The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Buckled membranes are commonly used in microelectromechanical systems (MEMS) structures. One application of a microfabricated membrane is pressure sensing. A differential pressure across the membrane causes deflection, up or down, which can be measured and related to a specific pressure change. Recent work has demonstrated that the deflection and stiffness of these membranes can be tuned through localized...
RF-MEMS filters will substitute conventional filters as they offer better performance at optimum cost. A bandpass filter is one such filter which is designed using microelectro-mechanical systems (MEMS) technology which have low insertion loss, high quality factors, good temperature stability and have various unique advantages. This paper reports on the implementation of wide bandpass filter using...
In this work, the fabrication of an acoustic sound absorbing surface (i.e. liner) made of commercial Visaton™ K16 microspeakers is presented. The acoustic liner is made of a circular surface composed of a 10 cm diameter fix support with 7 embedded microspeakers covering 8.5% of th overall surface. Different electrical connections of the microspeakers using no added electronic circuit are tested and...
This paper will present wafer level packaging approaches and results for MEMS encapsulation and integration applied to resonators. The core technologies involve interposer fabrication with Through-Silicon Vias (TSV), temporary wafer bonding for thin wafer handling and wafer bonding for metallic sealing under vacuum and for formation of electrical interconnects. Seal rings based on AuSn metallurgy...
This paper presents the design of a novel multiple-shell vibratory ring gyroscope with increased capacitance for actuation and detection. The multiple shell ring gyroscope is formed as several concentering cylindrical shells with enough space between them to place electrodes in the middle. The structure yields in-plane degenerate flexural modes that are utilized to sense rotation along the normal...
We report quartz level temperature stability of piezoelectrically driven silicon MEMS resonators. Frequency stability of better than ±10 ppm is measured for 23 MHz extensional mode resonators over a temperature range of T = −40 … + 85°C. The temperature compensation mechanism is entirely passive, relying on the tailored elastic properties of heavily doped silicon with a doping level of n > 1020...
In this study, we propose a novel dye-sensitized solar cell (DSSC) structure that employs a quantum dot/semiconductor silicon (QD/Si) coaxial nanorod array to replace the conventional dye/TiO2/TCO photoelectrode. We replaced the backlight input mode with top-side illumination and used a quantum dot to replace dye as the light-absorbing material. Photon-excited photoelectrons can be effectively transported...
Beam structure is widely used for MEMS (Micro-electromechanical Systems) design, the mechanical properties of beam structure are of great importance to guide the design of MEMS devices. Among the many properties, stress rupture properties are studied in this paper. The sensor based on piezoresistive effect with a specially designed cross-beam structure is proposed for stress rupture properties measurement...
We experimentally demonstrate the use of simple MEMS microcantilevers as an efficient way to achieve dynamic manipulation of terahertz waves. An array of subwavelength sized microcantilevers acts as metamaterial, which can be electrostatically tuned to provide active control of light-matter interaction. The proposed metamaterial shows tuning range of 0.3 THz, which is further improved to 0.36 THz,...
This paper gives a detail description of a silicon vibration beam accelerometer which was fabricated by SOI technology and encapsulated in a wafer level vacuum package. The wafer level package gives advantage of small size and low cost, but also produce additional residual stresses that increased the temperature coefficient of the vibration beams. To solve this problem, the sensing structure was redesigned...
We report a technique for defining high aspect ratio electrostatic gaps in micromachined glassblown spherical resonators. The approach is based on intentionally allowing a physical contact between the resonator and electrode structure, hence “collapsed electrodes”, then releasing and metalizing the electrodes and resonator. We utilized 500 um SOI electrodes in the glassblowing fabrication process,...
A piezoelectric MEMS with wake up function, Power down interrupt generator (PDIG), for inertial sensor systems is reported. The aluminum nitride based MEMS generates electric signals intrinsically in result of an inertial accelerations. The PDIG is optimized for maximum charge and voltage sensitivity. The charge sensitivity for a single electrode designed PDIG is measured with 40.1 pC/g and the maximum...
A new optical MEMS silicon pressure sensor for use in high temperature (up to 450°C) and high radiation environments has been developed. Preliminary tests of the pressure sensor integrated with the components of the optical detection system and software has showed accurate detection of pressure by purely optical system.
Micro-cantilevers have rapidly developed in to a new sensor technology because of their features like small size, fast response and high sensitivity. Conventional methods for fabricating microcantilevers are centred either etching in glass and silicon or using lithography. The major problem is that the traditional method to fabricate microcantilevers are not only expensive but also time consuming...
In this work, silicon dioxide layers are deposited by RF sputtering technique at low temperatures for micro electro mechanical systems (MEMS) and CMOS applications. Due to incompatibility of thermally grown oxide in CMOS and MEMS applications, sputtered oxides shown good alternative method for oxide depositions. The sputtered layers shown similar characteristics as thermal oxides. FTIR, AFM and SEM...
In this report, we demonstrate a method to enhance the controllability of MEMS tunable metamaterial by isolating the electrical routing of alternate lines in the metamaterial unit cell array. The metamaterial consists of alternate lines of split ring resonators with two released heights. This allows for two independent tuning characteristics for a single MEMS metamaterial by selecting between the...
This paper demonstrates the effect of nonlinear elasticity on the coupling between different bulk modes of silicon MEMS resonators. From experimental data, we observe that the coupling has a strong dependence on the resonant mode order, the mode shape of the coupled modes, as well as the doping type / concentration, and crystal orientation, leading to a variety of complex and potentially useful phenomena.
This paper demonstrates the feasibility of a novel fabrication approach of MEMS resonators above standard CMOS circuitry and with zero-level vacuum package. As a proof of concept a monolithical CMOS-MEMS-closed loop oscillator showing dual-clock capabilities (11.9 MHz and 24.5 MHz) is presented. These two frequencies correspond to two different resonator modes, specifically the torsional and vertical...
We demonstrate a radio frequency (RF) probe based on microelectromechanical systems (MEMS) design and processing technologies. The probe responds to the current needs of microelectronics requiring microwave characterization of nanoscale devices and systems having micrometer pad sizes. The use of MEMS technologies enables the probe contact pad area dimensions to be reduced by a three orders of magnitude...
This paper reports on a fabrication method of three-dimensional micro structures supported by a Parylene thin film. The three-dimensional structure formation procedure starts with an out-of-plane actuation of the Si surface micromachined structure coated with a thin Parylene film. At the same time of the actuation, the environmental temperature was elevated above the glass transition temperature T...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.