This invention provides electromechanical resonators based on metal chalcogenide nanotubes. The invention further provides methods of fabrication of electromechanical resonators and methods of use of such electromechanical resonators.

There are disclosed various apparatuses and methods for tuning a resonance frequency. In some embodiments there is provided an apparatus (200) comprising at least one input electrode (202, 204) for receiving radio frequency signals; a graphene foil (210) for converting at least part of the radio frequency signals into mechanical energy; at least one dielectric support element (212) to support the graphene foil (210) and to space apart the at least one input electrode (202, 204) and the graphene foil (210). The graphene foil (210) has piezoelectric properties. In some embodiments there is provided a method comprising receiving radio frequency signals by at least one input electrode (202, 204) of an apparatus (200); providing a bias voltage to the apparatus (200) for tuning the resonance frequency of the apparatus (200); and converting at least part of the radio frequency signals into mechanical energy by a graphene foil (210) having piezoelectric properties.

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.

Systems and methods to amplify the response of a MEMS micro-oscillator by driving the MEMS device at its electrical and mechanical resonance frequencies, simultaneously. This enhances the MEMS mechanical sensitivity to electrical excitation and increases the voltage across the MEMS capacitor. Moreover, using a combination of two input signals at different frequencies (beat signal) may be used to achieve double resonance in any MEMS device, even if its natural frequency is far from its electrical resonance.

Embodiments of a tunable bandpass microelectromechanical (MEMS) filter are described. In one embodiment, such a filter includes a pair of arch beam microresonators, and a pair of voltage sources electrically coupled to apply a pair of adjustable voltage biases across respective ones of the pair of arch beam microresonators. The pair of voltage sources offer independent tuning of the bandwidth of the filter. Based on the structure and arrangement of the filter, it can be tunable by 125% or more by adjustment of the adjustable voltage bias. The filter also has a relatively low bandwidth distortion, can exhibit less than 2.5 dB passband ripple, and can exhibit sideband rejection in the range of at least 26 dB.

A method of manufacturing a nanoelectromechanical resonator allows for uniform tuning of a resonant frequency. The nanoelectromechanical resonator can be mass produced and used to sense the presence of a selected gas.

A method for manufacturing a resonator that effectively addresses variations in resistivity for each wafer. The method for manufacturing a resonator includes forming a Si oxide film on a surface of a degenerated Si wafer, where the Si oxide film has a thickness set that is based on the doping amount of impurity in the degenerated Si wafer.

The present disclosure provides an aerosol sensing method. The aerosol sensing method includes steps of providing an entering process, providing a particle collecting process and providing a measuring process. The entering process is to allow an aerosol to enter a chamber of a thermal-piezoresistive oscillator-based aerosol sensor, and a thermal-piezoresistive resonator is disposed in the chamber. The particle collecting process is to allow particulate matters in the aerosol to land on at least one proof-mass of the thermal-piezoresistive resonator when the thermal-piezoresistive resonator is not driven. The measuring process is to use an electrical signal to drive the thermal-piezoresistive resonator and measure a resonant frequency of the thermal-piezoresistive resonator. The particle collecting process and the measuring process are operated in a repetitive cycle for measuring changes of the resonant frequency of the thermal-piezoresistive resonator to measure the particulate matters of the aerosol.

Provided are a resonator, a method of manufacturing the resonator, and a strain sensor and a sensor array including the resonator. The resonator is provided to extend in a lengthwise direction from a support. The resonator includes a single crystal material and is provided to extend in a crystal orientation that satisfies at least one from among a Young's modulus and a Poisson's ratio, from among crystal orientations of the single crystal material.

A passband filter includes a first and second microelectromechanical resonator system, each including a resonating beam, a drive electrode, and a sense electrode. An AC input signal is coupled to the drive electrode of the first and second microelectromechanical resonator system. A differential-to-single ended amplifier has a first input and second input respectively coupled to the sense electrodes of the first and second microelectromechanical resonator systems. An output of the differential-to-single ended amplifier is an output of the passband filter that provides a bandpass filtered signal of the AC input signal. A DC bias signal is coupled to the resonating beams of the first and second microelectromechanical resonator systems. The first microelectromechanical resonator system exhibits a hardening nonlinear behavior defining an upper stop frequency of the passband and the second microelectromechanical resonator system exhibits a softening nonlinear behavior defining a lower stop frequency of the passband.