Download or read book Design Fabrication and Characterization of Beam Supported Aluminum Nitride Thin Film Bulk Acoustic Resonators written by Lori Ann Callaghan and published by . This book was released on 2005 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Micro-mechanical filters comprised of bulk acoustic resonators are being fabricated and studied as a solution to the demands for low power consumption, high functionality devices in the telecommunication industry. A novel, suspended thin Film Bulk Acoustic wave Resonator (SFBAR) has been fabricated using an aluminum nitride film sputtered directly on a 100 silicon substrate. The suspended membrane design uses thin beams to support, as well as electrically connect, the resonator. The SFBAR has been fabricated by combining both thin film processing and bulk silicon micro machining. The AlN was etched in an Inductively Coupled Plasma (ICP) chlorine etch, using titanium dioxide as the masking material. A silicon Deep Reactive Ion Etch (DRIE) was used to create an open ended air cavity with a novel circular shape. A representative resonator, designated here as sample W9HS8 resonator 10018, was characterized with a Quality Factor values at resonance and anti-resonance of 68 and 151,

Download or read book Acoustic Wave and Electromechanical Resonators written by Humberto Campanella and published by Artech House. This book was released on 2010 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: This groundbreaking book provides you with a comprehensive understanding of FBAR (thin-film bulk acoustic wave resonator), MEMS (microelectomechanical system), and NEMS (nanoelectromechanical system) resonators. For the first time anywhere, you find extensive coverage of these devices at both the technology and application levels. This practical reference offers you guidance in design, fabrication, and characterization of FBARs, MEMS and NEBS. It discusses the integration of these devices with standard CMOS (complementary-metal-oxide-semiconductor) technologies, and their application to sensing and RF systems. Moreover, this one-stop resource looks at the main characteristics, differences, and limitations of FBAR, MEMS, and NEMS devices, helping you to choose the right approaches for your projects. Over 280 illustrations and more than 130 equations support key topics throughout the book.

Download or read book Multilayer Integrated Film Bulk Acoustic Resonators written by Yafei Zhang and published by Springer Science & Business Media. This book was released on 2012-08-28 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mulilayer Integrated Film Bulk Acoustic Resonators mainly introduces the theory, design, fabrication technology and application of a recently developed new type of device, multilayer integrated film bulk acoustic resonators, at the micro and nano scale involving microelectronic devices, integrated circuits, optical devices, sensors and actuators, acoustic resonators, micro-nano manufacturing, multilayer integration, device theory and design principles, etc. These devices can work at very high frequencies by using the newly developed theory, design, and fabrication technology of nano and micro devices. Readers in fields of IC, electronic devices, sensors, materials, and films etc. will benefit from this book by learning the detailed fundamentals and potential applications of these advanced devices. Prof. Yafei Zhang is the director of the Ministry of Education’s Key Laboratory for Thin Films and Microfabrication Technology, PRC; Dr. Da Chen was a PhD student in Prof. Yafei Zhang’s research group.

Download or read book Aluminum Nitride Thin Films Deposition for Fabrication Characterization and Fabrication of Surface Acoustic Wave Devices written by Charlee Fansler and published by . This book was released on 2008 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aluminum Nitride (AlN) thin films can be used for many device applications; for example, Surface Acoustic Wave (SAW) devices, microelectromechanical systems (MEMS) applications, and packaging applications. In this work, AlN is the critical layer in the fabrication process. One challenge is reliable deposition over wafer size substrates. The method of interest for deposition is pulsed DC sputtering. The (002) plane is the desired plane for its piezoelectric properties. The surface roughness of the deposited AlN is low and adheres well to the substrate. An AlN layer was deposited on a UNCD/Si substrate. Al was deposited on the AlN layer to form the IDTs (interdigital transducers) for SAW devices. SAW devices were fabricated on quartz - ST substrate. To verify the SAW devices work, they were tested using a network analyzer. This book discusses these results and parameters for AlN film deposition, film properties and implications for devices. This book would be beneficial for professionals, scientists, engineers, and graduate students in science and engineering working in the areas of wide bandgap semi-conductors, nitrides and piezoelectric materials and various acoustic wave devices.

Download or read book MEMS Aluminum Nitride Technology for Inertial Sensors written by Gabriele Vigevani and published by . This book was released on 2011 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design and fabrication of MEMS Inertial Sensors (both accelerometers and gyroscopes) made of Aluminum Nitride (AlN) is described in this dissertation. The goal of this work is to design and fabricate inertial sensors based on c-axis oriented AlN polycrystalline thin films. AlN is a post-CMOS compatible piezoelectric material widely used for acoustic resonators, such Bulk Acoustic Wave (BAW) and Lamb Wave Resonators (LWR). In this work we develop the design techniques necessary to obtain inertial sensors with AlN thin film technology. Being able to use AlN as structural material for both acoustic wave resonator and sensing elements is key to achieve the three level integration of RF-MEMS components, sensing elements and CMOS in the same chip. Using AlN as integration platform is particularly suitable for large consumer emerging markets where production costs are the major factor that determine a product success. In order to achieve a platform integration, the first part of this work focuses on the fabrication process: starting from the fabrication technology used for LWR devices, this work shows that by slightly modifying some of the fabrication steps it is possible to obtain MEMS accelerometers and gyroscopes with the same structural layers used for LWR. In the second part of this work, an extensive analysis, performed with analytical and Finite Element Models (FEM), is developed for beam and ring based structures. These models are of great importance as they provide tools to understand the physics of lateral piezoelectric beam actuation and the major limitations of this technology. Based on the models developed for beam based resonators, we propose two designs for Double Ended Tuning Fork (DETF) based accelerometers. In the last part of the dissertation, we show the experimental results and the measurements performed on actual devices. As this work shows analytically and experimentally, there are some fundamental constraints that limit the ultimate sensitivity of piezoelectric sensors based on resonating beam structures. Although the limitations of the structures here considered cannot achieve tactical grade sensitivities, this research proves that it is possible to achieve performances close to those required by large consumer electronics. This work proves that AlN based platforms can be a great opportunity for future developments in IMU and in general for MEMS integrated solutions.

Download or read book Fabrication and Characterization of Aluminum Nitride Thin Films Deposited by RF Magnetron Sputtering written by William A. Carrington and published by . This book was released on 1991 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Deposition of AlN Thin Films Their Characterization and the Fabrication of Surface Acoustic Wave Devices written by Charlee Fansler and published by . This book was released on 2007 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Temperature Compensated and High Q Piezoelectric Aluminum Nitride Lamb Wave Resonators for Timing and Frequency Control Applications written by Chih-Ming Lin and published by . This book was released on 2013 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The explosive development of wireless and mobile communication systems has lead to rapid technology innovation in component performance, complementary metal-oxide semiconductor (CMOS) compatible fabrication techniques, and system improvement to satisfy requirements for faster signal processing, cost efficiency, chip miniaturization, and low power consumption. The demands for the high-performance communication systems whose fundamentals are precise timing and frequency control have driven the current research interests to develop advanced reference oscillators and radio frequency (RF) bandpass filters. In turn a promising microelectromechanical systems (MEMS) resonator technology is required to achieve the ultimate goal. That is, micromechanical vibrating resonators with high quality factor (Q) and good frequency-temperature stability at high series resonance frequency (fs) are the required fundamental components for a high-performance wireless communication system. Recently, Lamb wave mode propagating in piezoelectric thin plates has attracted great attention for designs of the electroacoustic resonators since it combines the advantages of bulk acoustic wave (BAW) and surface acoustic wave (SAW): high phase velocity and multiple frequency excitation by an interdigital transducer (IDT). More specifically, the Lamb wave resonator (LWR) based on an aluminum nitride (AlN) thin film has attracted many attentions because it can offer the high resonance frequency, small temperature-induced frequency drift, low motional resistance, and CMOS compatibility. The lowest-order symmetric (S0) Lamb wave mode propagation in the AlN thin plate is particularly preferred because it exhibits a phase velocity close to 10,000 m/s, a low dispersive phase velocity characteristic, and a moderate electromechanical coupling coefficient. However, the uncompensated AlN LWR shows a first-order temperature coefficient of frequency (TCF) of approximately -25 ppm/C. This level of the temperature stability is unsuitable for any timing application. In addition, the Q of the AlN LWR is degraded to several hundred while the IDT finger width is downscaled to a nanometer scale to raise the resonance frequency up to a few GHz. This dissertation presents comprehensive analytical and experimental results on a new class of temperature-compensated and high-Q piezoelectric AlN LWRs. The temperature compensation of the AlN LWR using the S0 Lamb wave mode is achieved by adding a layer of silicon dioxide (SiO2) with an appropriate thickness ratio to the AlN thin film, and the AlN/SiO2 LWRs can achieve a low first-order TCF at room temperature. Based on the multilayer plate composed of a 1-um-thick AlN film and a 0.83-um-thick SiO2 layer, a temperature-compensated LWR operating at a series resonance frequency of 711 MHz exhibits a zero first-order TCF and a small second-order TCF of -21.5 ppb/C^2 at its turnover temperature, 18.05 C. The temperature dependence of fractional frequency variation is less than 250 parts per million (ppm) over a wide temperature range from -55 to 125 C. In addition to the temperature compensation at room temperature, the thermal compensation of the AlN LWRs is experimentally demonstrated at high temperatures. By varying the normalized AlN and SiO2 thicknesses to the wavelength, the turnover temperature can be designed at high temperatures and the AlN LWRs are temperature-compensated at 214, 430, and 542 C, respectively. The temperature-compensated AlN/SiO2 LWRs are promising for a lot of applications including thermally stable oscillators, bandpass filters, and sensors at room temperature as well as high temperatures. The influences of the bottom electrode upon the characteristics of the LWRs utilizing the S0 Lamb wave mode in the AlN thin plate are theoretically and experimentally studied. Employment of a floating bottom electrode for the LWR reduces the static capacitance in the AlN membrane and accordingly enhances the effective coupling coefficient. The floating bottom electrode simultaneously offers a large coupling coefficient and a simple fabrication process than the grounded bottom electrode but the transduction efficiency is not sacrificed. In contrast to those with the bottom electrode, an AlN LWR with no bottom electrode shows a high Q of around 3,000 since it gets rid of the electrical loss in the metal-to-resonator interface. In addition, it exhibits better power handling capacity than those with the bottom electrode since less thermal nonlinearity induced by the self-heating exists in the resonators. In order to boost the Q, a new class of the AlN LWRs using suspended convex edges is introduced in this dissertation for the first time. The suspended convex edges can efficiently reflect the Lamb waves back towards the transducer as well as confine the mechanical energy in the resonant body. Accordingly the mechanical energy dissipation through the support tethers is significantly minimized and the Q can be markedly enhanced. More specifically, the measured frequency response of a 491.8-MHz LWR with suspended biconvex edges yields a Q of 3,280 which represents a 2.6x enhancement in Q over a 517.9-MHz LWR based on the same AlN thin plate but with the suspended flat edges. The suspended convex edges can efficiently confine mechanical energy in the LWR and reduce the energy dissipation through the support tethers without increasing the motional impedance of the resonator. In addition, the radius of curvature of the suspended convex edges and the AlN thickness normalized to the wavelength can be further optimized to simultaneously obtain high Q, low motional impedance, and large effective coupling coefficient. To further enhance the Q of the LWR, a composite plate including an AlN thin film and an epitaxial cubic silicon carbide (3C-SiC) layer is introduced to enable high-Q and high-frequency micromechanical resonators utilizing high-order Lamb wave modes. The use of the epitaxial 3C-SiC layer is attractive as SiC crystals have been theoretically proven to have an exceptionally large fs and Q product due to its low acoustic loss characteristic at microwave frequencies. In addition, AlN and 3C-SiC have well-matched mechanical and electrical properties, making them a suitable material stack for the electroacoustic resonators. The epitaxial 3C-SiC layer not only provides the micromechanical resonators with a low acoustic loss layer to boost their Q but also enhances the electromechanical coupling coefficients of some high-order Lamb waves in the AlN/3C-SiC composite plate. A micromachined electroacoustic resonator utilizing the third quasi-symmetric (QS3) Lamb wave mode in the AlN/3C-SiC composite plate exhibits a Q of 5,510 at 2.92 GHz, resulting in the highest fs and Q product, 1.61x10^13 Hz, among suspended piezoelectric thin film resonators to date.

Download or read book Multilayer Integrated Film Bulk Acoustic Resonators written by Yafei Zhang and published by . This book was released on 2013 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aluminum Nitride Thin Film and Composite Bulk Wave Resonators written by K. M. Lakin and published by . This book was released on 1982 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fundamental material and device properties of miniature bulk wave resonators have been investigated for fundamental mode oscillator control and filter applications in the UHF range. The properties of aluminum nitride in the composite resonator geometry and in an edge-only supported plate configuration are reported. The AlN films were grown in a DC planar magnetron sputtering system using the plasma reaction between sputtered Al from the target and N2 in the plasma. The general sputtering conditions were as follows: substrate temperature equal 200 C, atmospheric gas equal 99.999% Nitrogen, sputtering pressure: 1 x 10 to the minus third power torr, DC power equal 225 watts and deposition rate equal 1.2 micrometer/hr. The films were evaluated by SEM, x-ray diffraction, and Auger electron spectroscopy. These results showed that the sputtered AlN films have a highly oriented structure with the c-axis normal to the surface of the Si substrate.

Download or read book Analysis of the Combined Mode Resonance in Aluminum Nitride MEMS Resonators written by Eric Walther-Grant and published by . This book was released on 2015 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aluminum Nitride (AlN) contour-extensional mode resonators (CMRs) have shown great promise for use in a wide range of technologies due to their scalability and the ability to combine multiple resonant frequencies on a single chip. However, their low coupling, and hence figure of merit, is a significant downside to their use compared to other resonator designs such as film bulk acoustic wave resonators (FBARs) and surface acoustic wave resonators. Recently, researchers have discovered a theoretical new mode of resonance that would combine d31 nd d33 piezoelectric coefficients. By combining both modes, the resonator achieves notably improved kt2, without reducing the quality factor. This thesis is a thorough analysis of this new mode, looking closely at how and why it occurs, as well as the primary underlying design variables that control it. Through extensive use of finite element model (FEM) simulation, it is first proven that the new mode in fact combines d31 and d33. This thesis also examines how the coupling behavior alters the resonant frequency and how it affects, and is affected by, spurious modes. The results of this analysis show how to design improved combined mode resonators without the extensive use of time consuming FEM simulations. To achieve this goal, models are adapted from FBAR design to enable the prediction of the combined mode’s behavior. As a result, all significant underlying design variables are examined for their individual effects on this new resonance mode. When properly implemented, the combined mode effectively adds the coupling of its two underlying modes, leading to a considerable increase in kt2, allowing it to possibly surpass both FBARs and standard CMRs in figure of merit.

Download or read book 3D and Circuit Integration of MEMS written by Masayoshi Esashi and published by John Wiley & Sons. This book was released on 2021-03-16 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explore heterogeneous circuit integration and the packaging needed for practical applications of microsystems MEMS and system integration are important building blocks for the “More-Than-Moore” paradigm described in the International Technology Roadmap for Semiconductors. And, in 3D and Circuit Integration of MEMS, distinguished editor Dr. Masayoshi Esashi delivers a comprehensive and systematic exploration of the technologies for microsystem packaging and heterogeneous integration. The book focuses on the silicon MEMS that have been used extensively and the technologies surrounding system integration. You’ll learn about topics as varied as bulk micromachining, surface micromachining, CMOS-MEMS, wafer interconnection, wafer bonding, and sealing. Highly relevant for researchers involved in microsystem technologies, the book is also ideal for anyone working in the microsystems industry. It demonstrates the key technologies that will assist researchers and professionals deal with current and future application bottlenecks. Readers will also benefit from the inclusion of: A thorough introduction to enhanced bulk micromachining on MIS process, including pressure sensor fabrication and the extension of MIS process for various advanced MEMS devices An exploration of epitaxial poly Si surface micromachining, including process condition of epi-poly Si, and MEMS devices using epi-poly Si Practical discussions of Poly SiGe surface micromachining, including SiGe deposition and LP CVD polycrystalline SiGe A concise treatment of heterogeneously integrated aluminum nitride MEMS resonators and filters Perfect for materials scientists, electronics engineers, and electrical and mechanical engineers, 3D and Circuit Integration of MEMS will also earn a place in the libraries of semiconductor physicists seeking a one-stop reference for circuit integration and the practical application of microsystems.

Download or read book Micromachined Circuits and Devices written by Shiban Kishen Koul and published by Springer Nature. This book was released on 2022-02-07 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the design of different switching and resonant devices using the present state-of-the-art radio frequency (RF) micromachining (MEMS) technology. Different topologies of MEMS switches have been discussed considering optimum performances over microwave to millimeter wave frequency range. Wide varieties of micromachined switching networks starting from single-pole-double-throw (SPDT) to single-pole-fourteen-throw (SP14T) are discussed utilizing vertical and lateral actuation movements of the switch. Different transduction mechanisms of micromachined resonators are highlighted that includes capacitive, piezoelectric, and piezoresistive types. The book provides major design guidelines for the development of MEMS-based digital phase shifters, tunable filters, and antennas with extensive measurement data. Apart from the radio frequency (RF) requirements, an extensive guideline is given for the improvement of the reliability of micromachined switches and digital phase shifters where multiple switches are operating simultaneously. It takes multiple iterations and extensive characterizations to conclude with a reliable MEMS digital phase shifter, and these aspects are given one of the prime attentions in this book. Detailed performance analysis of metamaterial inspired MEMS switches is then discussed for application in millimeter wave frequency bands up to about 170 GHz. The book concludes with future research activities of RF MEMS technology and its potential in space, defense, sensors, and biomedical applications.

Download or read book Capacitive Silicon Resonators written by Nguyen Van Toan and published by CRC Press. This book was released on 2019-07-10 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microfabricated resonators play an essential role in a variety of applications, including mass sensing, timing reference applications, and filtering applications. Many transduction mechanisms including piezoelectric, piezoresistive, and capacitive mechanisms, have been studied to induce and detect the motion of resonators. This book is meant to introduce and suggest several technological approaches together with design considerations for performance enhancement of capacitive silicon resonators, and will be useful for those working in field of micro and nanotechnology. Features Introduces and suggests several technological approaches together with design considerations for performance enhancement of capacitive silicon resonators Provides information on the various fabrication technologies and design considerations that can be employed to improve the performance capacitive silicon resonator which is one of the promising options to replace the quartz crystal resonator. Discusses several technological approaches including hermetic packaging based on the LTCC substrate, deep reactive ion etching, neutral beam etching technology, and metal-assisted chemical etching, as well as design considerations for mechanically coupled, selective vibration of high-order mode, movable electrode structures, and piezoresistive heat engines were investigated to achieve small motional resistance, low insertion loss, and high quality factor. Focusses on a capacitive sensing method based on the measurement of the change in capacitance between a sensing electrode and the resonant body. Reviews recent progress in performance enhancement methods for capacitive silicon resonator, which are mainly based on the works of the authors.

Download or read book Piezoelectric MEMS Resonators written by Harmeet Bhugra and published by Springer. This book was released on 2017-01-09 with total page 423 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces piezoelectric microelectromechanical (pMEMS) resonators to a broad audience by reviewing design techniques including use of finite element modeling, testing and qualification of resonators, and fabrication and large scale manufacturing techniques to help inspire future research and entrepreneurial activities in pMEMS. The authors discuss the most exciting developments in the area of materials and devices for the making of piezoelectric MEMS resonators, and offer direct examples of the technical challenges that need to be overcome in order to commercialize these types of devices. Some of the topics covered include: Widely-used piezoelectric materials, as well as materials in which there is emerging interest Principle of operation and design approaches for the making of flexural, contour-mode, thickness-mode, and shear-mode piezoelectric resonators, and examples of practical implementation of these devices Large scale manufacturing approaches, with a focus on the practical aspects associated with testing and qualification Examples of commercialization paths for piezoelectric MEMS resonators in the timing and the filter markets ...and more! The authors present industry and academic perspectives, making this book ideal for engineers, graduate students, and researchers.

Download or read book Tuneable Film Bulk Acoustic Wave Resonators written by Spartak Gevorgian and published by Springer Science & Business Media. This book was released on 2013-02-01 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: To handle many standards and ever increasing bandwidth requirements, large number of filters and switches are used in transceivers of modern wireless communications systems. It makes the cost, performance, form factor, and power consumption of these systems, including cellular phones, critical issues. At present, the fixed frequency filter banks based on Film Bulk Acoustic Resonators (FBAR) are regarded as one of the most promising technologies to address performance -form factor-cost issues. Even though the FBARs improve the overall performances the complexity of these systems remains high.a Attempts are being made to exclude some of the filters by bringing the digital signal processing (including channel selection) as close to the antennas as possible. However handling the increased interference levels is unrealistic for low-cost battery operated radios. Replacing fixed frequency filter banks by one tuneable filter is the most desired and widely considered scenario. As an example, development of the software based cognitive radios is largely hindered by the lack of adequate agile components, first of all tuneable filters. In this sense the electrically switchable and tuneable FBARs are the most promising components to address the complex cost-performance issues in agile microwave transceivers, smart wireless sensor networks etc.Tuneable Film Bulk Acoustic Wave Resonators discusses FBAR need, physics, designs, modelling, fabrication and applications. Tuning of the resonant frequency of the FBARs is considered. Switchable and tuneable FBARs based on electric field induced piezoelectric effect in paraelectric phase ferroelectrics are covered. The resonance of these resonators may be electrically switched on and off and tuned without hysteresis.The book is aimed at microwave and sensor specialists in the industry and graduate students. Readers will learn about principles of operation and possibilities of the switchable and tuneable FBARs, and will be given general guidelines for designing, fabrication and applications of these devices."

Download or read book Dissertation Abstracts International written by and published by . This book was released on 1996 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt: