus lies on annealing of the metal precursor films. It is explored whether specific alloys benefit or hinder the formation of secondary phases during formation of the CZTS absorber films. Also, to what extent this influences solar cell performance. In situ XRD was investigated for in situ monitoring of the pre-annealing process. Cu-poor metal precursor films are prepared by sputtering deposition. The precursors are annealed at 150 °C, 200 °C, 300 °C and 450 °C in a three zone tube furnace. The effect on the structural properties is analysed by XRD to study the formation mechanism of alloys. The precursor films are then sulfurized in a three zone tube furnace. The structural properties of the absorber are analysed and correlated with structures in the precursor. It is found that formation of SnS2 in the absorber is proportional to the remaining Sn in the pre-annealed precursor. Also, electron micrographs showed that pre-annealing temperature influences grain growth and surface precipitation of Sn-S and Zn-S. Pre-annealed absorbers at 450 °C did not exhibit these phases on the surface. Solar devices are fabricated from the absorber films and best performing devices were obtained from pre-annealed absorbers at 450 °C. They showed absence of Sn and SnS2 in, respectively, the precursor and absorber. It could be concluded that SnS2 phases are detrimental to device efficiency and that SnS2 XRD peak intensity follows an inverse proportionality with device efficiency. The third part explores reflectometry as a method to monitor a growing film during thermal evaporation in a physical vapor deposition (PVD) system. A set of six CZTS absorbers is examined by ex situ Raman spectroscopy and reflectometry to study the influence of secondary phases CuS and ZnS on reflection spectra. Composition strongly influences reflection spectra and CuS leaves a characteristic dip in the reflection spectrum at about 600 nm. An integration method was used to analyze this phenomenon quantitatively. Subsequently, a reflectometry setup is designed, developed and integrated in the PVD system. Four different CZTS co-evaporated and multi-layered films are deposited. Structural, morphological and vibrational properties are investigated. The reflection spectra are monitored during deposition and time-dependent reflection spectra are analyzed for characteristic aspects related to properties such as thickness, band gap and phase formation. CuS could not be detected in the films by the integration method due to the superposition of the CuS dip with developing interference fringes during film growth. However, in multilayered CTS/ZnS film it is found that the onset of ZnS deposition can be detected by increased reflection intensity due to reduced surface roughness. Additionally, the shifting onset of the interference fringes to lower photon energies can be used as a characteristic fingerprint during the deposition process. In conclusion, this work showed that Raman spectroscopy, XRD and reflectometry could be successfully implemented for in situ process control and monitoring of high temperature annealing and vacuum deposition of Cu-Sn-Zn-S based precursors and absorbers. The application of these in situ techniques can lead to the optimization of thin film material properties and solar cells. As such, this study has paved the way for further improvement of Cu-Sn-Zn-S based precursors and thin film absorbers. Innerhalb der letzten Jahre hat sich Kesterit Cu2ZnSnS4 (CZTS) aufgrund seiner ungiftigen Bestandteile und deren hoher Verfügbarkeit zu einer interessanten Alternative zu Kupfer Indium Gallium (di-)Selenid (CIGS) entwickelt. Zur Herstellung von Kesterit Dünnschichten wird eine Vielzahl von Methoden verwendet wie Ko-Verdampfung, Sputtern, Elektrodeposition, Spray Pyrolyse und andere. Die meisten davon beinhalten einen Temper-Schritt um die Durchmischung und Interdiffusion der Elemente zu stimulieren. Obwohl der Wirkungsgrad der Kersterit Solarzellen von verschiedenen Forschungsgruppen erhöht wurde, ist der Rekordwert von IBM von 12,6 % noch nicht gebrochen worden. Daher werden experimentelle und theoretische Studien benötigt, die den Einfluss von Fremdphasen und schädlichen Defekten auf die elektronischen Eigenschaften der CZTS Solarzellen vorhersagen. Die vorliegende Arbeit untersucht zerstörungsfreie Methoden für die in situ Prozesskontrolle und -überwachung. Dabei ist das Ziel, entscheidende Prozessschritte wie das Vortempern der Metall-Vorläufer sowie das Hochtemperatur-Tempern und die Vakuum-Abscheidung von Cu-Sn-Zn-S basierten Schichten zu optimieren. Die Untersuchung besteht aus drei Teilen, in denen Raman-Spektroskopie, Röntgendiffraktion (XRD) und Reflektometrie benutzt werden um dieses Ziel zu erreichen. Im ersten Teil wird die Ramanspektroskopie als in situ Methode zur Überwachung des Hochtemperatur-Temperns von Dünnschichten betrachtet. Es wird untersucht, ob das Entstehen von CZTS beim Tempern von gestapelten Mo/CTS/ZnS Dünnschichten beobachtet werden kann. CuS, SnS, ZnS und CTS (Cu-Sn-S) Schichten werden durch physikalische Gasabscheidung hergestellt. Die Intensität der Raman Streuung wurde vergleichen um zu untersuchen, ob die spezifischen Vibrations-Moden bei Raumtemperatur voneinander unterschieden werden können. Dann werden die CTS Schichten zwischen 50 °C und 550 °C getempert um zu untersuchen, ob die CTS Vibrations-Moden bei höheren Temperaturen identifiziert werden können und um festzustellen, welche Übergänge innerhalb der Schicht auftreten. Außerdem wurde eine CZTS Referenzschicht zwischen 50 °C und 550 °C für Referenzzwecke getempert worden. Die Temperaturabhängigkeit der CZTS Haupt-Moden werden betrachtet, um zu untersuche, ob sie für die in situ Temperaturüberwachung verwendet werden können. Abschließend wurde eine ZnS Schicht auf einem nicht getemperten CTS Film abgeschieden, um eine gestapelte Mo/CTS/ZnS Schicht zu erhalten. Diese Schicht wird verwendet, um die Umwandlung von CTS/ZnS zu CZTS bei erhöhten Temperaturen zu untersuchen. Es wurde festgestellt, dass Raman Spektroskopie erfolgreich verwendet werden kann, um die Bildung von CZTS zu überwachen, indem die Haupt-Vibrations-Moden während des Temperns identifiziert werden. Die Intensität der CTS Moden verringert sich bei höheren Temperaturen. Bei 450 °C kann die CZTS Hauptmode bei 338 cm-1 klar identifiziert werden. Der zweite Teil konzentriert sich ebenfalls auf das Hochtemperatur-Tempern. In diesem Teil liegt der Fokus allerdings auf dem Tempern der Metal-Vorläufer-Schichten. Es wird erforscht, ob bestimmte Legierungen die Entstehung von Fremdphasen während der Entstehung der CZTS Absorberschichten begünstigen oder hemmen und welchen Einfluss dies auf die Leistung der Solarzelle hat. In situ XRD wird verwendet, um die Prozesse des Vortemperns zu überwachen. Kupfer arme Metall-Vorläufer-Schichten werden durch Sputtern aufgetragen. Die Vorläufer werden bei 150 °C, 200 °C, 300 °C und 450 °C in einem Drei-Zonen-Röhren-Ofen getempert. Die Auswirkungen auf die strukturellen Eigenschaften werden mit XRD analysiert, um den Entstehungsmechanismus der Legierungen zu untersuchen. Die Vorläuferschichten werden dann in einem Drei-Zonen-Röhren-Ofen sulfurisiert. Die strukturellen Eigenschaften des Absorbers werden analysiert und mit der Struktur der Vorläufer korreliert. Es wurde festgestellt, dass die Entstehung von SnS2 im Absorber proportional zum verbleibenden Sn im vorgetemperten Vorläufer ist. Außerdem zeigen Bilder des Rasterelektronenmikroskops, dass die Temperatur des Vortemperns das Kornwachstum und das Abschieden von Sn-S und Zn-S an der Oberfläche beeinflusst. Bei 450 °C vorgetemperte Absorber weisen keine dieser Phasen an der Oberfläche auf. Solarzellen werden aus diesen Absorber-Schichten hergestellt und die besten Zellen entstanden aus den bei 450 °C vorgetemperten Absorbern. Bei diesen traten Sn und SnS2 weder im Vorläufer noch im Absorber auf. Es konnte geschlussfolgert werden, dass SnS2 Phasen schädlich für den Wirkungsgrad der Zellen sind und dass die Intensität der SnS2 XRD Peaks invers proportional zum Wirkungsgrad der Zellen ist. Der dritte Teil erforscht die Reflektometrie als Methode zur Überwachung des Schichtwachstums während des thermischen Verdampfens in einer Anlage zur physikalischen Gasabscheidung (PVD). Ein Satz aus sechs CZTS Absorbern wird mittels ex situ Raman-Spektroskopie und Reflektometrie vermessen, um den Einfluss der Fremdphasen CuS und ZnS auf die Reflexionsspektren zu untersuchen. Die Zusammensetzung beeinflusst die Reflexionsspektren stark und CuS hinterlässt eine charakteristische Senkung bei 600 nm im Reflexionsspektrum. Eine Integrationsmethode wurde verwendet um dieses Phänomen quantitativ zu analysieren. Anschließend wurde ein Reflektometrieaufbau entworfen, entwickelt und in die PVD-Anlage integriert. Vier verschiedene CZTS koverdampfte und Mehrschicht-Filme wurden abgeschieden. Strukturelle, morphologische und Vibrationseigenschaften werden untersucht. Die Reflexionsspektren werden während des Abscheidens aufgenommen und zeitabhängige Reflexionsspektren werden auf charakteristische Aspekte im Zusammenhang mit Eigenschaften wie Dicke, Bandlücke und Entstehung von Phasen untersucht. CuS konnte in den Schichten mit der Integrations-Methode wegen der Überlagerung der CuS Senkung mit dem entstehenden Interferenzmuster nicht detektiert werden. Allerdings wurde in gestapelten CTS/ZnS Schichten beobachtet werden, dass der Beginn der ZnS Abscheidung durch eine ansteigende Intensität der Reflektion aufgrund der verringerten Oberflächenrauigkeit detektiert werden kann. Zusätzlich kann die Verschiebung des Startpunkts der Interferenzen zu niedrigeren Photonenenergien als charakteristischer Fingerabdruck während des Abscheidungsprozesses verwendet werden. Zusammenfassend zeigt diese Arbeit, dass Raman-Spektroskopie, XRD und Reflektrometrie erfolgreich als in situ Prozesskontrolle und –überwachung bei Hochtemperatur-Tempern und Vakuum-Abscheidung von Cu-Sn-Zn-S basierten Vorläufern und Absorbern realisiert werden konnten. Die Anwendung dieser in situ Techniken kann zu einer Optimierung der Eigenschaften von Dünnschicht-Materialien und von Solarzellen führen. Als solche hat diese Untersuchung den Weg für weitere Verbesserung von Cu-Sn-Zn-S basierte Vorläufer und Dünnschicht-Absorber geebnet.

Download or read book Photoinduced thiol ene click chemistry assisted additive manufacturing and freeze casting of polymer derived ceramics written by Wang, Xifan and published by Universitätsverlag der TU Berlin. This book was released on 2019-09-30 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymer-derived ceramics possess great advantages in the view of cellular ceramic processing compared to traditional powder-based technologies, as the polymeric nature of ceramic precursors allows the utilization of various shaping approaches. Amongst them, Additive Manufacturing and Freeze Casting are two novel shaping methods, which are capable of producing three-dimensional complex architectures and foams with well-controlled pore morphology, respectively. In this thesis, photoinduced thiol-ene polymerization of vinyl containing preceramic polymers with thiol monomers is systematically investigated, both from the energetic view and from the kinetic view. Subsequently, a novel stereolithographic approach is developed and applied to the additive manufacturing of complex-shaped polymer-derived ceramics. In addition, photopolymerization-assisted freeze casting is successfully developed to freeze cast liquid preceramic polymer and yields porous ceramics with well-controlled pore morphology. Polymerabgeleitete Keramiken besitzen große Vorteile im Hinblick auf den Verarbeitungsprozess von zellularen Keramiken im Vergleich zu traditionellen pulverbasierten Technologien, da der polymere Ursprung der Ausgangsstoffe für die Keramik die Nutzung verschiedener Formgebungsmethoden ermöglicht. Additive Fertigung und Gefriergießen sind zwei neuartige Formgebungsverfahren, die jeweils in der Lage sind, komplexe dreidimensionale Geometrien sowie Schäume mit einer kontrollierten Porenmorphologie zu produzieren. In dieser Arbeit wird die photoinduzierte Thiol-En-Polymerisation von prekeramischen Polymeren, die Vinyl und Thiol-Monomere enthalten, systematisch und sowohl aus energetischer als auch aus kinetischer Hinsicht untersucht. Im Folgenden wird ein neuartiger stereolithografischer Ansatz entwickelt und auf die additive Fertigung von polymerabgeleiteten Keramiken komplexer Gestalt angewendet. Zusätzlich wird photopolymerisierungsunterstütztes Gefriergießen erfolgreich entwickelt, um flüssige prekeramische Polymere gefrierzugießen und poröse Keramiken mit einer definierten Porenmorphologie zu erzeugen.

Download or read book Advanced Characterization Techniques for Thin Film Solar Cells written by Daniel Abou-Ras and published by John Wiley & Sons. This book was released on 2016-07-13 with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book In Situ Real Time Characterization of Thin Films written by Orlando Auciello and published by John Wiley & Sons. This book was released on 2001 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: An in-depth look at the state of the art of in situ real-time monitoring and analysis of thin films With thin film deposition becoming increasingly critical in the production of advanced electronic and optical devices, scientists and engineers working in this area are looking for in situ, real-time, structure-specific analytical tools for characterizing phenomena occurring at surfaces and interfaces during thin film growth. This volume brings together contributed chapters from experts in the field, covering proven methods for in situ real-time analysis of technologically important materials such as multicomponent oxides in different environments. Background information and extensive references to the current literature are also provided. Readers will gain a thorough understanding of the growth processes and become acquainted with both emerging and more established methods that can be adapted for in situ characterization. Methods and their most useful applications include: * Low-energy time-of-flight ion scattering and direct recoil spectroscopy (TOF-ISRAS) for studying multicomponent oxide film growth processes * Reflection high-energy electron diffraction (RHEED) for determining the nature of chemical reactions at film surfaces * Spectrometric ellipsometry (SE) for use in the analysis of semiconductors and other multicomponent materials * Reflectance spectroscopy and transmission electron microscopy for monitoring epitaxial growth processes * X-ray fluorescence spectroscopy for studying surface and interface structures * And other cost-effective techniques for industrial application

Download or read book Growth Characterization and Applications of Zinc Sulfide Thin Films by Solution Based Processes written by Dick Chiu and published by . This book was released on 2017 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zinc Sulfide (ZnS) thin film, with a wide band gap, has been used for many applications, such as buffer layer for CIGS solar cells, light emitting diodes and thin film electroluminescent devices. In this work, ZnS thin films were prepared using two different deposition processes. In the first method, ZnS thin films were deposited by using conventional chemical bath deposition (CBD) process. Micro-reactor assisted solution deposition (MASD) with a flow cell was used as the second method. Growth kinetics of ZnS thin films in CBD was analyzed using in-situ quartz crystal microbalance measurements, and ex-situ transmission electron microscopy (TEM) and scanning electron microscopy (SEM) measurements. The results from the TEM and SEM measurements suggest that the film growth follows a two-step process with the formation of the nuclei in the solution first, attachment to the surface, followed by aggregation of nanoparticles into half spheres on the surface of the substrate and finally half spheres connect to the neighbor half spheres, thereby forming a continuous film. The mechanism study, verified by the SEM images, shows that nucleation starts very early in the CBD process. The degree of supersaturation influences the growth rate and final surface morphology. Temperature-dependent growth rate in the linear growth region follows the Arrhenius equation with an estimated value of activation energy (Ea) to be around 36 KJ/mol. This value, which is considered low (less than 40 kJ/mol), indicates that the rate limiting step is more likely to be a physical process such as adsorption or diffusion, rather than a chemical process, which tends to have higher activation energies. In our study, the chemical bath is vigorously stirred so that the rate-limiting step is likely controlled by a physically adsorption mechanism. The continuous flow micro reactor was used to deposit ZnS thin films using various flow cells of different designs. The depositions were carried out on display glass of 1 inch wide by 3 inches long. Both analytical equations (Hagen-Poiseuille) and computational fluid dynamics were applied to determine proper height for the flow channel. COMSOL Multiphysics simulation of fluid flow along with particle tracer was carried out to find an optimum cut out radius for further study. The film thickness growth kinetics and solute concentration near the substrate surface was simulated using the COMSOL Multiphysics program with an assumption of laminar flow, transport of diluted species and a simplified first order reaction. An insert that mimics a cut out radius of 2.31 inches was fabricated using a 3D printer and installed in the flow cell to deposit ZnS thin films. ZnS thin films deposited using the flow cells with and without the 3D printed insert were investigated. The results were analyzed using plane-view and cross-sectional SEM images. The film thickness was determined by cross-sectional SEM image. The results indicated that the thickness uniformity was improved with the 3D printed insert. We found toward the end of the substrate, the ZnS thin film was not continuous due to the lower solution concentration caused by the depletion of reactants. New flow cell designs were proposed and COMSOL simulation was performed to examine the effectiveness of these flow cells. To demonstrate the utility of the ZnS thin films by solution-based processes, SnS and CuS thin films were deposited on top of the ZnS thin film to form SnS/CuS/ZnS layered precursor film then followed by selenziation at various temperatures in an attempt to produce CZTSSe absorber layers for CZTSSe thin film solar cells.

Download or read book Copper Zinc Tin Sulfide Thin Films for Photovoltaics written by Jonathan J. Scragg and published by Springer Science & Business Media. This book was released on 2011-09-01 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Jonathan Scragg documents his work on a very promising material suitable for use in solar cells. Copper Zinc Tin Sulfide (CZTS) is a low cost, earth-abundant material suitable for large scale deployment in photovoltaics. Jonathan pioneered and optimized a low cost route to this material involving electroplating of the three metals concerned, followed by rapid thermal processing (RTP) in sulfur vapour. His beautifully detailed RTP studies – combined with techniques such as XRD, EDX and Raman – reveal the complex relationships between composition, processing and photovoltaic performance. This exceptional thesis contributes to the development of clean, sustainable and alternative sources of energy

Download or read book The Role of Interparticle Heterogeneities in the Selenization Pathway of Cu Zn Sn S Nanoparticle Thin Films written by and published by . This book was released on 2015 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Real-time energy dispersive x-ray diffraction (EDXRD) analysis has been utilized to observe the selenization of Cu-Zn-Sn-S nanoparticle films coated from three nanoparticle populations: Cu- and Sn-rich particles roughly 5 nm in size, Zn-rich nanoparticles ranging from 10 to 20 nm in diameter, and a mixture of both types of nanoparticles (roughly 1:1 by mass), which corresponds to a synthesis recipe yielding CZTSSe solar cells with reported total-area efficiencies as high as 7.9%. The EDXRD studies presented herein show that the formation of copper selenide intermediates during the selenization of mixed-particle films can be primarily attributed to the small, Cu- and Sn-rich particles. Moreover, the formation of these copper selenide phases represents the first stage of the CZTSSe grain growth mechanism. The large, Zn-rich particles subsequently contribute their composition to form micrometer-sized CZTSSe grains. In conclusion, these findings enable further development of a previously proposed selenization pathway to account for the roles of interparticle heterogeneities, which in turn provides a valuable guide for future optimization of processes to synthesize high quality CZTSSe absorber layers.

Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 2304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metals Abstracts written by and published by . This book was released on 1997 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Growth Characterizations and Applications of Copper Sulfide Thin Films by Solution based Processes written by Paravee Vas-Umnuay and published by . This book was released on 2013 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: Copper sulfides (Cu[subscript x]S) are compound semiconductor materials that exhibit considerable optical and electrical properties varying significantly as a function of the composition. Copper sulfide thin films can be used in many applications, such as solar control coatings, solar cells, photothermal conversion of solar energy, electroconductive coatings, and microwave shielding coatings. A variety of solution-based and vapor-based techniques are suitable for their deposition. Solution-based processes have the advantages of simplicity, low capital cost, and low processing temperature. In this work, copper sulfide thin film deposition by a number of solution-based processes was investigated. These processes include chemical bath deposition (CBD), Microreactor Assisted Solution Deposition (MASD), and PhotoChemical Deposition (PCD). The growth kinetics of copper sulfide thin films by CBD was monitored using an in-situ quartz crystal microbalance for the first time. CBD growth was studied as a function of time, temperature, concentrations of reactants, and pH. The reaction activation energy was determined based on initial growth rates. The result indicates the rate limiting step of the deposition is the chemical reaction rather than mass transport. The structure, morphology, composition and optical absorption of the films were found to depend strongly on the deposition conditions. Results from the study of CBD reactions indicated the need to de-reduce the undesirable homogeneous particle formation. The MASD process was developed to achieve this objective. The continuous flow process together with the microreactor design not only improve the mixing of reactants and provide a better temporal control over the reaction which result in higher quality films and a higher deposition rate. A particle-free flux was obtained after adjusting the key process parameters (concentration of mixed reactants, solution temperature, substrate temperature, and residence time). Significantly improved copper sulfide thin film deposition with a good selectivity of heterogeneous surface reactions was achieved. PCD basically employs the UV illumination to excite the irradiated region of the substrate in a deposition solution. It has the potential to reduce the homogeneous particle formation. We investigated the growth kinetics of copper sulfide thin films by PCD under various deposition conditions (e.g. pH, substrate position, reactant concentration, deposition time, and temperature) that influence on the film properties and characteristics. Moreover a detailed mathematical model that describes the multiple chemical reactions in the deposition mechanism was also developed in this work to have a better understanding of the reaction mechanism. Reaction rate constants were successfully estimated from the experimental data based on this model. The calculated results agree well with the experimental data. This model could serve as a useful tool for the control and optimization of photochemical deposition of copper sulfide thin films. Both CBD and PCD processes suffer from severe homogeneous particle formation which has resulted in lower deposition rate. In contrast, MASD provides good selectivity towards heterogeneous surface deposition using molecular precursors at a much higher deposition rate. Thus MASD process was used to deposit copper sulfide layers on textured substrates with nice conformal coverage. Dense, crack-free CuInSe2 thin films were fabricated successfully after adding an indium precursor layer, and followed by a selenization process. This approach offers a potential low-cost route to fabricate thin absorber solar cells.

Download or read book Science Abstracts written by and published by . This book was released on 1992 with total page 1228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metals Abstracts Index written by and published by . This book was released on 1996 with total page 1634 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2540 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Veterinary Materia Medica and Therapeutics written by BiblioBazaar and published by Nabu Press. This book was released on 2011-05 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a reproduction of a book published before 1923. This book may have occasional imperfections such as missing or blurred pages, poor pictures, errant marks, etc. that were either part of the original artifact, or were introduced by the scanning process. We believe this work is culturally important, and despite the imperfections, have elected to bring it back into print as part of our continuing commitment to the preservation of printed works worldwide. We appreciate your understanding of the imperfections in the preservation process, and hope you enjoy this valuable book.

Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 1224 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book In situ ex situ Microstructural Characterization of Cuins2 Thin Films for Photovoltaic Applications written by Beatriz Barcones Campo and published by . This book was released on 2007 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication of Ionic Liquid Electrodeposited Cu Sn Zn S Se Thin Films and Method of Making written by and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A semiconductor thin-film and method for producing a semiconductor thin-films comprising a metallic salt, an ionic compound in a non-aqueous solution mixed with a solvent and processing the stacked layer in chalcogen that results in a CZTS/CZTSS thin films that may be deposited on a substrate is disclosed.