Abstract: A BAW resonator (BAWR) with improved power durability and improved heat resistance is provided. The resonator comprises a layer stack with a piezoelectric material (PM) between a bottom electrode (ELI) and a top electrode (EL2) and a shunt path parallel (PCPP) to the layer stack provided to enable an RF signal to bypass the layer stack, e.g. to ground (GND). The shunt path (PCPP) has a temperature dependent conductance with a negative temperature coefficient, NTC, of resistance. When the temperature of the device rises due to high power operation, currents that would otherwise permanently damage the device are shunted to ground or another dedicated terminal by the temperature dependent shunt path. Upon cooling down normal operation is resumed.

Abstract: A BAW resonator (BAWR) with improved power durability and improved heat resistance is provided. The resonator comprises a layer stack with a piezoelectric material (PM) between a bottom electrode (ELI) and a top electrode (EL2) and a shunt path parallel (PCPP) to the layer stack provided to enable an RF signal to bypass the layer stack, e.g. to ground (GND). The shunt path (PCPP) has a temperature dependent conductance with a negative temperature coefficient, NTC, of resistance. When the temperature of the device rises due to high power operation, currents that would otherwise permanently damage the device are shunted to ground or another dedicated terminal by the temperature dependent shunt path. Upon cooling down normal operation is resumed.

Abstract: An electro-acoustic transducer and an electro-acoustic component including an electro-acoustic transducer are disclosed. In an embodiment the transducer includes a first and a second bus bar, a plurality of electrode fingers and a plurality of two or more sub tracks, wherein each electrode finger is electrically connected to one of the bus bars, wherein each sub track extends along a longitudinal direction, wherein all sub tracks are arranged one next to another in a transversal direction, wherein at least a first of the sub tracks includes segments of the electrode fingers and has an associated sub track with segments of the electrode fingers, wherein the segments of the electrode fingers of the first sub track are shifted by a distance S=?/2 along the longitudinal direction relative to the segments of the electrode fingers of the associated sub track, and wherein ? is an acoustic wavelength.

Abstract: An electro-acoustic transducer and an electro-acoustic component including an electro-acoustic transducer are disclosed. In an embodiment the transducer includes a first and a second bus bar, a plurality of electrode fingers and a plurality of two or more sub tracks, wherein each electrode finger is electrically connected to one of the bus bars, wherein each sub track extends along a longitudinal direction, wherein all sub tracks are arranged one next to another in a transversal direction, wherein at least a first of the sub tracks includes segments of the electrode fingers and has an associated sub track with segments of the electrode fingers, wherein the segments of the electrode fingers of the first sub track are shifted by a distance S=?/2 along the longitudinal direction relative to the segments of the electrode fingers of the associated sub track, and wherein ? is an acoustic wavelength.

Abstract: A surface acoustic wave filter includes a ?-rotated Y-cut X-propagation lithium niobate substrate. The cut angle ranges from 20° to 40°. An interdigital transducer can be used for exciting a surface acoustic wave that is formed on the substrate.

Abstract: A surface acoustic wave filter includes a ?-rotated Y-cut X-propagation lithium niobate substrate. The cut angle ranges from 20° to 40°. An interdigital transducer can be used for exciting a surface acoustic wave that is formed on the substrate.

Abstract: The low Ta impurity content in pyrochlore ore makes it unnecessary to use a solvent extraction process to separate Nb from Ta. Consequently, niobium pentoxide powders using this ore can be produced at lower cost than competing mining/refining approaches, but in turn contain significant amounts of Ta impurities. SAW wafers are grown from melts produced by reacting niobium pentoxide powders containing Ta impurities at levels of 200 ppm or more by weight. Given proper amounts of starting powders, crystals can be grown with good yields and reproducible properties that satisfy typical SAW wafer specifications. The consistency across various lots of powders may be further improved by adding an appropriate amount of Ta pentoxide to the starting powders.

Abstract: The low Ta impurity content in pyrochlore ore makes it unnecessary to use a solvent extraction process to separate Nb from Ta. Consequently, niobium pentoxide powders using this ore can be produced at lower cost than competing mining/refining approaches, but in turn contain significant amounts of Ta impurities. SAW wafers are grown from melts produced by reacting niobium pentoxide powders containing Ta impurities at levels of 200 ppm or more by weight. Given proper amounts of starting powders, crystals can be grown with good yields and reproducible properties that satisfy typical SAW wafer specifications. The consistency across various lots of powders may be further improved by adding an appropriate amount of Ta pentoxide to the starting powders.

Abstract: A surface acoustic wave filter includes first and second channels, each channel including at least one input transducer and one input transducer. The transfer functions of the first channel and of the second channel are in phase in the passband of the filter and in antiphase in the rejection band of the filter. The filter enables the use of frequency responses for each channel, with wide bands enabling high reduction of the size of the filter while at the same time reducing the rejection band of the total filter. Such a filter may find particular application to mobile telephony.