Download or read book Analytical Modeling and Simulation of Capacitive Micromachined Ultrasonic Transducer written by Duy Le Nguyen and published by . This book was released on 2020 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the design characterization, modeling and microfabrication of cMUTs. Four cMUTs arrays are designed with different array geometries, membranes’ dimensions as well as number of cMUT cells in an array. cMUTs are first analytically modeled and then simulated using finite element method (FEM) analysis to compare the numerical analysis results. The analytical cMUTs modeling is characterized for spring constant, resonant frequency and pull-in voltage. COMSOL Multiphysics 4.3b is use for simulation the profound insight of cMUTs’ behavior such as: resonant frequencies, pull-in voltage, membrane’s deflection and implied spring constant. This thesis also lays out the detail fabrication process flow of cMUTs. They are promised to be fabricated using mature of semiconductor processes which include photolithography, metal deposition and selective etching. In this thesis, in order to define the cMUT’s membrane, we will use direct wafer bonding technique with both chemical and O2 plasma surface activation processes to decrease the process temperature to as low as 4000C. In this thesis, the fabrication of cMUTs is proposed at low process temperature, providing compatibility with CMOS integration.
Download or read book Computational Science and Engineering written by Arpan Deyasi and published by CRC Press. This book was released on 2016-12-19 with total page 355 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational Science and Engineering contains peer-reviewed research presented at the International Conference on Computational Science and Engineering (RCC Institute of Information Technology, Kolkata, India, 4-6 October 2016). The contributions cover a wide range of topics: - electronic devices - photonics - electromagnetics - soft computing - artificial intelligence - modern communication systems Focussing on strong theoretical and methodological approaches and applications, Computational Science and Engineering will be of interest to academia and professionals involved or interested in the above mentioned domains.
Download or read book Characterization of Multiple Moving Membrane Capacitive Micromachined Ultrasonic Transducer written by Md. Iftekharul Islam and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A newly developed multiple moving membrane capacitive micromachined ultrasonic transducer (M3-CMUT) is fabricated and characterized in this thesis. Unlike the single vibrating membrane in the conventional capacitive micromachined ultrasonic transducer (CMUT), the novel design involves two deflectable membranes suspended over a fixed bottom electrode. In the presence of bias, both of the membranes deflect simultaneously, which results in a smaller cavity compared to a CMUT. To understand the basics of a capacitive transducer, an equivalent mass-spring-capacitor model of CMUT was reported. The results of this analytical model were used to develop the finite element models (FEM) of CMUT and more complex M3-CMUT in COMSOL Multiphysics software. The electromechanical analysis of these models was conducted to observe their operating conditions. Following the modeling and analysis, several single-cell, 1-D, and 2-D arrays of these devices were fabricated using PolyMUMPs technology, a sacrificial fabrication technique for the MEMS transducers. The electrical and acoustic characterizations of the fabricated devices were performed to measure the actual transducer properties. The measured data and the model results were found to be in good agreement. It was observed from the electrical impedance measurements that a higher membrane deflection was achieved in the double membrane device. The reduction in the cavity of M3-CMUT enhanced the sensitivity of the transducer. The acoustic characterization using a pitch-catch experimental setup demonstrated that the novel M3-CMUT could be used as an ultrasonic transducer. The velocity and attenuation of the acoustic waves, when the transducer used as both the transmitter and the receiver, were found to be very close to the theoretical value.
Download or read book Interdisciplinary Research in Technology and Management written by Satyajit Chakrabarti and published by CRC Press. This book was released on 2024-05-30 with total page 822 pages. Available in PDF, EPUB and Kindle. Book excerpt: IRTM 2023 We live in an inter-connected world. In the era of Industry 5.0, technology is getting embedded more and more in the way ‘we learn, live, work and play’. This progression is accelerating at a pace never seen before. Inter disciplinary and collaborative research across disciplines within the Technology domain and Management domain, and across the Technology — Management interface is opening up exciting new possibilities for solving problems whose solutions are beyond the scope of a single discipline, domain or practice, and helping to create a brave, new world. We are living in an incredible time of change. Our effort to hold such an interdisciplinary conference, in the virtual mode, apparently resonated across the academic community, as was evident from the huge response that the first ever conference on “Interdisciplinary Research in Technology and Management”, (IRTM) held in February 2021 had received from participants across many countries. This has encouraged the organizers to hold the next edition of the conference physically in Kolkata on a larger scale in the online mode. The pandemic unleashed by Covid 19 in the last two years has shaken the socio-economic foundations of countries and societies to a point where the world cannot be the same as before the pandemic. It has re-focused the world’s attention on the priority of healthcare, and healthcare infrastructure and its innovative management. Inevitably, questions have again been raised more vehemently on what kind of a world we want to live in. Environmental concerns are being pursued with renewed vigour, The urgency of developing new, robust infrastructure relevant for the new world is gaining wider consensus. By 2030, as reports suggest, cyber – physical systems, internet of things and wearable technology will be everywhere and in everything, renewable energy will power the world, and digital entertainment will take centre stage among other developments. The third edition of the conference on “Interdisciplinary Research in Technology and Management” attempts to spotlight the above concerns. The number of tracks on which papers are invited from scholars, researchers, consultants and practitioners to share their interdisciplinary research and consultative work has been enlarged. As before, the papers will be peer reviewed and authors of the selected papers will be invited to present their papers in the IRTM conference. The presentation of papers will be interspersed with Keynote Talks by eminent experts on the theme of the conference or individual domains.
Download or read book Micromachined Ultrasonic Transducers written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microfabricated ultrasonic transducers have been generated which operate in both liquids and gases. Air coupled through transmission of aluminum was observed for the first time using a pair of 2.3 MHz transducers. The dynamic range of the transducers was 110 dB, and the received signal had an SNR of 30 dB. Air coupled through transmission of steel and glass has also been observed. A theoretical model for the transducers has been refined and agrees well with experimental results. A robust microfabrication process has been developed and was used to generate air transducers which resonate from 2 to 12 MHz, as well as immersion transducers that operate in water from 1 to 20 MHz with a 60 dB dynamic range. Optimized immersion and air transducers have been designed and a dynamic range above 110 dB is anticipated. This development effort finds applications in hydrophones, medical ultrasound, nondestructive evaluation, ranging, flow metering, and scanning tip force sensing and lithography.
Download or read book Proceedings of ICDMC 2019 written by Lung-Jieh Yang and published by Springer. This book was released on 2021-06-02 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises select proceedings of the International Conference on Design, Materials, Cryogenics and Constructions (ICDMC 2019). The chapters cover latest research in different areas of mechanical engineering such as additive manufacturing, automation in industry and agriculture, combustion and emission control, CFD, finite element analysis, and engineering design. The book also focuses on cryogenic systems and low-temperature materials for cost-effective and energy-efficient solutions to current challenges in the manufacturing sector. Given its contents, the book can be useful for students, academics, and practitioners.
Download or read book Modeling Design and Characterization of Capacitive Micromachined Ultrasonic Transducers CMUTs written by Alessandro Caronti and published by . This book was released on 2003 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation of a Capacitive Micromachined Ultrasonic Transducer with a Parylene Membrane and Graphene Electrodes written by David Sadat and published by . This book was released on 2012 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: Medical ultrasound technology accounts for over half of all imaging tests performed worldwide. In comparison to other methods, ultrasonic imaging is more portable and lower cost, and is becoming more accessible to remote regions where traditionally no medical imaging can be done. However, conventional ultrasonic imaging systems still rely on expensive PZT-based ultrasound probes that limit broader applications. In addition, the resolution of PZT based transducers is low due to the limitation in hand-fabrication methods of the piezoelectric ceramics. Capacitive Micromachined Ultrasonic Transducers (CMUTs) appears as an alternative to the piezoelectric (PZT) ceramic based transducer for ultrasound medical imaging. CMUTs show better ultrasound transducer design for batch fabrication, higher axial resolution of images, lower fabrication costs of the elements, ease of fabricating large arrays of cells using MEMS fabrication, and the extremely important potential to monolithically integrate the 2D transducer arrays directly with IC circuits for real-time 3D imaging. Currently most efforts on CMUTs are silicon based. Problems with current silicon-based CMUT designs include low pressure transmission and high-temperature fabrication processes. The pressure output from the silicon based CMUTs cells during transmission are too low when compared to commercially available PZT transducers, resulting in relatively blurry ultrasound images. The fabrication of the silicon-based cells, although easier than PZT transducers, still suffers from inevitable high temperature process and require specialized and expensive equipment. Manufacturing at an elevated temperature hinders the capability of fabricating front end analog processing IC circuits, thus it is difficult to achieve true 3D/4D imaging. Therefore novel low temperature fabrication with a low cost nature is needed. A polymer (Parylene) based CMUTs transducer has been investigated recently at UCF and aims to overcome limitations posted from the silicon based counterparts. This thesis describes the numerical simulation work and proposed fabrication steps of the Parylene based CMUT. The issue of transducer cost and pressure transmission is addressed by proposing the use of low cost and low temperature Chemical Vapor Deposition (CVD) fabrication of Parylene-C as the structural membrane plus graphene for the membrane electrodes. This study focuses mainly on comparing traditional silicon-based CMUT designs against the Parylene-C/Graphene CMUT based transducer, by using MEMS modules in COMSOL. For a fair comparison, single CMUT cells are modeled and held at a constant diameter and the similar operational frequency at the structural center. The numerical CMUT model is characterized for: collapse voltage, membrane deflection profile, center frequency, peak output pressure transmission over the membrane surface, and the sensitivity to the change in electrode surface charge. This study took the unique approaches in defining sensitivity of the CMUT by calculating the membrane response and the change in the electrode surface charge due to an incoming pressure wave. Optimal design has been achieved based on the simulation results. In comparison to silicon based CMUTs, the Parylene/Graphene based CMUT transducer produces 55% more in volume displacement and more than 35% in pressure output. The thesis has also laid out the detailed fabrication processes of the Parylene/Graphene based CMUT transducers. Parylene/Graphene based ultrasonic transducers can find wide applications in both medical imaging and Non destructive evaluation (NDE).
Download or read book Modeling and Simulation of Electromechanical Transducers in Microsystems Using an Analog Hardware Description Language written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The analytical modeling and simulation of conservative electrostatic, electromagnetic and electrodynamic transducers found in microsystems using a non-linear lumped-parameter approach is presented in this paper. A comparison is made between this approach and the linearized equivalent circuit method. All models of transducers are written in HDL-ATM, a proprietary analogue hardware description language (HDL). System-level simulation is performed in the SPICE simulator using behavioral models of the transducers. Finally, a parameter extraction and HDL model generation tool for devices is presented.
Download or read book Design and Characterization of Capacitive Micromachined Ultrasonic Transducers Using Finite Element Modeling written by Bradley John Kirchmayer and published by . This book was released on 2006 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acoustic Simulation and Characterization of Capacitive Micromachined Ultrasonic Transducers written by Markus Klemm and published by . This book was released on 2017-05-29 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling and Characterization of Nonlinear Phenomena in Circular Capacitive Micromachined Ultrasonic Transducers with Geometrical Imperfections written by Aymen Jallouli and published by . This book was released on 2018 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: Micro Electro Mechanical Systems (MEMS) have attracted the interest of scientists and engineers thanks to the variety of their applications and their significant roles in our real life. One of the most important microsystems is the capacitive micromachined ultrasonic transducer (CMUT), which is used for transmitting ultrasonic waves, for instance in medical imaging and therapy. In such applications, a high-transmitted acoustic power is needed which implies driving the CMUT in the nonlinear regime. Moreover, from a manufacturing point of view, the fabrication of a CMUT with a flat surface is extremely difficult even with the recent advances in the fabrication process. Modeling this type of microsystem while including the main sources of nonlinearities and geometric imperfections is a challenging step in understanding its static and dynamic behavior.In this thesis, a multiphysics model of imperfect CMUTs is developed taking into account the geometric and electrostatic nonlinearities. The governing equations of motions are derived from the von Kármán plate theory and spatially discretized using the Differential Quadrature Method (DQM). For the static response, numerical simulations and experimental characterizations have been conducted on flat and curved CMUTs, showing that a positive initial deflection leads to an increase in the pull-in voltage. The nonlinear dynamic behavior of a CMUT is studied by discretizing the time variable using the Finite Difference Method (FDM). The nonlinear frequency and force responses have been determined by combining FDM with the arclength continuation technique. It is shown that the CMUT can exhibit a hardening or softening behavior depending on the DC voltage. An experimental validation of the numerical model is performed for the case of flat and curved microplates. We demonstrate that the geometric imperfection modifies the nonlinear frequency response of a CMUT from hardening to softening, increases its bistability domain and permits the tuning of its bifurcation topology.The numerical model is extended to investigate the effect of an air film on the dynamic behavior of the microplate by coupling the nonlinear mechanical equations with the Reynolds equation. The complex resonance frequencies of the multi-physical problem are determined by solving the damped linear system. An experimental and numerical validation of the model is performed by determining the resonance frequencies at several static pressures. We demonstrate that the air film is able to modify the dynamic response of the CMUT by adding stiffness and damping. By decreasing the static pressure, the resonance frequency of the coupled problem decreases and becomes closer to the natural resonance frequency of the microplate. Moreover, the frequency response of the system becomes nonlinear due the decrease in the damping coefficient. At atmospheric pressure, the softening type behavior of the CMUT is obtained by applying high excitation levels. The presented numerical model is a very efficient tool to understand the nonlinear dynamic behavior CMUTs and to enhance their performances.
Download or read book Advances in Engineering Research and Application written by Kai-Uwe Sattler and published by Springer Nature. This book was released on 2020-11-23 with total page 899 pages. Available in PDF, EPUB and Kindle. Book excerpt: This proceedings book features volumes gathered selected contributions from the International Conference on Engineering Research and Applications (ICERA 2020) organized at Thai Nguyen University of Technology on December 1–2, 2020. The conference focused on the original researches in a broad range of areas, such as Mechanical Engineering, Materials and Mechanics of Materials, Mechatronics and Micromechatronics, Automotive Engineering, Electrical and Electronics Engineering, and Information and Communication Technology. Therefore, the book provides the research community with authoritative reports on developments in the most exciting areas in these fields.
Download or read book Analysis and Design Principles of MEMS Devices written by Minhang Bao and published by Elsevier. This book was released on 2005-04-12 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Mechatronics written by A. Preumont and published by Springer Science & Business Media. This book was released on 2006-09-09 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume treats Lagrange equations for electromechanical systems, including piezoelectric transducers and selected applications. It is essentially an extension to piezoelectric systems of the work by Crandall et al.:"Dynamics of Mechanical and Electromechanical Systems", published in 1968. The first three chapters contain classical material based on this and other well known standard texts in the field. Some applications are new and include material not published in a monograph before.
Download or read book Thin Plates and Shells written by Eduard Ventsel and published by CRC Press. This book was released on 2001-08-24 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presenting recent principles of thin plate and shell theories, this book emphasizes novel analytical and numerical methods for solving linear and nonlinear plate and shell dilemmas, new theories for the design and analysis of thin plate-shell structures, and real-world numerical solutions, mechanics, and plate and shell models for engineering appli
Download or read book Piezoelectric Transducers and Applications written by Antonio Arnau and published by Springer Science & Business Media. This book was released on 2004 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: Piezoelectric Transducers and Applications provides a guide for graduate students and researchers to the current state of the art of this complex and multidisciplinary area. The book fills an urgent need for a unified source of information on piezoelectric devices and their astounding variety of existing and emerging applications. Some of the chapters focus more on the basic concepts of the different disciplines involved and are presented in a didactic manner. Others go deeper into the complex aspects of specific fields of research, thus reaching the technical level of a scientific paper. Among other topics resonant sensors, especially bulk acoustic wave thickness shear mode resonators, chemical and bio-sensors, as well as broadband ultrasonic systems are treated in-depth.
