Abstract: In a method for manufacturing a piezoelectric oscillating circuit in thin film technology, wherein the oscillating circuit includes a predetermined natural frequency and a plurality of layers, first of all at least a first layer of the piezoelectric oscillating circuit is generated. Subsequently, by processing the first layer a frequency correction is performed. Subsequently, at least a second layer of the piezoelectric oscillating circuit is generated and processed for performing a second frequency correction.

Abstract: An apparatus includes a first bulk acoustic wave (BAW) device including a first impedance and a second BAW device including a second impedance, wherein the first and second impedances are different and the first and second BAW devices are acoustically coupled.

Abstract: In one embodiment, a method of producing a resonator in thin-film technology is described. The resonator comprises a piezoelectric layer arranged at least partially between a lower electrode and an upper electrode, the resonator being formed over a substrate. The method comprises: forming the lower electrode of the resonator over the substrate; depositing and patterning an insulating layer over the substrate, the insulating layer comprising a thickness substantially equal to a thickness of the lower electrode; removing a portion of the insulating layer to partially expose a surface of the lower electrode; removing a portion of the insulating layer over the surface of the lower electrode by chemical mechanical polishing; forming the piezoelectric layer over the lower electrode; and producing the upper electrode on the piezoelectric layer.

Abstract: Apparatus for housing a micromechanical structure, and a method for producing the housing. The apparatus has a substrate having a main side on which the micromechanical structure is formed, a photo-resist material structure surrounding the micromechanical structure to form a cavity together with the substrate between the substrate and the photo-resist material structure, wherein the cavity separates the micromechanical structure and the photo-resist material structure and has an opening, and a closure for closing the opening to close the cavity.

Abstract: In a method of producing an electrode for a resonator in thin-film technology, the electrode of the resonator is embedded in an insulating layer such that a surface of the electrode is exposed, and that a surface defined by the electrode and the insulating layer is substantially planar.

Abstract: A method for manufacturing a coupled resonator device includes forming a first part of a plurality of layers, trimming an exposed layer of the first part and forming a remaining part of the plurality of layers. The coupled resonator device includes a stack of the plurality of layers, the plurality of layers including a first piezo-layer with a first and a second electrode layer sandwiching the first piezo-layer, a second piezo-layer with a first and a second electrode layer sandwiching the second piezo-layer, the first and second piezo-layers being acoustically coupled to each other.

Abstract: An apparatus includes a first bulk acoustic wave (BAW) device including a first impedance and a second BAW device including a second impedance, wherein the first and second impedances are different and the first and second BAW devices are acoustically coupled.

Abstract: In a method for manufacturing a piezoelectric oscillating circuit in thin film technology, wherein the oscillating circuit includes a predetermined natural frequency and a plurality of layers, first of all at least a first layer of the piezoelectric oscillating circuit is generated. Subsequently, by processing the first layer a frequency correction is performed. Subsequently, at least a second layer of the piezoelectric oscillating circuit is generated and processed for performing a second frequency correction.

Abstract: A piezoelectric component comprises at least two stacked crystal filters on a substrate. Each stacked crystal filter comprises a bottom electrode, a first piezoelectric layer arranged above the bottom electrode, a central electrode arranged above the first piezoelectric layer, a second piezoelectric layer arranged above the central electrode, and a top electrode arranged above the second piezoelectric layer. The bottom electrodes are directly connected to one another and the central electrodes are directly connected to one another.

Abstract: A method for manufacturing a coupled resonator device includes forming a first part of a plurality of layers, trimming an exposed layer of the first part and forming a remaining part of the plurality of layers. The coupled resonator device includes a stack of the plurality of layers, the plurality of layers including a first piezo-layer with a first and a second electrode layer sandwiching the first piezo-layer, a second piezo-layer with a first and a second electrode layer sandwiching the second piezo-layer, the first and second piezo-layers being acoustically coupled to each other.

Abstract: In a method for manufacturing a piezoelectric oscillating circuit in thin film technology, wherein the oscillating circuit includes a predetermined natural frequency and a plurality of layers, first of all at least a first layer of the piezoelectric oscillating circuit is generated. Subsequently, by processing the first layer a frequency correction is performed. Subsequently, at least a second layer of the piezoelectric oscillating circuit is generated and processed for performing a second frequency correction.

Abstract: A piezoelectric component comprises at least two stacked crystal filters on a substrate. Each stacked crystal filter comprises a bottom electrode, a first piezoelectric layer arranged above the bottom electrode, a central electrode arranged above the first piezoelectric layer, a second piezoelectric layer arranged above the central electrode, and a top electrode arranged above the second piezoelectric layer. The bottom electrodes are directly connected to one another and the central electrodes are directly connected to one another.

Abstract: Apparatus for housing a micromechanical structure, and a method for producing the housing. The apparatus has a substrate having a main side on which the micromechanical structure is formed, a photo-resist material structure surrounding the micromechanical structure to form a cavity together with the substrate between the substrate and the photo-resist material structure, wherein the cavity separates the micromechanical structure and the photo-resist material structure and has an opening, and a closure for closing the opening to close the cavity.

Abstract: A method for producing a piezoelectric component comprising at least two stacked crystal filters comprises the steps of depositing of the layer stack above the bottom electrode and the subsequent patterning of the upper electrically conductive layer and, if appropriate, second piezoelectric layers. Thus, it is possible, in a simple manner, with a minimum of process steps, to produce a piezoelectric component comprising two stacked crystal filters which are directly connected to one another via their bottom and central electrodes. The piezoelectric component furthermore has the advantage that applications in which a high stop band attenuation is important can be realized with a relatively small number of filter stages. In this case, through the use of at least two stacked crystal filters, it is possible to achieve an excellent out-of-band rejection also for “single-ended signals”.

Abstract: Apparatus for housing a micromechanical structure, and a method for producing the housing. The apparatus has a substrate having a main side on which the micromechanical structure is formed, a photo-resist material structure surrounding the micromechanical structure to form a cavity together with the substrate between the substrate and the photo-resist material structure, wherein the cavity separates the micromechanical structure and the photo-resist material structure and has an opening, and a closure for closing the opening to close the cavity.

Abstract: In a method of producing an electrode for a resonator in thin-film technology, the electrode of the resonator is embedded in an insulating layer such that a surface of the electrode is exposed, and that a surface defined by the electrode and the insulating layer is substantially planar.

Abstract: A BAW resonator includes a first piezoelectric layer made of a material oriented toward a first direction, and a second piezoelectric layer made of a material oriented toward a second direction which is opposed to the first direction. The first piezoelectric layer and the second piezoelectric layer are acoustically coupled with each other.

Abstract: Apparatus for housing a micromechanical structure, and a method for producing the housing. The apparatus has a substrate having a main side on which the micromechanical structure is formed, a photo-resist material structure surrounding the micromechanical structure to form a cavity together with the substrate between the substrate and the photo-resist material structure, wherein the cavity separates the micromechanical structure and the photo-resist material structure and has an opening, and a closure for closing the opening to close the cavity.

Abstract: The invention relates to bulk acoustic wave filters including at least two bulk acoustic wave resonators. Each of these resonators includes at least one first electrode, a piezoelectric layer, and a second electrode. At least two of the bulk acoustic wave resonators have effective resonator surfaces which differ in their surface form and/or surface content. The inventive design of the bulk acoustic wave resonators enables optimal suppression of interference modes without influencing the impedance level of the filter.

Abstract: A semiconductor component is provided having a layer sequence for conversion of acoustic to thermal signals and electrical voltage changes to one another, as well as a process for its production. The layer sequence has a lower electrode, an upper electrode and a layer which is arranged between them and is piezoelectrical or pyroelectrical. An auxiliary layer is arranged between the lower electrode and the layer and is used for homogeneously oriented growth of the layer during the production process. The auxiliary layer preferably consists essentially of amorphous silicon, amorphous silicon oxide or amorphous silicon nitride.