Aspects of this disclosure relate to a capacitive micromachined ultrasonic transducer (CMUT) with a contoured electrode. In certain embodiments, the CMUT has a contoured electrode. The electrode may be non-planar to correspond to a deflected shape of the outer plate. A change in distance between the electrode and the plate after deflection may be greater than a minimum threshold across the width of the CMUT.

Micromachined ultrasonic transducers integrated with complementary metal oxide semiconductor (CMOS) substrates are described, as well as methods of fabricating such devices. Fabrication may involve two separate wafer bonding steps. Wafer bonding may be used to fabricate sealed cavities in a substrate. Wafer bonding may also be used to bond the substrate to another substrate, such as a CMOS wafer. At least the second wafer bonding may be performed at a low temperature.

A method for manufacturing a piezoelectric device that includes a substrate and a vibration portion that can include a membrane or a beam that is directly or indirectly supported by the substrate and arranged above the substrate. Moreover, the vibration portion includes a piezoelectric layer and the method includes forming the vibration portion and adjusting a resonance frequency of the vibration portion by locally subjecting a region including the vibration portion to heat treatment.

A plurality of micro-electro-mechanical system (MEMS) transducers in a phased array are coupled to a flexible substrate using carbon nanotubes (CNTs) for conformal ultrasound scanning. Each transducer comprises a cantilever, magnetic material deposited on the cantilever, and a solenoid positioned relative to the magnetic material. The carbon nanotubes are grown on the cantilever and mechanically couple the transducer to one side of the flexible substrate. The other side of the flexible substrate is applied to a surface of a part under inspection, and the transducers are electrically connected to a processer to cause movement of the cantilevers when the solenoids are energized by the processor. The movement of the cantilevers results in movement of the carbon nanotubes, which imparts a force to the flexible substrate that results in ultrasound waves, which permeate the part. Returns from the ultrasound waves are interpreted by the processor to generate images of the part.

A method for fabricating three-dimensional microstructures is presented. The method includes: disposing a substantially planar reflow material between two molds; heating the reflow material while the reflow material is disposed between the two molds; and reflowing the reflow material towards the bottom surface of one of the molds by creating a pressure gradient across the reflow material. At least one of molds includes geometrics features that help to shape the reflow material and thereby form a complex three-dimensional microstructure.

A sensor chip combining a substrate comprising at least one CMOS circuit, a MEMS substrate and another substrate comprising at least one CMOS circuit in one package that is vertically stacked is disclosed. The package comprises a sensor chip further comprising a first substrate with a first surface and a second surface comprising at least one CMOS circuit; a MEMS substrate with a first surface and a second surface; and a second substrate comprising at least one CMOS circuit. Where the first surface of the first substrate is attached to a packaging substrate and the second surface of the first substrate is attached to the first surface of the MEMS substrate. The second surface of the MEMS substrate is attached to the second substrate. The first substrate, the MEMS substrate, the second substrate and the packaging substrate are mechanically attached and provided with electrical inter-connects.

A device with an out-of-plane electrode includes a device layer positioned above a handle layer, a first electrode defined within the device layer, a cap layer having a first cap layer portion spaced apart from an upper surface of the device layer by a gap, and having an etch stop perimeter defining portion defining a lateral edge of the gap, and an out-of-plane electrode defined within the first cap layer portion by a spacer.

An antenna having radio-frequency (RF) resonators and methods for fabricating the same are described. In one embodiment, the antenna comprises a physical antenna aperture having an array of antenna elements, where the array of antenna elements includes a plurality of radio-frequency (RF) resonators, with each RF resonator of the plurality of RF resonators having an RF radiating element with a microelectromchanical systems (MEMS) device.

Embodiments of multi-frequency excitation are described. In various embodiments, a natural frequency of a device may be determined. In turn, a first voltage amplitude and first fixed frequency of a first source of excitation can be selected for the device based on the natural frequency. Additionally, a second voltage amplitude of a second source of excitation can be selected for the device, and the first and second sources of excitation can be applied to the device. After applying the first and second sources of excitation, a frequency of the second source of excitation can be swept. Using the methods of multi-frequency excitation described herein, new operating frequencies, operating frequency ranges, resonance frequencies, resonance frequency ranges, and/or resonance responses can be achieved for devices and systems.

A structure of micro-electro-mechanical systems (MEMS) electroacoustic transducer is disclosed. The MEMS electroacoustic transducer includes a substrate having a MEMS device region, a diaphragm having openings and disposed in the MEMS device region, a silicon material layer disposed on the diaphragm and sealing the diaphragm, and a conductive pattern disposed beneath the diaphragm in the MEMS device region. Preferably, a first cavity is also formed between the diaphragm and the substrate.