Growth and Morphological Evolution of Solid Thin Film

Growth and Morphological Evolution of Solid Thin Film PDF Author: Huifang Zhang
Publisher:
ISBN:
Category :
Languages : en
Pages : 268

Get Book Here

Book Description

Growth and Morphological Evolution of Solid Thin Film

Growth and Morphological Evolution of Solid Thin Film PDF Author: Huifang Zhang
Publisher:
ISBN:
Category :
Languages : en
Pages : 268

Get Book Here

Book Description


Evolution of Thin Film Morphology

Evolution of Thin Film Morphology PDF Author: Matthew Pelliccione
Publisher: Springer Science & Business Media
ISBN: 0387751092
Category : Technology & Engineering
Languages : en
Pages : 206

Get Book Here

Book Description
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.

Morphological Evolution and Instabilities of Solid Thin Films and Wires

Morphological Evolution and Instabilities of Solid Thin Films and Wires PDF Author: Wanxi Kan
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description


Evolution of Thin-Film and Surface Structure and Morphology: Volume 355

Evolution of Thin-Film and Surface Structure and Morphology: Volume 355 PDF Author: B. G. Demczyk
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 696

Get Book Here

Book Description
The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners.

Morphological and Compositional Evolution of Thin Films: Volume 749

Morphological and Compositional Evolution of Thin Films: Volume 749 PDF Author: Michael J. Aziz
Publisher: Mrs Proceedings
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 448

Get Book Here

Book Description
"The papers compiled in this volume were presented in Symposium W, 'Morphological and Compositional Evolution of Thin Films, ' held December 2-5 at the 2002 MRS Fall Meeting in Boston Massachusetts. They are organized in the order that they were presented."--P. xiii.

Thin metal films on weakly-interacting substrates

Thin metal films on weakly-interacting substrates PDF Author: Andreas Jamnig
Publisher: Linköping University Electronic Press
ISBN: 9179298206
Category :
Languages : en
Pages : 108

Get Book Here

Book Description
Vapor-based growth of thin metal films with controlled morphology on weakly-interacting substrates (WIS), including oxides and van der Waals materials, is essential for the fabrication of multifunctional metal contacts in a wide array of optoelectronic devices. Achieving this entails a great challenge, since weak film/substrate interactions yield a pronounced and uncontrolled 3D morphology. Moreover, the far-from-equilibrium nature of vapor-based film growth often leads to generation of mechanical stress, which may further compromise device reliability and functionality. The objectives of this thesis are related to metal film growth on WIS and seek to: (i) contribute to the understanding of atomic-scale processes that control film morphological evolution; (ii) elucidate the dynamic competition between nanoscale processes that govern film stress generation and evolution; and (iii) develop methodologies for manipulating and controlling nanoscale film morphology between 2D and 3D. Investigations focus on magnetron sputter-deposited Ag and Cu films on SiO2 and amorphous carbon (a-C) substrates. Research is conducted by strategically combining of in situ and real-time film growth monitoring, ex situ chemical and (micro)-structural analysis, optical modelling, and deterministic growth simulations. In the first part, the scaling behavior of characteristic morphological transition thicknesses (i.e., percolation and continuous film formation thickness) during growth of Ag and Cu films on a-C are established as function of deposition rate and temperature. These data are interpreted using a theoretical framework based on the droplet growth theory and the kinetic freezing model for island coalescence, from which the diffusion rates of film forming species during Ag and Cu growth are estimated. By combining experimental data with ab initio molecular dynamics simulations, diffusion of multiatomic clusters, rather than monomers, is identified as the rate-limiting structure-forming process. In the second part, the effect of minority metallic or gaseous species (Cu, N2, O2) on Ag film morphological evolution on SiO2 is studied. By employing in situ spectroscopic ellipsometry, it is found that addition of minority species at the film growth front promotes 2D morphology, but also yields an increased continuous-layer resistivity. Ex situ analyses show that 2D morphology is favored because minority species hinder the rate of coalescence completion. Hence, a novel growth manipulation strategy is compiled in which minority species are deployed with high temporal precision to selectively target specific film growth stages and achieve 2D morphology, while retaining opto-electronic properties of pure Ag films. In the third part, the evolution of stress during Ag and Cu film growth on a-C and its dependence on growth kinetics (as determined by deposition rate, substrate temperature) is systematically investigated. A general trend toward smaller compressive stress magnitudes with increasing temperature/deposition rate is found, related to increasing grain size/decreasing adatom diffusion length. Exception to this trend is found for Cu films, in which oxygen incorporation from the residual growth atmosphere at low deposition rates inhibits adatom diffusivity and decreases the magnitude of compressive stress. The effect of N2 on stress type and magnitude in Ag films is also studied. While Ag grown in N2-free atmosphere exhibits a typical compressive-tensile-compressive stress evolution as function of thickness, addition of a few percent of N2 yields to a stress turnaround from compressive to tensile stress after film continuity which is attributed to giant grain growth and film roughening. The overall results of the thesis provide the foundation to: (i) determine diffusion rates over a wide range of WIS film/substrates systems; (ii) design non-invasive strategies for multifunctional contacts in optoelectronic devices; (iii) complete important missing pieces in the fundamental understanding of stress, which can be used to expand theoretical descriptions for predicting and tuning stress magnitude. La morphologie de films minces métalliques polycristallins élaborés par condensation d’une phase vapeur sur des substrats à faible interaction (SFI) possède un caractère 3D intrinsèque. De plus, la nature hors équilibre de la croissance du film depuis une phase vapeur conduit souvent à la génération de contraintes mécaniques, ce qui peut compromettre davantage la fiabilité et la fonctionnalité des dispositifs optoélectroniques. Les objectifs de cette thèse sont liés à la croissance de films métalliques sur SFI et visent à: (i) contribuer à une meilleure compréhension des processus à l'échelle atomique qui contrôlent l'évolution morphologique des films; (ii) élucider les processus dynamiques qui régissent la génération et l'évolution des contraintes en cours de croissance; et (iii) développer des méthodologies pour manipuler et contrôler la morphologie des films à l'échelle nanométrique. L’originalité de l’approche mise en œuvre consiste à suivre la croissance des films in situ et en temps réel par couplage de plusieurs diagnostics, complété par des analyses microstructurales ex situ. Les grandeurs mesurées sont confrontées à des modèles optiques et des simulations atomistiques. La première partie est consacrée à une étude de comportement d’échelonnement des épaisseurs de transition morphologiques caractéristiques, à savoir la percolation et la continuité du film, lors de la croissance de films polycristallins d'Ag et de Cu sur carbone amorphe (a-C). Ces grandeurs sont examinées de façon systématique en fonction de la vitesse de dépôt et de la température du substrat, et interprétées dans le cadre de la théorie de la croissance de gouttelettes suivant un modèle cinétique décrivant la coalescence d’îlots, à partir duquel les coefficients de diffusion des espèces métalliques sont estimés. En confrontant les données expérimentales à des simulations par dynamique moléculaire ab initio, la diffusion de clusters multiatomiques est identifiée comme l’étape limitante le processus de croissance. Dans la seconde partie, l’incorporation, et l’impact sur la morphologie, d’espèces métalliques ou gazeuses minoritaires (Cu, N2, O2) lors de la croissance de film Ag sur SiO2 est étudié. A partir de mesures ellipsométriques in situ, on constate que l'addition d'espèces minoritaires favorise une morphologie 2D, entravant le taux d'achèvement de la coalescence, mais donne également une résistivité accrue de la couche continue. Par conséquent, une stratégie de manipulation de la croissance est proposée dans laquelle des espèces minoritaires sont déployées avec une grande précision temporelle pour cibler sélectivement des stades de croissance de film spécifiques et obtenir une morphologie 2D, tout en conservant les propriétés optoélectroniques des films d’Ag pur. Dans la troisième partie, l'évolution des contraintes résiduelles lors de la croissance des films d'Ag et de Cu sur a-C et leur dépendance à la cinétique de croissance est systématiquement étudiée. On observe une tendance générale vers des amplitudes de contrainte de compression plus faibles avec une augmentation de la température/vitesse de dépôt, liée à l'augmentation de la taille des grains/à la diminution de la longueur de diffusion des adatomes. Également, l’ajout dans le plasma de N2 sur le type et l'amplitude des contraintes dans les films d'Ag est étudié. L'ajout de quelques pourcents de N2 en phase gaz donne lieu à un renversement de la contrainte de compression et une évolution en tension au-delà de la continuité du film. Cet effet est attribué à une croissance anormale des grains géants et le développement de rugosité de surface. L’ensemble des résultats obtenus dans cette thèse fournissent les bases pour: (i) déterminer les coefficients de diffusion sur une large gamme de systèmes films/SFI; (ii) concevoir des stratégies non invasives pour les contacts multifonctionnels dans les dispositifs optoélectroniques; (iii) apporter des éléments de compréhension à l’origine du développement de contrainte, qui permettent de prédire et contrôler le niveau de contrainte intrinsèque à la croissance de films minces polycristallins.

Nanoscale structure forming processes

Nanoscale structure forming processes PDF Author: Viktor Elofsson
Publisher: Linköping University Electronic Press
ISBN: 9176856399
Category :
Languages : en
Pages : 92

Get Book Here

Book Description
Thin film growth from the vapor phase has for a long time intrigued researchers endeavouring to unravel and understand atomistic surface processes that govern film formation. Their motivation has not been purely scientific, but also driven by numerous applications where this understanding is paramount to knowledge-based design of novel film materials with tailored properties. Within the above framework, this thesis investigates growth of metal films on weakly bonding substrates, a combination of great relevance for applications concerning e.g., catalysis, graphene metallization and architectural glazing. When metal vapor condenses on weakly bonding substrates three dimensional islands nucleate, grow and coalesce prior to forming a continuous film. The combined effect of these initial growth stages on film formation and morphology evolution is studied using pulsed vapor fluxes for the model system Ag/SiO2. It is shown that the competition between island growth and coalescence completion determines structure evolution. The effect of the initial growth stages on film formation is also examined for the tilted columnar microstructure obtained when vapor arrives at an angle that deviates from the substrate surface normal. This is done using two metals with distinctly different nucleation behaviour, and the findings suggest that the column tilt angle is set by nucleation conditions in conjunction with shadowing of the vapor flux by adjacent islands. Vapor arriving at an angle can in addition result in films that exhibit preferred crystallographic orientations, both out-of-plane and in-plane. Their emergence is commonly described by an evolutionary growth model, which for some materials predict a double in-plane alignment that has not been observed experimentally. Here, an experiment is designed to replicate the model’s growth conditions, confirming the existence of double in-plane alignment. New and added film functionalities can further be unlocked by alloying. Properties are then largely set by chemistry and atomic arrangement, where the latter can be affected by thermodynamics, kinetics and vapor flux modulation. Their combined effect on atomic arrangement is here unravelled by presenting a research methodology that encompasses high resolution vapor flux modulation, nanoscale structure v vi probes and growth simulations. The methodology is deployed to study the immiscible Ag-Cu and miscible Ag-Au model systems, for which it is shown that capping of Cu by Ag atoms via near surface diffusion processes and rough morphology of the Ag-Au growth front are the decisive structure forming processes in each respective system. The results generated in this thesis are of relevance for tuning structure of metal films grown on weakly bonding substrates. They also indicate that improved growth models are required to accurately describe structure evolution and emergence of a preferred in-plane orientation in films where vapor arrives at an angle that deviates from the substrate surface normal. In addition, this thesis presents a methodology that can be used to identify and understand structure forming processes in multicomponent films, which may enable tailoring of atomic arrangement and related properties in technologically relevant material systems.

Structural and Morphological Evolution in Metal-Organic Films and Multilayers

Structural and Morphological Evolution in Metal-Organic Films and Multilayers PDF Author: Alokmay Datta
Publisher: CRC Press
ISBN: 1482232715
Category : Science
Languages : en
Pages : 219

Get Book Here

Book Description
Structural and Morphological Evolution in Metal-Organic Films and Multilayers presents major results of the authors' work carried out on Langmuir monolayers and Langmuir-Blodgett multilayers. The authors address two important questions:Are metal-organic monolayer systems more like solids or more like liquids?Does a two-dimensional system have diffe

Growth, Microstructure and Morphology Evolution of CeO2 Thin Films

Growth, Microstructure and Morphology Evolution of CeO2 Thin Films PDF Author: Sissel N. Jacobsen
Publisher:
ISBN: 9789172192416
Category :
Languages : en
Pages : 65

Get Book Here

Book Description


Morphology of Thin Film Growth

Morphology of Thin Film Growth PDF Author: R. W. Collins
Publisher:
ISBN:
Category :
Languages : en
Pages : 4

Get Book Here

Book Description
Thin films prepared by vapor deposition methods have a range of applications which demand control over the microstructural, electronic, and/or optical properties. Empirical classification schemes for the morphology of vapor-deposited thin films have been developed over the years in attempts to provide physical insights into the relationships between preparation parameters and resulting film properties. A variety of computational techniques have also been applied to model film growth and to elucidate, the physical principles that account for the observed morphological development. These include continuum, molecular dynamics, Monte Carlo, and ballistic aggregation techniques. In continuum models of film growth, many authors have studied the stability of one-dimensional surface profiles in response to sinusoidal perturbations of wavelength, lambda r. Effects of finite atomic size and shadowing by asperities have been proposed to enhance the perturbations, whereas adatom surface diffusion damps them. A smooth profile can be regained for lambda r lambda o, where lambda o is the adatom diffusion length. When lambda r lambda o, a modulated profile develops that appears analogous to experimentally-observable columnar morphology. In the experimental situation, clustering associated with initial nucleation is the dominant surface perturbation for thin film deposition on dissimilar substrates. It is technologically important to determine and control the evolution of surface morphology with subsequent film growth. Of direct importance here is the ability to fabricate multilayered structures with smooth interfaces.