Epcos Ag

Rf360 Singapore Pte. Ltd.

Qualcomm Incorporated

Snaptrack Incorporated

Markus Hauser

Werner Ruile

Ingo Bleyl

Christoph Eggs

Ulrike Roesler

Ulrike Rösler

Markus Mayer

Michael Jakob

Gerd Riha

Edgar Schmidhammer

Anton Leidl

Gerd Scholl

Matthias Knapp

Ulrich Knauer

Wolfgang Sauer

Thomas Ebner

Ulrich Wolff

Stefan Berek

Karl-Christian Wagner

Hans-Peter Kirschner

Andreas Detlefsen

Franz Kubat

Clemens Ruppel

Evelyn Riha

Ralf Thomas

A surface acoustic wave device () is provided using a layered substrate system with a special material and a special cut of a piezoelectric thin film () selected for utilizing Rayleigh mode. The proper choice of the material and the cut of the piezoelectric thin film leads to a low velocity of the excited wave mode, which allows the usage of smaller devices without deteriorating other performance parameters according to specifications.

Thin-film saw device utilizing rayleigh mode

A thin film SAW device comprises a carrier substrate (CA), a TCF compensating layer (CL), a piezoelectric layer (PL), and an IDT electrode (EL) on top of the piezoelectric layer. A functional layer (FL) is arranged between piezoelectric layer and TCF compensating layer to further reduce the TCF. The material properties of the functional layer match those of the piezoelectric layer in view of acoustic velocity, density and stiffness such that they do not deviate from each other by more than 10% without having piezoelectric effect. The functional layer my be of the same crystalline constitution as the useful piezoelectric layer but without piezoelectric properties.

Thin film saw device

An electroacoustic component includes a substrate configured to carry acoustic waves. The electroacoustic component can be a guided bulk acoustic wave (GBAW) device, for example. A structured electric conductive layer is arranged on the substrate and an electrically dielectric layer (for example, aluminum oxide) is also arranged over the substrate.

Electricoacoustic component with structured conductor and dielectric layer

An electroacoustic transducer has reduced loss due to acoustic waves emitted in the transverse direction. For this purpose, a transducer comprises a central excitation area, inner edge areas flanking the central excitation area, outer edge areas flanking the inner edge areas, and areas of the busbar flanking the outer edge areas. The longitudinal speed of the areas can be set so that the excitation profile of a piston mode is obtained.

Electroacoustic transducer having reduced losses due to transverse emission and improved performance due to suppression of transverse modes

The present invention relates to an electroacoustic transducer which is arranged in an acoustic track (AS) and on a piezoelectric substrate () and which has two electrodes () which are arranged on the substrate () and which have interengaging electrode fingers () for exciting acoustic waves. The electrode fingers () of an electrode () are interconnected. The transducer also has means for increasing the mass occupation in a central excitation region (ZAB) which runs parallel to the acoustic track (AS), and the mass occupation in the central excitation region (ZAB) is higher than in an edge region (RB) which adjoins the central excitation region (ZAB) from both sides.

Electroacoustic transducer with reduced losses due to transverse emission and improved performance due to suppression of transverse modes

A SAW filter circuit having improved ESD resistance is specified, in which a series interconnection composed of SAW resonators is interconnected between a first signal port and a dual-mode SAW filter port. The static capacitance of the series interconnection is at most four times the static capacitance of the dual-mode SAW filter transducers interconnected therewith.

SAW filter circuit having improved ESD resistance

A method for producing an electric component including a dielectric layer on a substrate, includes the method steps of applying a metallic layer to the substrate and oxidizing the metallic layer to form a dielectric layer, wherein at least one partial region of the metallic layer is fully oxidized through the entire thickness of the layer.

Method for producing an electric component

A component that operates with acoustic waves includes a substrate including a piezoelectric material, a first electrode plane in which bottom electrode structures including an acoustically active bottom electrode are arranged directly on the substrate, and a top electrode arranged above the bottom electrode plane and which is electrically conductively connected to the bottom electrode structures, wherein excitation of the acoustic waves during operation of the component is effected exclusively or predominantly through the bottom electrode structures.

Construction element that operates with acoustic waves, and method for the manufacture thereof

A component working with guided acoustic waves includes a layer system configured to guide waves in a lateral plane. The layer system includes a piezoelectric layer, electrodes on the piezoelectric layer for exciting the wave, a dielectric layer with an acoustic impedance, and an adjustment layer with an acoustic impedance. A ratio of the acoustic impedance of the adjustment layer to the acoustic impedance of the dielectric layer is greater than 1.5.

Component operated by guided acoustic waves

A component includes a filter having a first structure and a second structure. The component also includes a substrate on which the first and second structures are arranged. The first structure has an approximately uniform layer thickness and an approximately uniform composition. The second structure has an approximately uniform layer thickness and an approximately uniform composition. At least one of the layer thickness or composition of the first structure differs from the layer thickness or composition of the second structure.

Low-loss electro-acoustic component

Elements and methods for forming elements that operate with acoustic waves are disclosed. The element includes a piezoelectric electric substrate that has a first thermal coefficient of expansion, electrically conducting element structures on an upper side of the substrate, a compensation layer on an underside of the substrate, and an SiOlayer over the element structures.

SAW-component having a reduced temperature path and method for the production thereof

An apparatus including a piezoelectric substrate having at least one transducer electrode structure. The structure having a metallization formed by one or more metals with a mean specific density that is at least 50% higher than that of aluminum. The structure having a compensation layer that is applied fully or partially over the metallization. The compensation layer is of a material having a temperature dependence of elastic constants that counteracts the temperature coefficient of frequency of the substrate. The compensation layer has a thickness that is less than 15% of an acoustic wavelength of a wave capable of propagation in the structure.

SAW component having an improved temperature coefficient

An electroacoustic transducer includes a first electrode having first fingers connected to a first bus bar, and a second electrode having second fingers connected to a second bus bar. The first and second fingers interdigitate and terminate at ends. The ends of the first and second fingers abut gaps between the first and second electrodes. An acoustic wave of wavelength &#x3bb; is excitable at a resonant frequency. The acoustic wave has a longitudinal and a transverse excitation profile and a longitudinal and a transverse energy density profile, where the longitudinal excitation profile is approximately constant and different from the longitudinal energy density profile, and the transverse excitation profile substantially corresponds to the transverse energy density profile. Transverse positions of the gaps relative to the first and second bus bars vary to substantially correspond to the transverse excitation profile across the gaps.

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Feldafing, Germany

Markus Hauser