An ultra-miniature PCS duplexer uses thin-film bulk wave acoustic resonator (FBAR) technology. FBAR resonators are made using aluminum nitride for the piezoelectric material and silicon as the substrate. It has better than -52 dB rejection for the receive (Rx) filter in the transmit (Tx) band and pass-band insertion losses are on the order of 2 dB (Tx) and 3 dB (Rx). Performance is comparable to that of much larger ceramic duplexers.

Ultra-miniature high-Q filters and duplexers using FBAR technology

The current invention provides for encapsulated release structures, intermediates thereof and methods for their fabrication. The multi-layer structure has a capping layer, that preferably comprises silicon oxide and/or silicon nitride, and which is formed over an etch resistant substrate. A patterned device layer, preferably comprising silicon nitride, is embedded in a sacrificial material, preferably comprising polysilicon, and is disposed between the etch resistant substrate and the capping layer. Access trenches or holes are formed in to capping layer and the sacrificial material are selectively etched through the access trenches, such that portions of the device layer are release from sacrificial material. The etchant preferably comprises a noble gas fluoride NGF 2x (wherein Ng=Xe, Kr or Ar: and where x=1, 2 or 3). After etching that sacrificial material, the access trenches are sealed to encapsulate released portions the device layer between the etch resistant substrate and the capping layer. The current invention is particularly useful for fabricating MEMS devices, multiple cavity devices and devices with multiple release features.

Microelectronic mechanical system and methods

A novel geometry, the geometry of Space-Filling Curves (SFC) is defined in the present invention and it is used to shape a part of an antenna. By means of this novel technique, the size of the antenna can be reduced with respect to prior art, or alternatively, given a fixed size the antenna can operate at a lower frequency with respect to a conventional antenna of the same size.

Space-filling miniature antennas

A duplexer has an asymmetrical antenna port and a symmetrical reception output, and therefore can be interconnected (without any intermediate stages) to an amplifier with a differential input. A reception bandpass filter is arranged in the reception path of the duplexer. The reception bandpass filter can have the functionality of a balun. The transmission input of the duplexer can be designed symmetrically, in which case a transmission bandpass filter arranged in the transmission path should be designed symmetrically on the input side. The impedance of the antenna port of the duplexer can differ from the impedance of the reception output or the transmission input. No intermediate stages (such as a balun or—in cases of impedances that differ between the duplexer and its corresponding amplifier—an impedance transformer) are required between the duplexer and the amplifier that is interconnected (whether before or after) in the transmission or reception path.

Duplexer with extended functionality

An electronic component having a multi-layered printed circuit board made of an organic material, a plurality of electronic components mounted in a face-down position on the multi-layered printed circuit board, a metal cover for covering the plurality of electronic components remaining a space or a cavity between the top surface of the printed circuit board and the inner surface of the metal cover having a flange surrounding the outskirts of the metal cover to be adhered to the top surface of the multi-layered printed circuit board, and a heat conductive member packed between the bottom surface of the electronic components, wherein the multi-layered printed circuit board has at least one through-hole vertically penetrating the multi-layered printed circuit board at a location corresponding to the flange and is lined by a metal film, and the multi-layered printed circuit board has a heat conductive layer arranged along the rear surface of the multi-layered printed circuit board, the heat conductive layer being connected to a metal lining of the through-hole.

Electronic component utilizing face-down mounting

In a duplexer, phase matching circuit patterns corresponding to filter chips are formed on a surface layer of a multi-layer ceramic package provided with filter chips having different central frequencies. An end of each of the phase matching circuit patterns is connected to a common terminal pattern.

Surface acoustic wave filter duplexer comprising a multi-layer package and phase matching patterns

This paper describes a design technology of a small antenna duplexer, especially package conditions, by using ladder type SAW filters. This requires not only optimizing the filter design but also the electrode materials and the package design which has matching circuitry for the duplexer configuration. The matching circuitry was incorporated into a microstrip structural pattern which is designed onto the surface of a multilayer ceramic package. To avoid the deterioration of in-band VSWR and reflection coefficient of the stop-band after rotating phase caused by the matching pattern, the characteristic impedance of the matching pattern was designed to be 1.06 times Zo. To obtain the high stop-band attenuation and Tx-Rx isolation characteristics, the package parasitic inductance was used by the multilayer structure design of the package.

A design of antenna duplexer using ladder type SAW filters

For smaller handheld telephones, we have developed a small antenna duplexer. This paper describes the fabrication and characteristics of our duplexer. Our package, which comprises two cavities and impedance control circuits with a strip line, has a multilayered structure. The package is made of glass-ceramic of size 7.5t8.5t2.5 mm3. The conductor patterns of the package are made of Cu. For the SAW filter of the duplexer, we used the ladder type filter composed of one-port SAW resonators. Typical frequency response characteristics of the AMPS specification are 2.5/3.5 dB.(transmitter/receiver) insertion loss at maximum in the 25 MHz passband, and 35/29 dB stopband rejection. We also improved the filter lifetime using a three-layer Al-Cu/Cu/Al-Cu electrode film structure to 300 times the lifetime of a comparable Al-Cu single-layer filter. From the Arrhenius plot, the lifetime was estimated at more than 500000 hours at 120dC for an input power of 1 W

Development of small antenna duplexer using SAW filters for handheld phones

A hybrid integrated circuit is provided having a substrate with at least one active and passive element disposed thereon. A lead frame has a plurality of leads and a support plate. The support plate supports the substrate. The support plate and inner leads are encapsulated in a resin mold package. An opening is formed in the support plate to thermally connect the bottom surface of the substrate to the resin mold package, and a plurality of devoid portions are formed in the substrate causing the amount of edge area contacting the resin mold package to be increased and adhesion between the substrate and the resin mold package improved.

Resin mold package structure of integrated circuit

This invention is a duplexer device comprising two surface acoustic wave filters having band center frequencies different from each other and a line pattern for matching phases of the two surface acoustic Wave filters, wherein provided are: a wire bonding pad layer having a plurality of pads including. pads. for connecting the line pattern with terminals on the surface acoustic wave filters and pads for connecting a common terminal connected to. an external antenna with the line pattern; and a first pad connecting one of the surface acoustic wave filters and a first end of the line pattern and a second pad connecting the common terminal and a second end of the line pattern being arranged at positions that are the most distant from each other inside the wire bonding pad layer.

Nobuo Hirasawa

Papers

Surface acoustic wave filter duplexer comprising a multi-layer package and phase matching patterns

A design of antenna duplexer using ladder type SAW filters

Development of small antenna duplexer using SAW filters for handheld phones

Resin mold package structure of integrated circuit

Saw filter duplexer device with optimal location of a phase matching line pattern and wire bonding pads