U.S. Philips Corporation

Nxp B.v.

Koninklijke Philips Corporation N.v.

Triquint Semiconductor Corporation

Robert Frederick Milsom

Mareike K Klee

Olaf Wunnicke

Christof Metzmacher

Hans Peter Loebl

Hans-Peter Loebl

Rainer Kiewitt

Jaap Ruigrok

Wilhelm Georg Hermann

Uwe Mackens

Wolfgang Brand

Hans Peter L&ouml;bl

Martinus Hermanus Wilhemus Maria Van Delden

Hans-Peter Löbl

Hans Peter Löbl

Kevin Robert Boyle

Andreas Bernardus Maria Jansman

Frederik Willem Maurits Vanhelmont

John M Schofield

Antonius J M De Graauw

Robert J Murray

Frederik W M VanHelmont

Kevin J Scott

Arthur J Wachters

Andreas B M Jansman

Godefridus P Maas

Rene Du Cloux

Ian Flinn

A bulk acoustic wave, BAW, resonator device comprising first and second metal layers () and an intervening piezoelectric layer (), the first metal layer () comprising spaced first and second portions (), wherein the first and second portions () are each arranged as a plurality of interconnected fingers (), and wherein each of the plurality of fingers () of the first portion () is acoustically coupled to at least one of the fingers () of the second portion (). In one embodiment the fingers of the first portion () are interlaced with the fingers () of the second portion (), thereby providing direct coupling. In another embodiment the acoustic coupling between the fingers of the first and second portions is provided indirectly by further portions () of the first metal layer ().

Bulk acoustic wave resonator device

A thin-film bulk acoustic wave (BAW) resonator, such as SBAR or FBAR, for use in RF selectivity filters operating at frequencies of the order of 1 GHz. The BAW resonator comprises a piezoelectric layer () having first and second surfaces on opposing sides, a first electrode () extending over the first surface, and a second electrode () extending over the second surface, the extent of the area of overlap (R) of the first and second electrodes determining the region of excitation of the fundamental thickness extensional (TE) mode of the resonator. The insertion loss to the resonator is reduced by providing a dielectric material () in the same layer as the first electrode () and surrounding that electrode. The material constituting the dielectric material () has a different mass, typically between 5% and 15%, from the material comprising the first electrode () it surrounds. The mass of the dielectric material () can be lower or higher than the mass of the first electrode (). Planarisation of the dielectric material () enhances the performance of the device.

Thin-film bulk-acoustic wave (BAW) resonators

A multi-mode radio module () comprises a terminal () for connection to an antenna (). A transmitting branch (DCS/PCS) and a branching circuit are coupled to the terminal (). The branching circuit comprises at least a first and a second branch for receiving signals in first and second frequency bands (DCS, PCS), respectively. Each of the first and second branches comprise, respectively, a phase shifting circuit (PS, PS), a BAW or SAW band pass filter (RXF, RXF) coupled to the phase shifting circuit, the bandwidth of the filter being selected to pass a wanted signal in one of the first and second frequency bands but reject an unwanted signal in the other of the second and first frequency bands, and a low noise amplifier (LNA, LNA) coupled to an output of the band pass filter. The response of each of the band pass filters (RXF, RXF) is phase shifted to present an open circuit at the wanted frequency in the other branch. Each of the phase shifting circuits (PS, PS) is impedance transforming so that higher impedance filters can be used.

High frequency module

An electro-acoustic resonator () of the membrane or FBAR type () or the solidly-mounted or SBAR type (), with electrodes comprising a single conducting layer or multiple conducting layers, i.e. sandwich construction () with an optimum coupling factor kr and thus an improved filter bandwidth. The optimum coupling factor kr is achieved by the arrangement that the top electrode () is thinner than the bottom electrode (). The coupling factor is independent of the resonator's layout defined by the mask.

Electro-acoustic resonator with a top electrode layer thinner than a bottom electrode layer

A ladder filter comprising a plurality of bulk acoustic wave resonators, the resonators comprising a plurality of series resonators series resonators in series between an input terminal and an output terminal of the filter, and one or more shunt resonators each connected between a junction between two series resonators and a common terminal, the series resonators comprising an input series resonator connected to the input terminal and an output series resonator connected to the output terminal, and wherein the shunt resonators are designed to satisfy: a unity aspect ratio and wherein the series resonators are designed to satisfy an aspect ratio different from unity. The aspect ratio is defined as the ratio of length to width of the resonator.

Ladder-type thin-film bulk acoustic wave filter

In order to provide a resonator structure () in particular a bulk-acoustic-wave (BAW) resonator, such as a film BAW resonator (FBAR) or a solidly-mounted BAW resonator (SBAR), comprising at least one substrate (); at least one reflector layer () applied or deposited on the substrate (); at least one bottom electrode layer (), in particular bottom electrode, applied or deposited on the reflector layer (); at least one piezoelectric layer (), in particular C-axis normal piezoelectric layer, applied or deposited on the bottom electrode layer (); at least one top electrode layer (), in particular top electrode, applied or deposited on the bottom electrode layer () and/or on the piezoelectric layer () such that the piezoelectric layer () is in between the bottom electrode layer () and the top electrode layer (), it is proposed that at least one dielectric layer () applied or deposited in and/or on at least one space in at least one region of non-overlap between the bottom electrode layer () and the top electrode layer (). The invention is also concerned with a method of making such resonator structure a its use.

Resonator structure and method of producing it

The invention relates to an arrangement with two piezoelectric layers () and to a method of operating the arrangement as a filter. One () of the two piezoelectric layers () in the arrangement is situated between an electrode () and a middle electrode (), and the other one () of the two piezoelectric layers () is positioned between another electrode () and said middle electrode () such that a bulk acoustic wave resonator is formed. The one and the other electrode () and the middle electrode () are connected to circuitry means for applying high-frequency signals to at least one of the two piezoelectric layers () such that the bulk acoustic wave resonator has at least one resonance frequency when the circuitry means are in one switching state, and that the bulk acoustic wave resonator has at least one other resonance frequency different from the at least one resonance frequency when the circuitry means are in another switching state.

Arrangement with two piezoelectric layers, and method of operating a filter device

A filter structure, comprising a first signal line, a second signal line, a third signal line and a fourth signal line, said first and third signal lines defining an input port and said second and fourth signal lines defining an output port of a section of said filter structure, said section being defined by a first bulk acoustic wave resonator (A) which is connected between said first signal line and said second signal line, a second bulk acoustic wave resonator (G) which is connected between said third signal line and said fourth signal line, a third bulk acoustic wave resonator (C) which is connected between said first signal line and said fourth signal line, and a fourth bulk acoustic wave resonator (E) which is connected between said second signal line and said third signal line; is characterized in that a frequency pulling factor defined d of at least one of said acoustic wave resonators is non-zero, said frequency pulling factor d being defined by for first and second bulk acoustic wave resonators having a resonant frequency fr, and for third and fourth bulk acoustic wave resonators having an anti-resonant frequency fa, fbeing the centre frequency of the filter structure and k the coupling factor of respective resonators.

Filter structure

The invention relates to a filter device equipped with at least one bulk acoustic wave resonator, which comprises a resonator unit and a reflection element () comprising several layers (). The layers () each comprise a mixture of at least two materials. Within each layer (), the composition of the mixture varies continuously and periodically relative to the layer thickness.

Filter system comprising a bulk acoustic wave resonator

The invention relates to a filter device equipped with at least one bulk acoustic wave resonator, which comprises a resonator unit and a reflection unit. The resonator unit comprises a first () and a second electrode () together with a textured piezoelectric layer () between the first () and second () electrodes.

Filter system with bulk wave resonator having a reflection layer composition that varies with the layer thickness

The invention describes a tunable filter arrangement with at least two resonators which are coupled to one another and of which at least one is connected to a capacitor with tunable capacitance. The electrical properties of the resonator, and thus the overall filter characteristic, can be changed through a change in the capacitance of the capacitor. Furthermore, a transmitter, a receiver, a mobile telephone device, and a wireless data transmission system comprising such a filter arrangement are disclosed, as is a tunable bulk acoustic wave resonator.

Tunable piezoelectric filter arrangement using a dielectric material with a voltage-dependent dielectric constant

The invention describes a tunable filter arrangement with a plurality of resonators which are coupled to one another and of which there is at least one which comprises a piezoelectric component made of a ferroelectric material and to which a DC voltage source is connected. The application of a DC voltage to the resonator renders it possible to change its electrical properties and thus the overall filter characteristic. Furthermore, a transmitter, a receiver device, and a mobile telephone device with such a filter arrangement are disclosed, aswell as a tunable bulk acoustic wave resonator.

Tunable filter arrangement comprising resonators with reflection layers

A ladder filter comprises series and shunt resonators ( ). The or each shunt resonator ( ) has a static capacitance which is more than four times the static capacitance of the input or output series resonators ( ). This provides increased shunt resonator capacitance which reduces the effective coupling across the a series-shunt section, thereby enabling a smaller number of series-shunt filter sections to used to achieve good stop-band rejection, while still providing good performance in the pass-band. The invention is based on the recognition that filter bandwidth can be traded for improved out-of-band rejection.

Bulk acoustic wave filter with optimized series and shunt resonator static capacitances

A bulk acoustic wave device has a number of resonator elements ( ) which are laterally spaced such that a signal ( ) applied between to one resonator element ( ) at a resonant frequency of the device is coupled to the other resonator elements ( ) by acoustic coupling between piezoelectric layers of the resonator elements ( ). There are two outer resonator elements ( ) and at least one inner resonator element ( ). The terminals of the inner resonator elements are electrically connected together. This connection provides an AC short which eliminates the effect of the parasitic capacitances of the inner resonator elements, and provides electromagnetic shielding between the input and output of the device, by reducing the parasitic capacitance between the input and output upper electrodes.

Bulk acoustic wave device

A method of, and apparatus for, obtaining a representation of an electrical circuit (,) suitable for time-domain simulation. The electrical circuit comprises a physical structure (,), which is modelled using electromagnetic field analysis, and also comprises a remainder circuit (,) of circuit components which are interconnected with the physical structure. The electromagnetic field analysis is capable of generating at least a high-frequency equivalent circuit which is representative of the physical structure (,) and is valid at the operating frequency of the circuit but not at DC. The method comprises including a set of DC sources (E,to E,) to ensure that, in a time-domain simulation, improved DC bias conditions are provided for any non-linear components in the remainder circuit. The DC sources may be voltage sources in each interconnection, current sources between each interconnection and a zero voltage reference interconnection, or a combination of the two.

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Redhill, United Kingdom

Robert Frederick Milsom