Author: Jessica Torres
Publisher:
ISBN:
Category : Amorphous substances
Languages : en
Pages : 264
Get Book Here
Book Description
This dissertation provides a fundamental understanding of the impact of bulk polymer properties on the nanometer length scale modulus. The elastic modulus of amorphous organic thin films is examined using a surface wrinkling technique. Potential correlations between thin film behavior and intrinsic properties such as flexibility and chain length are explored. Thermal properties, glass transition temperature (Tg) and the coefficient of thermal expansion, are examined along with the moduli of these thin films. It is found that the nanometer length scale behavior of flexible polymers correlates to its bulk Tg and not the polymers intrinsic size. It is also found that decreases in the modulus of ultrathin flexible films is not correlated with the observed Tg decrease in films of the same thickness. Techniques to circumvent reductions from bulk modulus were also demonstrated. However, as chain flexibility is reduced the modulus becomes thickness independent down to 10 nm. Similarly for this series minor reductions in Tg were obtained. To further understand the impact of the intrinsic size and processing conditions; this wrinkling instability was also utilized to determine the modulus of small organic electronic materials at various deposition conditions. Lastly, this wrinkling instability is exploited for development of poly furfuryl alcohol wrinkles. A two-step wrinkling process is developed via an acid catalyzed polymerization of a drop cast solution of furfuryl alcohol and photo acid generator. The ability to control the surface topology and tune the wrinkle wavelength with processing parameters such as substrate temperature and photo acid generator concentration is also demonstrated. Well-ordered linear, circular, and curvilinear patterns are also obtained by selective ultraviolet exposure and polymerization of the furfuryl alcohol film. As a carbon precursor a thorough understanding of this wrinkling instability can have applications in a wide variety of technologies.
Author: Bruce Edward White
Publisher:
ISBN:
Category :
Languages : en
Pages : 310
Get Book Here
Book Description
Author: Mark Stephen Oliver
Publisher: Stanford University
ISBN:
Category :
Languages : en
Pages : 170
Get Book Here
Book Description
Hybrid organic-inorganic glasses are materials wherein organic and inorganic chemical components are intermixed and covalently bound at the molecular scale. This class of materials has great potential to enable and enhance a range of new technologies given their unique properties. To date, hybrid glasses have been used in a diverse range of applications including protective coatings, adhesion promoting films, ultra-low-k dielectrics, and optical waveguides. The successful integration of hybrid glasses requires that they possess sufficient mechanical properties to withstand often harsh processing and operating conditions. This dissertation presents results from several investigations of how molecular structure controls elastic and fracture properties of hybrid glasses. Two major sol-gel derived hybrid glass systems are discussed. The first is oxycarbosilane (OCS) glasses processed from small organosilane precursors. The second system is ZrOx/epoxysilane hybrids. For the OCS glasses, the primary focus of this work was to develop the capability to generate accurate molecular models of these materials and to simulate their mechanical properties using molecular dynamics as well as a novel fracture model that uses the mathematics of graph theory to predict the 3-D cohesive fracture path at the atomic scale. Using these computational tools, the impact of network connectivity on elastic stiffness and cohesive fracture energy has been elucidated. Also, the exceptionally high stiffness of OCS materials processed from 1,3,5-benzene precursors predicted by computational modeling is discussed. For the ZrOx/epoxysilane materials, linear elastic fracture mechanics experiments were done to characterize the fracture resistance of these glasses under monotonic, static, and cyclic loading conditions. The effects of glass composition, substrate composition, and silane crosslinking on the critical fracture energy were investigated. Additionally, plasticity-driven cyclic mechanical fatigue was observed, providing the first evidence of the importance of fatigue phenomena to hybrid glasses.
Author: Ophelia Kwan Chui Tsui
Publisher: World Scientific
ISBN: 9812818812
Category : Science
Languages : en
Pages : 312
Get Book Here
Book Description
Polymer thin films is an emerging area driven by their enormous technological potential and the intellectually challenging academic problems associated with them. This book contains a collection of review articles on the current topics of polymer films written by leading experts in the field. To reflect the interdisciplinary nature of this field, the contributors hail from a wide range of disciplines, including chemists, chemical engineers, materials scientists, engineers, and physicists. The goal of this book is to provide readers, whether involved in or outside of the field of polymer films, with an encompassing and informative reference.
Author: Connie B. Roth
Publisher: CRC Press
ISBN: 1315305143
Category : Science
Languages : en
Pages : 573
Get Book Here
Book Description
"the present book will be of great value for both newcomers to the field and mature active researchers by serving as a coherent and timely introduction to some of the modern approaches, ideas, results, emerging understanding, and many open questions in this fascinating field of polymer glasses, supercooled liquids, and thin films" –Kenneth S. Schweizer, Morris Professor of Materials Science & Engineering, University of Illinois at Urbana-Champaign (from the Foreword) This book provides a timely and comprehensive overview of molecular level insights into polymer glasses in confined geometries and under deformation. Polymer glasses have become ubiquitous to our daily life, from the polycarbonate eyeglass lenses on the end of our nose to large acrylic glass panes holding water in aquarium tanks, with advantages over glass in that they are lightweight and easy to manufacture, while remaining transparent and rigid. The contents include an introduction to the field, as well as state of the art investigations. Chapters delve into studies of commonalities across different types of glass formers (polymers, small molecules, colloids, and granular materials), which have enabled microscopic and molecular level frameworks to be developed. The authors show how glass formers are modeled across different systems, thereby leading to treatments for polymer glasses with first-principle based approaches and molecular level detail. Readers across disciplines will benefit from this topical overview summarizing the key areas of polymer glasses, alongside an introduction to the main principles and approaches.
Author: Carolin Hostert
Publisher:
ISBN: 9783844012149
Category :
Languages : en
Pages : 71
Get Book Here
Book Description
Author: Materials Research Society. Meeting
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 544
Get Book Here
Book Description
The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners.
Author: Jianguo Zhu
Publisher: World Scientific
ISBN: 9811224005
Category : Science
Languages : en
Pages : 706
Get Book Here
Book Description
Thin films have an extremely broad range of applications from electronics and optics to new materials and devices. Collaborative and multidisciplinary efforts from physicists, materials scientists, engineers and others have established and advanced a field with key pillars constituting (i) the synthesis and processing of thin films, (ii) the understanding of physical properties in relation to the nanometer scale, (iii) the design and fabrication of nano-devices or devices with thin film materials as building blocks, and (iv) the design and construction of novel tools for characterization of thin films.Against the backdrop of the increasingly interdisciplinary field, this book sets off to inform the basics of thin film physics and thin film devices. Readers are systematically introduced to the synthesis, processing and application of thin films; they will also study the formation of thin films, their structure and defects, and their various properties — mechanical, electrical, semiconducting, magnetic, and superconducting. With a primary focus on inorganic thin film materials, the book also ventures on organic materials such as self-assembled monolayers and Langmuir-Blodgett films.This book will be effective as a teaching or reference material in the various disciplines, ranging from Materials Science and Engineering, Electronic Science and Engineering, Electronic Materials and Components, Semiconductor Physics and Devices, to Applied Physics and more. The original Chinese publication has been instrumental in this purpose across many Chinese universities and colleges.
Author: William W. Gerberich
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 576
Get Book Here
Book Description
Interest in the mechanical properties of thin films remains high throughout the world, as evidenced by the large international contingent represented in this book. With regard to stresses, techniques for sorting out residual stress and strain states are becoming more varied and sophisticated. Discussions include Raman scattering, nonlinear acoustic responses and back-scattered electron imaging microscopies, as well as the more standard wafer-bending and X-ray techniques. Spectroscopy, indenting and the burgeoning field of nanoprobe imaging for the characterization of mechanical properties of thin films are also highlighted. Topics include: mechanical properties of films and multilayers; fracture and adhesion; nanoindentation of films and surfaces; mechanical property methods and modelling; tribological properties of thin films; properties of polymer films; stress effects in thin films and interconnects; epitaxy and strain relief mechanisms, measurements.
Author: Thomas E. Buchheit
Publisher: Cambridge University Press
ISBN: 9781558998292
Category : Technology & Engineering
Languages : en
Pages : 480
Get Book Here
Book Description
This book has a long tradition of representing current topics in thin-film properties and how they are related to the performance and reliability of thin-film structures. Several emerging and well-developed technologies rely on understanding the behavior of these structures. This book provides a forum for an exchange of ideas among researchers who are interested in the mechanical behavior of thin films, broadly applied to their materials choice or methodology. The book focuses on stress-related phenomena in thin films for a wide range of materials. Of particular interest are studies that explore the frontiers of thin-film materials science with regard to materials selection or size scale. Topics include: elasticity in thin films; characterizing thin films by nanoindentation; mechanical behavior of nanostructured films; mechanical properties of thin; thin-film plasticity; thin-film plasticity; thin-film plasticity; novel testing techniques; in situ characterization techniques; adhesion and fracture of thin films; fatigue and stress in interconnect and metallization; deformation, growth and microstructure in thin films and thin-film processing.
