摘要:
A multiple coil spring MEMS resonator includes a center anchor and a resonator body (106) including two or more coil springs (102a, 102b) extending in a spiral pattern from the center anchor to an outer closed ring (104). Each pair of coil springs originates from opposing points on the center anchor and extends in the spiral pattern to opposing points on the outer ring. The number of coil springs, the length and the width of the coil springs and the weight of the outer ring are selected to realize a desired resonant frequency. The outer ring (104) comprises perpendicular transducers (108) and may comprise holes (130) to adjust the weight of the outer ring (104). A set of drive electrodes (110) and sense electrodes (112) are attached to the substrate.
摘要:
A tunable Q resonator using a capacitive-piezoelectric transducer provides a flexible top electrode above an AlN resonator. The top electrode can be pulled electrostatically towards the resonator and substrate, forming a frictional contact with either the resonator or the combined resonator-electrode structure to the substrate, allowing for electrical tuning the Q of the resonator. With a sufficient electrostatic bias voltage Vb, the resonator may be completely turned OFF, allowing for an integrated switchable AlN resonator. Such switchable resonator may be integrated into a radio frequency (RF) front end as a digitally selectable band pass filter element, obviating the need for ancillary micromechanical switches in the signal path. The device has been demonstrated with a Q approaching 9,000, together with ON/OFF switchability and electromechanical coupling up to 0.63%. Flexible positioning of the top electrode allows for actively controlling the series resonant frequency of the resonator through changes in capacitive coupling.
摘要:
La présente invention concerne un NEMS doté d'un réseau, de pistes et/ou de lignes conductrices, sur lesquelles on applique des signaux d'excitation symétriques, ce réseau présentant une symétrie selon un axe passant par une ligne ou une piste conductrice de détection acheminant un signal de détection provenant du NEMS, la symétrie du réseau et des signaux permettant de palier au problème de capacités parasites engendrées entre le réseau et la ligne de détection.
摘要:
Embodiments of the invention include micromechanical resonators. These resonators can be fabricated from thin silicon layers. Both rotational and translational resonators are disclosed. Translational resonators can include two plates coupled by two resonate beams. A stable DC bias current can be applied across the two beams that causes the plates to resonate. In other embodiments, disk resonators can be used in a rotational mode. Other embodiments of the invention include using resonators as timing references, frequency sources, particle mass sensors, etc.
摘要:
The invention relates to a micromechanical resonator comprising a substrate (1) of first material (2), a resonator (3) suspended to the supporting structure (1), the resonator (3) being at least partially of the same material (2) as the supporting structure and dimensioned for resonation at a specific frequency f o , coupling means (5) for initiating, maintaining and coupling the resonation of the resonator (3) to an external circuit (6), and the resonator (3) including second material (4), the thermal properties of which being different from the first material (2). In accordance with the invention the resonator (3) includes the second material (4) located concentrated in specific places of the resonator (3).
摘要:
The transducer (1) comprises an electrically conductive resonator element (20) extending in a longitudinal direction having a length (l). It can be elastically deformed by an electrically conductive actuator (30) such that the elastic deformation comprises a change of the length (dl). The resonator element (20) is electrically connected to a first contact area (25) and a second contact area (26) thereby constituting a circuit. In this circuit the resonator element (20) constitutes a resistor with an ohmic resistance (R) which is a function of the length (l+dl). The transducer (1) further comprises a measurement point (28) electrically connected to the circuit for providing an electrical signal which is a function of the resistance (R).
摘要:
A MEMS filter has an input layer for receiving a signal input, and an output layer for providing a signal output, The MEMS filter also has a first resonator and a second resonator coupled to the first resonator such that movement transduced in the first resonator by the signal input causes movement of the second resonator which transduces the signal output. A method of manufacturing a MEMS filter is also disclosed. A dielectric layer is formed on a base. A patterned electrode layer is formed at least in part on the dielectric layer. The base is etched to define a resonator structure. A method of adjusting a desired input impedance and an output impedance of a dielectrically transduced MEMS filter having transduction electrodes coupled to a dielectric film is further disclosed. The method includes adjusting a DC bias voltage on the transduction electrodes.
摘要:
A micro-electro-mechanical transducer (such as a cMUT) is disclosed. The transducer has a base, a spring layer placed over the base, and a mass layer connected to the spring layer through a spring-mass connector. The base includes a first electrode. The spring layer or the mass layer includes a second electrode. The base and the spring layer form a gap therebetween and are connected through a spring anchor. The mass layer provides a substantially independent spring mass contribution to the spring model without affecting the equivalent spring constant. The mass layer also functions as a surface plate interfacing with the medium to improve transducing performance. Fabrication methods to make the same are also disclosed.
摘要:
A micro-electro-mechanical transducer (such as a cMUT) having a non-flat surface is disclosed. The non-flat surface may include a variable curve or slope in an area where a spring layer contacts a support, thus making a variable spring model as the spring layer vibrates. The non-flat surface may be that of a non-flat electrode optimized to compensate the dynamic deformation of the other electrode during operation and thus enhance the uniformity of the dynamic electrode gap during operation. Methods for fabricating the micro-electro-mechanical transducer are also disclosed. The methods may be used in both conventional membrane-based cMUTs and cMUTs having embedded springs transporting a rigid top plate.
摘要:
An electrostatic transducer for micromechanical resonators, in which the electrode gaps are filled with a dielectric material having a much higher permittivity than air. This internal electrostatic transducer has several advantages over both air-gap electrostatic and piezoelectric transduction; including lower motional impedance, compatibility with advanced scaled CMOS device technology, and extended dynamic range. In one aspect, in order to minimize energy losses, the dielectric material has an acoustic velocity which is matched to that of the resonator material. Internal electrostatic transduction can be adapted to excite and detect either vertical modes (perpendicular to the substrate) or lateral modes (in the plane of the substrate). Its increased transduction efficiency is of particular importance for reducing the motional resistance of the latter.