561results about "Electrostatic transducer loudspeakers" patented technology

A pit (52) is formed in a substrate comprising a silicon wafer (51) on a surface of which a silicon oxide thin layer (53) is formed. A sandwich structure (60) comprising a piezoelectric layer (62) and lower and upper electrodes (61, 63) joined to both surfaces of the piezoelectric layer is disposed so as to stride over the pit (52). The upper surface of the lower electrode (61) and the lower surface of the piezoelectric layer (62) joined to the upper surface of the lower electrode are treated so that the RMS variation of the height thereof is equal to 25 nm or less. The thickness of the lower electrode (61) is set to 150 nm or less. According to such a structure, there is provided a high-performance thin film bulk acoustic resonator which are excellent in electromechanical coupling coefficient and acoustic quality factor.

The present invention relates to transducers, their use and fabrication. The transducers convert between mechanical and electrical energy. Some transducers of the present invention include a pre-strained polymer. The pre-strain improves the conversion between electrical and mechanical energy. The present invention also relates to devices including an electroactive polymer to convert between electrical and mechanical energy. The present invention further relates to compliant electrodes that conform to the shape of a polymer included in a transducer. The present invention provides methods for fabricating electromechanical devices including one or more electroactive polymers.

A solid-state transducer is disclosed. The transducer comprises a semi-conductor substrate forming a support structure and having an opening. A thin-film structure forming a diaphragm responsive to fluid-transmitted acoustic pressure is disposed over the opening. The transducer further includes a plurality of semi-conductor supports and tangential arms extending from the diaphragm edge for connecting the periphery of the diaphragm to the supports. The tangential arms permit the diaphragm to rotate relative to the supports to relieve film stress in the diaphragm. The transducer still further includes a plurality of stop bumps disposed between the substrate and the diaphragm. The stop bumps determine the separation of the diaphragm from the substrate when the transducer is biased.

The present invention relates to transducers, their use and fabrication. The transducers convert between mechanical and electrical energy. Some transducers of the present invention include a pre-strained polymer. The pre-strain improves the conversion between electrical and mechanical energy. The present invention also relates to devices including an electroactive polymer to convert between electrical and mechanical energy. The present invention further relates to compliant electrodes that conform to the shape of a polymer included in a transducer. The present invention provides methods for fabricating electromechanical devices including one or more electroactive polymers.

The present invention is directed to a structure comprised of alternating layers of metal and sacrificial material built up using standard CMOS processing techniques, a process for building such a structure, a process for fabricating devices from such a structure, and the devices fabricated from such a structure. In one embodiment, a first metal layer is carried by a substrate. A first sacrificial layer is carried by the first metal layer. A second metal layer is carried by the sacrificial layer. The second metal layer has a portion forming a micro-machined metal mesh. When the portion of the first sacrificial layer in the area of the micro-machined metal mesh is removed, the micro-machined metal mesh is released and suspended above the first metal layer a height determined by the thickness of the first sacrificial layer. The structure may be varied by providing a base layer of sacrificial material between the surface of the substrate and the first metal layer. In that manner, a portion of the first metal layer may form a micro-machined mesh which is released when a portion of the base sacrificial layer in the area of the micro-machined mesh is removed. Additionally, a second layer of sacrificial material and a third metal layer may be provided. A micro-machined mesh may be formed in a portion of the third metal layer. The structure of the present invention may be used to construct variable capacitors, switches and, when certain of the meshes are sealed, microspeakers and microphones.

A MEMS device and a method to manufacture a MEMS device are disclosed. An embodiment includes forming trenches in a first main surface of a substrate, forming conductive fingers by forming a conductive material in the trenches and forming an opening from a second main surface of the substrate thereby exposing the conductive fingers, the second main surface opposite the first main surface.