Micro Mechanical Transducers

Some years ago, silicon-based mechanical sensors, like pressure sensors, accelerometers and gyroscopes, started their successful advance. Every year, hundreds of millions of these devices are sold, mainly for medical and automotive applications. The airbag sensor on which research already started several decades ago at Stanford University can be found in every new car and has saved already numerous lives. Pressure sensors are also used in modern electronic blood pressure equipment. Many other mechanical sensors, mostly invisible to the public, perform useful functions in countless industrial and consumer products. The underlying physics and technology of silicon-based mechanical sensors is rather complex and is treated in numerous publications scattered throughout the literature. Therefore, a clear need existed for a handbook that thoroughly and systematically reviews the present basic knowledge on these devices. After a short introduction, Professor Bao discusses the main issues relevant to silicon-based mechanical sensors. First a thorough treatment of stress and strain in diaphragms and beams is presented. Next, vibration of mechanical structures is illuminated, followed by a chapter on air damping. These basic chapters are then succeeded by chapters in which capacitive and piezoresistive sensing techniques are amply discussed. The book concludes with chapters on commercially available pressure sensors, accelerometers and resonant sensors in which the above principles are applied. Everybody, involved in designing silicon-based mechanical sensors, will find a wealth of useful information in the book, assisting the designer in obtaining highly optimized devices.

Sensors and actuators are now part of our everyday life and appear in many appliances, such as cars, vending machines and washing machines. MEMS (Micro Electro Mechanical Systems) are micro systems consisting of micro mechanical sensors, actuators and micro electronic circuits. A variety of MEMS devices have been developed and many mass produced, but the information on these is widely dispersed in the literature. This book presents the analysis and design principles of MEMS devices. The information is comprehensive, focusing on microdynamics, such as the mechanics of beam and diaphragm structures, air damping and its effect on the motion of mechanical structures. Using practical examples, the author examines problems associated with analysis and design, and solutions are included at the back of the book. The ideal advanced level textbook for graduates, Analysis and Design Principles of MEMS Devices is a suitable source of reference for researchers and engineers in the field. * Presents the analysis and design principles of MEMS devices more systematically than ever before. * Includes the theories essential for the analysis and design of MEMS includes the dynamics of micro mechanical structures * A problem section is included at the end of each chapter with answers provided at the end of the book.

In ten sections this book describes the principles and technology of Micro Mechanical Systems. Section one is a general introduction to the historical background and the parallels to microelectronics, reviewing the motivation for microsystems, and discussing microphysics and design and the evolution from microcomponents to microsystems. Section two covers the areas of photolithographic microfabrication, basic concepts of planar processing, materials, and processes. Section three looks at micromachining by machine tools, its history, basic principles and preparation methods. Section four discusses tribological aspects of microsystems. Section five covers fabrication, performance and examples of silicon microsensors. Section six looks at electric and magnetic micro-actuators for micro-robots. Section seven covers energy source and power supply methods. Section eight covers controlling principles and methods of micro mechanical systems and section nine gives examples of microsystems and micromachines. The final section discusses the future problems and outlook of micro mechanical systems.

Annotation Engineers and researchers can turn to this reference time and time again when they need to overcome challenges in design, simulation, fabrication, and application of MEMS (microelectromechanical systems) sensors.

This book provides a comprehensive description of microsensors for mechanical quantities (flow, pressure, force, inertia) fabricated by silicon micromachining. Since the design of such sensors requires interdisciplinary teamwork, the presentation is made accessible to engineers trained in electrical and mechanical engineering, physics and chemistry. The reader is guided through the micromachining fabrication process. A chapter on microsensor packaging completes the discussion of technological problems. The description of the basic physics required for sensor design includes the mechanics of deformation and the piezoresistive transduction to electrical signals. There is also a comprehensive discussion of resonant sensors, the hydrodynamics and heat transfer relevant for flow sensors, and, finally, electronic interfacing and readout circuitry. Numerous up-to-date case studies are presented, together with the working, fabrication and design of the sensors.

Part I introduces the basic "Principles and Methods of Force Measurement" according to a classification into a dozen of force transducers types: resistive, inductive, capacitive, piezoelectric, electromagnetic, electrodynamic, magnetoelastic, galvanomagnetic (Hall-effect), vibrating wires, (micro)resonators, acoustic and gyroscopic. Two special chapters refer to force balance techniques and to combined methods in force measurement. Part II discusses the "(Strain Gauge) Force Transducers Components", evolving from the classical force transducer to the digital / intelligent one, with the incorporation of three subsystems (sensors, electromechanics and informatics). The elastic element (EE) is the "heart" of the force transducer and basically determines its performance. A 12-type elastic element classification is proposed (stretched / compressed column or tube, bending beam, bending and/or torsion shaft, middle bent bar with fixed ends, shear beam, bending ring, yoke or frame, diaphragm, axial-stressed torus, axisymmetrical and voluminous EE), with emphasis on the optimum location of the strain gauges. The main properties of the associated Wheatstone bridge, best suited for the parametrical transducers, are examined, together with the appropriate electronic circuits for SGFTs. The handbook fills a gap in the field of Force Measurement, both experts and newcomers, no matter of their particular interest, finding a lot of useful and valuable subjects in the area of Force Transducers; in fact, it is the first specialized monograph in this inter- and multidisciplinary field.

Microfabrication for Industrial Applications focuses on the industrial perspective for micro- and nanofabrication methods including large-scale manufacturing, transfer of concepts from lab to factory, process tolerance, yield, robustness, and cost. It gives a history of miniaturization, micro- and nanofabrication, and surveys industrial fields of application, illustrating fabrication processes of relevant micro and nano devices. Concerning sub-micron feature manufacture, the book explains: the philosophy of micro/ nanofabrication for integrated circuit industry; thin film deposition; (waveguide, plastic, semiconductor) material processing; packaging; interconnects; stress (e.g., thin film residual); economic; and environmental aspects. Micro/nanomechanical sensors and actuators are explained in depth with information on applications, materials (incl. functional polymers), methods, testing, fabrication, integration, reliability, magnetic microstructures, etc. Shows engineers & students how to evaluate the potential value of current and nearfuture manufacturing processes for miniaturized systems in industrial environments Explains the top-down and bottom up approaches to nanotechnology, nanostructures fabricated with beams, nano imprinting methods, nanoparticle manufacturing (and their health aspects), nanofeature analysis, and connecting nano to micro to macro Discusses issues for practical application cases; possibilities of dimension precision; large volume manufacturing of micro- & nanostructures (machines, materials, costs) Explains applications of Microsystems for information technology, e.g.: data recording (camera, microphone), storage (memories, CDs), communication; computing; and displays (beamers, LCD, TFT) Case studies are given for sensors, resonators, probes, transdermal medical systems, micro- pumps & valves, inkjets, DNA-analysis, lab-on-a-chip, & micro-cooling

Nano- and Microfabrication for Industrial and Biomedical Applications, Second Edition, focuses on the industrial perspective on micro- and nanofabrication methods, including large-scale manufacturing, the transfer of concepts from lab to factory, process tolerance, yield, robustness, and cost. The book gives a history of miniaturization and micro- and nanofabrication, and surveys industrial fields of application, illustrating fabrication processes of relevant micro and nano devices. In this second edition, a new focus area is nanoengineering as an important driver for the rise of novel applications by integrating bio-nanofabrication into microsystems. In addition, new material covers lithographic mould fabrication for soft-lithography, nanolithography techniques, corner lithography, advances in nanosensing, and the developing field of advanced functional materials. Luttge also explores the view that micro- and nanofabrication will be the key driver for a "tech-revolution" in biology and medical research that includes a new case study that covers the developing organ-on-chip concept. Presents an interdisciplinary approach that makes micro/nanofabrication accessible equally to engineers and those with a life science background, both in academic settings and commercial R&D Provides readers with guidelines for assessing the commercial potential of any new technology based on micro/nanofabrication, thus reducing the investment risk Updated edition presents nanoengineering as an important driver for the rise of novel applications by integrating bio-nanofabrication into microsystems