Abstract: A BAW gyroscope is configured to operate with two pairs of orthogonal modes instead of a single pair in order to mitigate the impact of changes in gaps (e.g., introduced from external stresses such as thermal gradients, external shocks, mechanical stress/torque, etc.). Specifically, the BAW gyroscope resonator is configured to be simultaneously driven to resonate with a two disparate resonant modes (referred to herein as the “fundamental” mode and the “compound” mode), with the same set of drive electrodes used to drive both resonant modes (i.e., all of the drive electrodes are used to drive the two drive modes). When the sensor experiences external rotation, energy couples from the driven modes of vibration to two corresponding orthogonal sense modes via the Coriolis force. The same set of sense electrodes is used to sense both sense modes (i.e., all of the sense electrodes are used to sense the two sense modes).

Abstract: One-axis and two-axis vibratory gyroscopes include a unitary resonator structure conceptually having four beams interconnected in a cross-hatch configuration. While each beam can be considered a unitary piece of material, each beam's attachment to two cross beams conceptually divides the resonant beam into a central section between the attachment points and two tail sections aft of the attachment points. The attachment points are preferably nodal points of the beam with respect to both a drive mode shape and a sense mode shape of the beam for the resonant mode in which the resonator is configured to operate. Thus, the location where two beams intersect is preferably a nodal point for both beams. The tail sections of each beam allow the resonant mode of the resonator to be carefully configured.

Abstract: A single photo mask can be used to define the three critical layers for the piezoelectric MEMS device, specifically the top electrode layer, the piezoelectric material layer, and the bottom electrode layer. Using a single photo mask removes the misalignment source caused by using multiple photo masks. Furthermore, in certain exemplary embodiments, all electrical interconnects use underpass interconnect. This simplifies the process for defining the device electrodes and the process sequence for achieving self-alignment between the piezoelectric element and the top and bottom electrodes. This self-alignment is achieved by using an oxide hard mask to etch the critical region of the top electrode, the piezoelectric material, and the bottom electrode with one mask and different etch chemistries depending on the layer being etched.

Abstract: A BAW gyroscope is configured to operate with two pairs of orthogonal modes instead of a single pair in order to mitigate the impact of changes in gaps (e.g., introduced from external stresses such as thermal gradients, external shocks, mechanical stress/torque, etc.). Specifically, the BAW gyroscope resonator is configured to be simultaneously driven to resonate with a two disparate resonant modes (referred to herein as the “fundamental” mode and the “compound” mode), with the same set of drive electrodes used to drive both resonant modes (i.e., all of the drive electrodes are used to drive the two drive modes). When the sensor experiences external rotation, energy couples from the driven modes of vibration to two corresponding orthogonal sense modes via the Coriolis force. The same set of sense electrodes is used to sense both sense modes (i.e., all of the sense electrodes are used to sense the two sense modes).

Abstract: A single-axis resonating beam gyroscope uses a special arrangement of support tethers that maximizes the Q (quality factor) and minimizes stress sensitivity. The tethers are located at the nodal points of the beam with respect to a predetermined drive mode and are approximately one-fourth the length of the beam. Also, the tethers do not extend above or through the nodal points of the beam, which would be difficult to produce in typical MEMS fabrication processes. Embodiments typically use electrostatic drive and sense transduction. Trim electrodes may be used to compensate for any erroneous modal coupling.

Abstract: One-axis and two-axis vibratory gyroscopes include a unitary resonator structure conceptually having four beams interconnected in a cross-hatch configuration. While each beam can be considered a unitary piece of material, each beam's attachment to two cross beams conceptually divides the resonant beam into a central section between the attachment points and two tail sections aft of the attachment points. The attachment points are preferably nodal points of the beam with respect to both a drive mode shape and a sense mode shape of the beam for the resonant mode in which the resonator is configured to operate. Thus, the location where two beams intersect is preferably a nodal point for both beams. The tail sections of each beam allow the resonant mode of the resonator to be carefully configured.

Abstract: A single photo mask can be used to define the three critical layers for the piezoelectric MEMS device, specifically the top electrode layer, the piezoelectric material layer, and the bottom electrode layer. Using a single photo mask removes the misalignment source caused by using multiple photo masks. Furthermore, in certain exemplary embodiments, all electrical interconnects use underpass interconnect. This simplifies the process for defining the device electrodes and the process sequence for achieving self-alignment between the piezoelectric element and the top and bottom electrodes. This self-alignment is achieved by using an oxide hard mask to etch the critical region of the top electrode, the piezoelectric material, and the bottom electrode with one mask and different etch chemistries depending on the layer being etched.

Abstract: A radio frequency microelectromechanical (RF MEMS) device can comprise an actuation p-n junction and a sensing p-n junction formed within a semiconductor substrate. The RF MEMS device can be configured to operate in a mode in which an excitation voltage is applied across the actuation p-n junction varying a non-mobile charge within the actuation p-n junction to modulate an electric field acting upon dopant ions and creating electrostatic forces. The electrostatic forces can create a mechanical motion within the actuation p-n junction. The mechanical motion can modulate a depletion capacitance of the sensing p-n junction, thereby creating a motional current. At least one of the p-n junctions can be located at an optimal location to maximize the efficiency of the RF MEMS device at high resonant frequencies.

Abstract: A digitally-tunable RF MEMS filter includes a substrate and a plurality of mechanically coupled resonators, wherein a first and a last resonator of the plurality of mechanically coupled resonators are configured to be electrostatically transduced. One or more of the plurality of mechanically coupled resonators are configured to be biased relative to the substrate such that the one or more biased resonators may be brought substantially in contact with the substrate. In a method of digitally tuning an RF MEMS filter having a mechanically coupled resonator array, a DC bias voltage is applied to at least a first resonator and a last resonator of the mechanically coupled resonator array such that motional boundary conditions for the at least first resonator and last resonator are selectable in proportion to the DC bias voltage.

Abstract: A radio frequency microelectromechanical (RF MEMS) device can comprise an actuation p-n junction and a sensing p-n junction formed within a semiconductor substrate. The RF MEMS device can be configured to operate in a mode in which an excitation voltage is applied across the actuation p-n junction varying a non-mobile charge within the actuation p-n junction to modulate an electric field acting upon dopant ions and creating electrostatic forces. The electrostatic forces can create a mechanical motion within the actuation p-n junction. The mechanical motion can modulate a depletion capacitance of the sensing p-n junction, thereby creating a motional current. At least one of the p-n junctions can be located at an optimal location to maximize the efficiency of the RF MEMS device at high resonant frequencies.

Abstract: A digitally-tunable RF MEMS filter includes a substrate and a plurality of mechanically coupled resonators, wherein a first and a last resonator of the plurality of mechanically coupled resonators are configured to be electrostatically transduced. One or more of the plurality of mechanically coupled resonators are configured to be biased relative to the substrate such that the one or more biased resonators may be brought substantially in contact with the substrate. In a method of digitally tuning an RF MEMS filter having a mechanically coupled resonator array, a DC bias voltage is applied to at least a first resonator and a last resonator of the mechanically coupled resonator array such that motional boundary conditions for the at least first resonator and last resonator are selectable in proportion to the DC bias voltage.

Abstract: 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.