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 resonator device includes a piezoelectric resonator having a detuning layer sequence arranged on the piezoelectric resonator. The detuning layer sequence includes at least a first layer having a high acoustic impedance and a second layer having a low acoustic impedance.

Abstract: A medical electrode is provided for measuring the electrical resistance of the body of a patient, especially an impedance cardiography electrode. The electrode includes a non-conductive, unilaterally adhesive support (1) that is elongated and that forms a connecting strap (1?) at its one end for connecting the electrode with electrical terminals; and two contact strips (2a, 2b) from an electrically conductive aluminum composite film, as the electrode material, that are adhered to the support (1) on the adhesive face thereof. The contact strips (2a, 2b) on their side facing away from the support (1) form a composite structure with a skin-friendly electrically conductive adhesive, leaving free the connection straps or lugs (2a?, 2b?), and the strips bend into connection straps (2a?2b?) at the connecting end of the support (1).

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: A method for producing a layer with a locally adapted or predefined layer thickness profile that can be used for to selectively set the natural frequencies of piezoelectric resonant circuits and/or the impedance of other circuit elements. A layer is applied to a substrate, then measured to determine a difference between the initial layer thickness and the predefined layer thickness profile. An ion beam is then used to etch (mill) the layer until it achieves the predefined layer thickness profile.

Abstract: The invention describes a method for producing a piezoelectric component comprising at least two stacked crystal filters. By means of the deposition of the layer stack above the bottom electrode and the subsequent patterning of the upper electrically conductive layer and, if appropriate, second piezoelectric layer, 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 according to the invention 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: A resonator device includes a piezoelectric resonator having a detuning layer sequence arranged on the piezoelectric resonator. The detuning layer sequence includes at least a first layer having a high acoustic impedance and a second layer having a low acoustic impedance.

Abstract: The resonator comprises a first electrode (E1), a second electrode (E2) and a piezoelectric layer (P) arranged between the above. A first acoustic compression layer (V1) is arranged between the piezoelectric layer (E1) and the first electrode (E1) with a higher acoustic impedance than the first electrode (E1).

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: The layer sequence has a lower electrode (U), an upper electrode (O) and a layer (S) which is arranged between them and is piezoelectrical or pyroelectrical. An auxiliary layer (H) is arranged between the lower electrode (U) and the layer (S) and is used for homogeneously oriented growth of the layer (S) during the production process. The auxiliary layer (H) is preferably composed essentially of amorphous silicon, amorphous silicon oxide or amorphous silicon nitride.