Applications and Metrology at Nanometer Scale 1. Abdelkhalak El Hami

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      Preface

      The various actions taken worldwide in support of sustainable development and greenhouse gas emission control have led to increasingly restrictive regulations. Manufacturers in the automotive field have thus developed innovative mechatronic systems, enabling various vehicle functions to go electric. Confronted with the globalization of exchanges that has generated stronger competition and a surge of new product performances, companies in the sector of embedded mechatronic systems are developing new products at an increasingly faster rate.

      In other domains, to achieve volume or mass reduction or curb energy dissipation, manufacturers of mechatronic systems are developing new assembly methods based on multimaterials (e.g. composite materials, hybrids) or on innovative nanomaterials (e.g. carbon nanotubes). Modeling is essential to reduce product development cost, shrink time to market, understand failure mechanisms occurring in the operating conditions and optimize design before launching production. The reliability-based design optimization (RBDO) method is a modeling approach that optimizes design, guarantees the required high level of performance and takes into account the variability in the manufacturing process as well as the climatic variability in the use conditions. The efficiency of RBDO, however, depends on a solid understanding of the failure mechanisms caused by aging.

Creating a model of a dynamic system often involves developing a simplified model of its behavior based on realistic hypotheses and on the key parameters that are required for its functioning. The dynamic behavior of this modeled system is ruled by partial differential equations (PDEs). The model is then improved by introducing elements or parameters that were not initially included and by improving the set of PDEs (nonlinearity, coupling, etc.), in order to obtain a model that closely represents the reality of operating systems and provides pertinent simulation results.

      The theoretical models that are based on the fundamental laws of physics use a bottom-up approach. These models can be studied using analytical or numerical methods. When experiments can be implemented, simulation results are compared to experimental results. It is also possible to use experimental methods and a top-down approach to build a database of the response of the system to applied stresses. These data are then analyzed by comparing them to the response of theoretical or empirical models. In all the cases, there is a degree of uncertainty in the statistical analysis of the data, which leads to predictions with a margin of error. The lower the margin of error, the closer the predictions are to reality, leading to a sound understanding of the functionalities of working materials.

      As Book 9 of the “Reliability of Multiphysical Systems Set”, this book is designed to provide applications for Book 2 in the set, entitled Nanometer-scale Defect Detection Using Polarized Light. This is achieved by describing the experimental and theoretical methods developed in fundamental research laboratories to understand the physics or chemical processes, which at the nanometer scale are at the origin of the remarkable properties of the materials introduced in innovative technological devices. It presents optical techniques based on polarized light, which are used to characterize interface and bulk material defects that have an impact on the performance of nanodevices. It also describes how mechanical properties of nanomaterials can be determined using theoretical models and by the analysis of experimental results and their uncertainties.

      This book is intended for students at master and doctoral levels, teaching academics and researchers in materials science, physics engineering and experimental study, as well as R&D and manufacturing engineers of large groups and SMEs in the field of electronics, mechatronics, or optical or electronic materials.

Chapter 1 provides a historical overview of the development of nanosciences and nanotechnologies and describes the challenges encountered when working on the nanometric scale, such as finding new ways to measure the physical properties of nanomaterials. It provides an overview of the techniques used for manufacturing СКАЧАТЬ