Patent classifications
H03H2009/02496
Resonator electrode shields
A microelectromechanical system (MEMS) resonator includes a resonant semiconductor structure, drive electrode, sense electrode and electrically conductive shielding structure. The first drive electrode generates a time-varying electrostatic force that causes the resonant semiconductor structure to resonate mechanically, and the first sense electrode generates a timing signal in response to the mechanical resonance of the resonant semiconductor structure. The electrically conductive shielding structure is disposed between the first drive electrode and the first sense electrode to shield the first sense electrode from electric field lines emanating from the first drive electrode.
MEMS RESONATOR ARRAY ARRANGEMENT
A microelectromechanical resonator, including a support structure, a resonator element suspended to the support structure, the resonator element including a plurality of sub-elements, and an actuator for exciting the resonator element into a resonance mode. The sub-elements are dimensioned such that they are dividable in one direction into one or more fundamental elements having an aspect ratio different from 1 so that each of the fundamental elements supports a fundamental resonance mode, which together define a compound resonance mode of the sub-element. The sub-elements are further coupled to each other by connection elements and positioned with respect to each other such that the fundamental elements are in a rectangular array configuration, wherein each fundamental element occupies a single array position, and at least one array position of the array configuration is free from fundamental elements.
Temperature-compensated micro-electromechanical device, and method of temperature compensation in a micro-electromechanical device
A micro-electromechanical device includes a semiconductor substrate, in which a first microstructure and a second microstructure of reference are integrated. The first microstructure and the second microstructure are arranged in the substrate so as to undergo equal strains as a result of thermal expansions of the substrate. Furthermore, the first microstructure is provided with movable parts and fixed parts with respect to the substrate, while the second microstructure has a shape that is substantially symmetrical to the first microstructure but is fixed with respect to the substrate. By subtracting the changes in electrical characteristics of the second microstructure from those of the first, variations in electrical characteristics of the first microstructure caused by changes in thermal expansion or contraction can be compensated for.
METHODS AND DEVICES FOR MICROELECTROMECHANICAL RESONATORS
MEMS based sensors, particularly capacitive sensors, potentially can address critical considerations for users including accuracy, repeatability, long-term stability, ease of calibration, resistance to chemical and physical contaminants, size, packaging, and cost effectiveness. Accordingly, it would be beneficial to exploit MEMS processes that allow for manufacturability and integration of resonator elements into cavities within the MEMS sensor that are at low pressure allowing high quality factor resonators and absolute pressure sensors to be implemented. Embodiments of the invention provide capacitive sensors and MEMS elements that can be implemented directly above silicon CMOS electronics.
Microelectromechanical resonator system with improved stability with respect to temperature variations
A MEMS resonator system has a micromechanical resonant structure and an electronic processing circuit including a first resonant loop that excites a first vibrational mode of the structure and generates a first signal at a first resonance frequency. A compensation module compensates, as a function of a measurement of temperature variation, a first variation of the first resonance frequency caused by the temperature variation to generate a clock signal at a desired frequency that is stable relative to temperature. The electronic processing circuit further includes a second resonant loop, which excites a second vibrational mode of the structure and generates a second signal at a second resonance frequency. A temperature-sensing module receives the first and second signals and generates the measurement of temperature variation as a function of the first variation of the first resonance frequency and a second variation of the second resonance frequency caused by the temperature variation.
MICRO-ELECTRO-MECHANICAL DEVICE WITH REDUCED TEMPERATURE SENSITIVITY AND MANUFACTURING METHOD THEREOF
A microelectromechanical device having a mobile structure including mobile arms formed from a composite material and having a fixed structure including fixed arms capacitively coupled to the mobile arms. The composite material includes core regions of insulating material and a silicon coating.
COUPLED MEMS RESONATOR
A microelectromechanical resonator includes a support structure, a resonator element suspended to the support structure, and an actuator for exciting the resonator element to a resonance mode. The resonator element includes a plurality of adjacent sub-elements each having a length and a width and a length-to-width aspect ratio of higher than 1 and being adapted to a resonate in a length-extensional, torsional or flexural resonance mode. Further, each of the sub-elements is coupled to at least one other sub-element by one or more connection elements coupled to non-nodal points of the of said resonance modes of the sub-elements for exciting the resonator element into a collective resonance mode.
MEMS resonator with a high quality factor
A symmetrical MEMS resonator is disclosed with a high quality factor. The MEMS resonator includes a silicon layer with a top surface and bottom surface opposite the top surface. A pair of first metal layers is provided above the top surface of the silicon layer and a corresponding pair of second metal layers is symmetrically provided below the second surface of the silicon layer relative to the pair of first metal layers. Furthermore, a first piezoelectric layer is disposed between the pair of first metal layers and a second piezoelectric layer is disposed between the pair of second metal layers.
Micro-electro-mechanical device with reduced temperature sensitivity and manufacturing method thereof
A microelectromechanical device having a mobile structure including mobile arms formed from a composite material and having a fixed structure including fixed arms capacitively coupled to the mobile arms. The composite material includes core regions of insulating material and a silicon coating.
Method for producing a batch of acoustic wave filters
A method for the batch production of acoustic wave filters comprises: synthesizing N theoretical filters, each filter defined by a set of j theoretical resonator(s) having a triplet C.sub.0ij,eq, .sub.rij,eq and .sub.aij,eq, these parameters grouped into subsets; determining a reference resonator structure for each subset, naturally having a resonant frequency .sub.r,ref, where .sub.aij,eq<.sub.r,ref<.sub.rij,eq; determining, for each theoretical resonator, an elementary building block comprising an intermediate resonator R.sub.ij, a parallel reactance Xp.sub.ij and/or a series reactance Xs.sub.ij, the intermediate resonator R.sub.ij having a triplet C.sub.0ij, .sub.r,ref and .sub.a,ref, the parameters C.sub.0ij, Xpij and/or Xs.sub.ij defined so the elementary building block has a triplet: C.sub.0ij,eq, .sub.rij,eq and .sub.aij,eq; determining the geometrical dimensions of the actual resonators R.sub.ij of the filters so they have a capacitance C.sub.0ij; producing each actual resonator; associating series and/or parallel reactances with actual resonators in order to form the elementary building blocks.