Download or read book Multiscale Modeling of Thin Film Deposition Processes written by Gwang-Soo Kim and published by . This book was released on 2002 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) A reactor scale model is developed based on the Galerkin finite element method. The model includes momentum transport, transient mass transport, potential distribution and detailed surface kinetic mechanisms. The experimental film thickness uniformity on the blank wafer with commercial electrochemical deposition cell is compared with the simulation result. The reactor scale model is used to investigate the various effects on the film thickness uniformity including terminal effects and mass transport effects. The analysis shows the qualitative difference between two effects and how they can be eliminated. Also, the reactor scale simulation tool is used to model the pulse plating process. Improved performance of the pulse plating over the constant current operation suggests that the relaxation period is the critical parameter that determines the film thickness uniformity. A computationally efficient feature scale model is developed. Mass transport, potential distribution and detailed surface reactions are included in the model ...
Download or read book Chemical Physics of Thin Film Deposition Processes for Micro and Nano Technologies written by Y. Pauleau and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: An up-to-date collection of tutorial papers on the latest advances in the deposition and growth of thin films for micro and nano technologies. The emphasis is on fundamental aspects, principles and applications of deposition techniques used for the fabrication of micro and nano devices. The deposition of thin films is described, emphasising the gas phase and surface chemistry and its effects on the growth rates and properties of films. Gas-phase phenomena, surface chemistry, growth mechanisms and the modelling of deposition processes are thoroughly described and discussed to provide a clear understanding of the growth of thin films and microstructures via thermally activated, laser induced, photon assisted, ion beam assisted, and plasma enhanced vapour deposition processes. A handbook for engineers and scientists and an introduction for students of microelectronics.
Download or read book Dispersive Transport Equations and Multiscale Models written by Ben Abdallah Naoufel and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt: IMA Volumes 135: Transport in Transition Regimes and 136: Dispersive Transport Equations and Multiscale Models focus on the modeling of processes for which transport is one of the most complicated components. This includes processes that involve a wdie range of length scales over different spatio-temporal regions of the problem, ranging from the order of mean-free paths to many times this scale. Consequently, effective modeling techniques require different transport models in each region. The first issue is that of finding efficient simulations techniques, since a fully resolved kinetic simulation is often impractical. One therefore develops homogenization, stochastic, or moment based subgrid models. Another issue is to quantify the discrepancy between macroscopic models and the underlying kinetic description, especially when dispersive effects become macroscopic, for example due to quantum effects in semiconductors and superfluids. These two volumes address these questions in relation to a wide variety of application areas, such as semiconductors, plasmas, fluids, chemically reactive gases, etc.
Download or read book Uncertainty Analysis and Control of Multiscale Process Systems written by Shabnam Rasoulian and published by . This book was released on 2015 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microelectronic market imposes tight requirements upon thin film properties, including specific growth rate, surface roughness and thickness of the film. In the thin film deposition process, the microscopic events determine the configuration of the thin film surface while manipulating variables at the macroscopic level, such as bulk precursor mole fraction and substrate temperature, are essential to product quality. Despite the extensive body of research on control and optimization in this process, there is still a significant discrepancy between the expected performance and the actual yield that can be accomplished employing existing methodologies. This gap is mainly related to the complexities associated with the multiscale nature of the thin film deposition process, lack of practical online in-situ sensors at the fine-scale level, and uncertainties in the mechanisms and parameters of the system. The main goal of this research is developing robust control and optimization strategies for this process while uncertainty analysis is performed using power series expansion (PSE). The deposition process is a batch process where the measurements are available at the end of the batch; accordingly, optimization and control approaches that do not need to access online fine-scale measurements are required. In this research, offline optimization is performed to obtain the optimal temperature profile that results in specific product quality characteristics in the presence of model-plant mismatch. To provide a computationally tractable optimization, the sensitivities in PSEs are numerically evaluated using reduced-order lattices in the KMC models. A comparison between bounded and distributional parametric uncertainties has illustrated that inaccurate assumption for uncertainty description can lead to economic losses in the process. To accelerate the sensitivity analysis of the process, an algorithm has been presented to determine the upper and lower bounds on the outputs through distributions of the microscopic events. In this approach, the sensitivities in the series expansions of events are analytically evaluated. Current multiscale models are not available in closed-form and are computationally prohibitive for online applications. Thus, closed-form models have been developed in this research to predict the control objectives efficiently for online control applications in the presence of model-plant mismatch. The robust performance is quantified by estimates of the distributions of the controlled variables employing PSEs. Since these models can efficiently predict the controlled outputs, they can either be used as an estimator for feedback control purposes in the lack of sensors, or as a basis to design a nonlinear model predictive control (NMPC) framework. Although the recently introduced optical in-situ sensors have motivated the development of feedback control in the thin film deposition process, their application is still limited in practice. Thus, a multivariable robust estimator has been developed to estimate the surface roughness and growth rate based on the substrate temperature and bulk precursor mole fraction. To ensure that the control objective is met in the presence of model-plant mismatch, the robust estimator is designed such that it predicts the upper bound on the process output. The estimator is coupled with traditional feedback controllers to provide a robust feedback control in the lack of online measurements. In addition, a robust NMPC application for the thin film deposition process was developed. The NMPC makes use of closed-from models, which has been identified offline to predict the controlled outputs at a predefined specific probability. The shrinking horizon NMPC minimizes the final roughness, while satisfying the constraints on the control actions and film thickness at the end of the deposition process. Since the identification is performed for a fixed confidence level, hard constraints are defined for thin film properties. To improve the robust performance of NMPC using soft constraints, a closed-form model has been developed to estimate the first and second- order statistical moments of the thin film properties under uncertainty in the multiscale model parameters. Employing this model, the surface roughness and film thickness can be estimated at a desired probability limit during the deposition. Thus, an NMPC framework is devised that successfully minimizes the surface roughness at the end of the batch, while the film thickness meets a minimum specification at a desired probability. Therefore, the methods developed in this research enable accurate online control of the key properties of a multiscale system in the presence of model-plant mismatch.
Download or read book IUTAM Symposium on Multiscale Modeling and Characterization of Elastic Inelastic Behavior of Engineering Materials written by S. Ahzi and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: The papers in this proceeding are a collection of the works presented at the IUTAM symposium-Marrakech 2002 (October 20-25) which brought together scientists from various countries. These papers cover contemporary topics in multiscale modeling and characterization of materials behavior of engineering materials. They were selected to focus on topics related to deformation and failure in metals, alloys, intermetallics and polymers including: experimental techniques, deformation and failure mechanisms, dislocation-based modelling, microscopic-macroscopic averaging schemes, application to forming processes and to phase transformation, localization and failure phenomena, and computational advances. Key areas that are covered by some of the papers include modeling of material deformation at various scales. At the atomistic scale, results from MD simulations pertaining to deformation mechanisms in nano-crystalline materials as well as dislocation-defect interactions are presented. Advances in modeling of deformation in metals using discrete dislocation analyses are also presented, providing an insight into this emerging scientific technique that can be used to model deformation at the microscale. These papers address current engineering problems, including deformation of thin fIlms, dislocation behavior and strength during nanoindentation, strength in metal matrix composites, dislocation-crack interaction, development of textures in polycrystals, and problems involving twining and shape memory behavior. On Behalf of the organizing committee, I would like to thank Professor P.
Download or read book Control and Optimization of Multiscale Process Systems written by Panagiotis D. Christofides and published by Springer Science & Business Media. This book was released on 2008-10-28 with total page 247 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book—the first of its kind—presents general methods for feedback controller synthesis and optimization of multiscale systems, illustrating their application to thin-film growth, sputtering processes, and catalytic systems of industrial interest. The authors demonstrate the advantages of the methods presented for control and optimization through extensive simulations. Included in the work are new techniques for feedback controller design and optimization of multiscale process systems that are not included in other books. The book also contains a rich collection of new research topics and references to significant recent work.
Download or read book 13th International Symposium on Process Systems Engineering PSE 2018 July 1 5 2018 written by Mario R. Eden and published by Elsevier. This book was released on 2018-07-19 with total page 2620 pages. Available in PDF, EPUB and Kindle. Book excerpt: Process Systems Engineering brings together the international community of researchers and engineers interested in computing-based methods in process engineering. This conference highlights the contributions of the PSE community towards the sustainability of modern society and is based on the 13th International Symposium on Process Systems Engineering PSE 2018 event held San Diego, CA, July 1-5 2018. The book contains contributions from academia and industry, establishing the core products of PSE, defining the new and changing scope of our results, and future challenges. Plenary and keynote lectures discuss real-world challenges (globalization, energy, environment and health) and contribute to discussions on the widening scope of PSE versus the consolidation of the core topics of PSE. Highlights how the Process Systems Engineering community contributes to the sustainability of modern society Establishes the core products of Process Systems Engineering Defines the future challenges of Process Systems Engineering
Download or read book Evolution of Thin Film Morphology written by Matthew Pelliccione and published by Springer Science & Business Media. This book was released on 2008-01-29 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of this book is on modeling and simulations used in research on the morphological evolution during film growth. The authors emphasize the detailed mathematical formulation of the problem. The book will enable readers themselves to set up a computational program to investigate specific topics of interest in thin film deposition. It will benefit those working in any discipline that requires an understanding of thin film growth processes.
Download or read book Multiscale Computational Fluid Dynamics Modeling Parallelization and Application to Design and Control of Plasma Enhanced Chemical Vapor Deposition of Thin Film Solar Cells written by Marquis Grant Crose and published by . This book was released on 2018 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: Today, plasma-enhanced chemical vapor deposition (PECVD) remains the dominant processing method for the manufacture of silicon thin films due to inexpensive production and low operating temperatures. Nonetheless, thickness non-uniformity continues to prevent the deposition of high quality thin film layers across large wafer substrates; thickness deviations up to 20% are typical for 200 mm and above wafers. Regardless of industry, be it solar cell production or microelectronic devices, the demand for densely packed die with high quality creates a need for improved modeling and operational strategies. Over the past two decades, a number of research groups have built microscopic models for thin film growth, as well as macroscopic reactor models to approximate the gas phase reaction and transport phenomena present within PECVD systems. Unfortunately, many of the proposed modeling and simulation techniques have been overly simplified in order to reduce computational demands, or fail to capture both the macro- and microscopic domains simultaneously. In order to address persistent issues related to thickness non-uniformity in silicon processing, advanced multiscale models are needed. Motivated by these considerations, novel reactor modeling and operational control strategies are developed in this dissertation. Specifically, a macroscopic reactor scale model is presented which captures the creation of a radio frequency (RF) plasma, transport throughout the reactor domain, and thirty-four dominant plasma-phase reactions. In Chapters 2 and 3, the gas-phase dynamics are approximated using a first principles-based model, whereas the latter half of this dissertation relies on a computational fluid dynamics approach. At the microscopic scale, the complex particle interactions that define the growth of a-Si:H thin film layers are tracked using a hybrid kinetic Monte Carlo algorithm. These scales are linked via a dynamic boundary condition which is updated at the completion of each time step. A computationally efficient parallel programming scheme allows for significantly shortened computational times and solutions to previously infeasible system sizes. Transient batch deposition cycles using the aforementioned multiscale model provide new insight into the operation of PECVD systems; spatial non-uniformity in the concentration of SiH3 and H above the substrate surface is recognized as the primary mechanism responsible for non-uniform thin film product thicknesses. Two key modes are identified to address the aforementioned non-uniformity: (1) run-to-run control of the wafer substrate temperature through the adaptation of an exponentially-weighted moving average algorithm, and (2) the design of new CVD geometries which minimize spatial variations in the concentration of deposition species. These efforts have resulted in optimized PECVD showerhead designs and spatial temperature profiles which limit the thin film thickness non-uniformity to within 1% of the product specification.
Download or read book Model Reduction and Coarse Graining Approaches for Multiscale Phenomena written by Alexander N. Gorban and published by Springer Science & Business Media. This book was released on 2006-09-22 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt: Model reduction and coarse-graining are important in many areas of science and engineering. How does a system with many degrees of freedom become one with fewer? How can a reversible micro-description be adapted to the dissipative macroscopic model? These crucial questions, as well as many other related problems, are discussed in this book. All contributions are by experts whose specialities span a wide range of fields within science and engineering.
Download or read book Machine Learning Based Modelling in Atomic Layer Deposition Processes written by Oluwatobi Adeleke and published by CRC Press. This book was released on 2023-12-15 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: While thin film technology has benefited greatly from artificial intelligence (AI) and machine learning (ML) techniques, there is still much to be learned from a full-scale exploration of these technologies in atomic layer deposition (ALD). This book provides in-depth information regarding the application of ML-based modeling techniques in thin film technology as a standalone approach and integrated with the classical simulation and modeling methods. It is the first of its kind to present detailed information regarding approaches in ML-based modeling, optimization, and prediction of the behaviors and characteristics of ALD for improved process quality control and discovery of new materials. As such, this book fills significant knowledge gaps in the existing resources as it provides extensive information on ML and its applications in film thin technology. Offers an in-depth overview of the fundamentals of thin film technology, state-of-the-art computational simulation approaches in ALD, ML techniques, algorithms, applications, and challenges. Establishes the need for and significance of ML applications in ALD while introducing integration approaches for ML techniques with computation simulation approaches. Explores the application of key techniques in ML, such as predictive analysis, classification techniques, feature engineering, image processing capability, and microstructural analysis of deep learning algorithms and generative model benefits in ALD. Helps readers gain a holistic understanding of the exciting applications of ML-based solutions to ALD problems and apply them to real-world issues. Aimed at materials scientists and engineers, this book fills significant knowledge gaps in existing resources as it provides extensive information on ML and its applications in film thin technology. It also opens space for future intensive research and intriguing opportunities for ML-enhanced ALD processes, which scale from academic to industrial applications. . .
Download or read book Multiscale Modeling in Epitaxial Growth written by Axel Voigt and published by Springer Science & Business Media. This book was released on 2006-03-30 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Epitaxy is relevant for thin film growth and is a very active area of theoretical research since several years. Recently powerful numerical techniques have been used to link atomistic effects at the film's surface to its macroscopic morphology. This book also serves as an introduction into this highly active interdisciplinary field of research for applied mathematicians, theoretical physicists and computational materials scientists.
Download or read book Process Systems Engineering 2003 written by Bingzhen Chen and published by Elsevier. This book was released on 2003-06-06 with total page 801 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contains proceedings from the 8th International Symposium on Process Systems Engineering (PSE), which brought together the global community of process systems engineering researchers and practitioners involved in the creation and application of computing based methodologies for planning, design, operation, control, and maintenance of chemical processes. Contains proceeding from the 8th International Symposium on Process Systems EngineeringConference theme for PSE 2003 is 'supporting business decision making'
Download or read book Chemical Vapour Deposition CVD written by Kwang-Leong Choy and published by CRC Press. This book was released on 2019-06-07 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a timely and complete overview on chemical vapour deposition (CVD) and its variants for the processing of nanoparticles, nanowires, nanotubes, nanocomposite coatings, thin and thick films, and composites. Chapters discuss key aspects, from processing, material structure and properties to practical use, cost considerations, versatility, and sustainability. The author presents a comprehensive overview of CVD and its potential in producing high performance, cost-effective nanomaterials and thin and thick films. Features Provides an up-to-date introduction to CVD technology for the fabrication of nanomaterials, nanostructured films, and composite coatings Discusses processing, structure, functionalization, properties, and use in clean energy, engineering, and biomedical grand challenges Covers thin and thick films and composites Compares CVD with other processing techniques in terms of structure/properties, cost, versatility, and sustainability Kwang-Leong Choy is the Director of the UCL Centre for Materials Discovery and Professor of Materials Discovery in the Institute for Materials Discovery at the University College London. She earned her D.Phil. from the University of Oxford, and is the recipient of numerous honors including the Hetherington Prize, Oxford Metallurgical Society Award, and Grunfeld Medal and Prize from the Institute of Materials (UK). She is an elected fellow of the Institute of Materials, Minerals and Mining, and the Royal Society of Chemistry.
Download or read book Thin Film Processes II written by John L. Vossen and published by Gulf Professional Publishing. This book was released on 1991 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt: This sequel to an earlier work offers an exposition of important thin film deposition and etching processes. It is intended to be of use to both the beginner in any particular process and to the experienced user wishing a wider perspective. Information is presented in a tutorial format. New topics which have arisen since the first book are included and some topics from the first book are updated. The practical applications of major thin film deposition and etching processes are given special emphasis.
Download or read book Multiscale Computational Fluid Dynamics Modeling of Thermal and Plasma Atomic Layer Deposition written by Yichi Zhang and published by . This book was released on 2021 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: Facilitated by the increasing importance and demand of semiconductors for the smartphoneand even the automobile industry, thermal atomic layer deposition (ALD) has gained tremendous industrial interest as it offers a way to efficiently deposit thin-films with ultra-high conformity. It is chosen largely due to its superior ability to deliver ultra-conformal dielectric thin-films with high aspect-ratio surface structures, which are encountered more and more often in the novel design of metal-oxide-semiconductor field-effect transistors (MOSFETs) in the NAND (Not-And)-type flash memory devices. Based on the traditional thermal ALD method, the plasma enhanced atomic layer deposition (PEALD) allows for lower operating temperature and speeds up the deposition process with the involvement of plasma species. Despite the popularity of these two methods, the development of their operation policies remains a complicated and expensive task, which motivates the construction of an accurate and comprehensive simulation model. A series of studies have been carried out to elucidate the mechanisms and the conceptof the PEALD process. In particular, process characterization focuses on the development of a first-principles-based three-dimensional, multiscale computational fluid dynamics (CFD) model, together with reactor geometry optimizations, of SiO2 thinfilm thermal atomic layer deposition (ALD) using bis(tertiary-butylamino)silane (BTBAS) and ozone as precursors. Also, a comprehensive multiscale computational fluid dynamics (CFD) model incorporating the plasma generation chamber is used in the deposition of HfO2 thin-films utilizing tetrakis(dimethylamido) hafnium (TDMAHf) and O2 plasma as precursors. Despite the great deal of research effort, ALD and PEALD processes have not been fullycharacterized from the view point of process control. This study aims to use previously developed multiscale CFD simulation model to design and evaluate an optimized control scheme to deal with industrially-relevant disturbances. Specifically, an integrated control scheme using a proportional-integral (PI) controller and a run-to-run (R2R) controller is proposed and evaluated to ensure the deposition of high-quality conformal thin-films. The ALD and PEALD processes under typical disturbances are simulated using the multiscale CFD model, and the integrated controllers are applied in the process domain. Using the controller parameters determined from the open-loop results, the developed integrated PI-R2R controller successfully mitigates the disturbances in the reactor with the combined effort of both controllers.
Download or read book Ceramics and Composites Processing Methods written by Narottam P. Bansal and published by John Wiley & Sons. This book was released on 2012-04-17 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examines the latest processing and fabrication methods There is increasing interest in the application of advanced ceramic materials in diverse areas such as transportation, energy, environmental protection and remediation, communications, health, and aerospace. This book guides readers through a broad selection of key processing techniques for ceramics and their composites, enabling them to manufacture ceramic products and components with the properties needed for various industrial applications. With chapters contributed by internationally recognized experts in the field of ceramics, the book includes traditional fabrication routes as well as new and emerging approaches in order to meet the increasing demand for more reliable ceramic materials. Ceramics and Composites Processing Methods is divided into three sections: * Densification, covering the fundamentals and practice of sintering, pulsed electric current sintering, and viscous phase silicate processing * Chemical Methods, examining colloidal methods, sol-gel, gel casting, polymer processing, chemical vapor deposition, chemical vapor infiltration, reactive melt infiltration, and combustion synthesis * Physical Methods, including directional solidification, solid free-form fabrication, microwave processing, electrophoretic deposition, and plasma spraying Each chapter focuses on a particular processing method or approach. Collectively, these chapters offer readers comprehensive, state-of-the-science information on the many approaches, techniques, and methods for the processing and fabrication of advanced ceramics and ceramic composites. With its coverage of the latest processing methods, Ceramics and Composites Processing Methods is recommended for researchers and students in ceramics, materials science, structural materials, biomedical engineering, and nanotechnology.
