Disclosed is an acoustic resonator that includes a substrate, a first electrode, a layer of piezoelectric material, a second electrode, and an alternating frame region. The first electrode is adjacent the substrate, and the first electrode has an outer perimeter. The piezoelectric layer is adjacent the first electrode. The second electrode is adjacent the piezoelectric layer and the second electrode has an outer perimeter. The alternating frame region is on one of the first and second electrodes.

Acoustic resonator performance enhancement using alternating frame structure

A filter formed of acoustic resonators, where each resonator has its own cavity and a bottom electrode that spans the entirety of the cavity, so that the bottom electrode has an unsupported interior region surrounded by supported peripheral regions. In the preferred embodiment, the cavity is formed by etching a depression into the substrate, filling the depression with a sacrificial material, depositing the piezoelectric and electrode layers that define an FBAR or SBAR, and then removing the sacrificial material from the depression. Also in the preferred embodiment, the sacrificial material is removed via release holes that are limited to the periphery of the depression. Preferably, the bottom electrode is the only electrode that spans the cavity, thereby limiting the formation of parasitic FBARs or SBARs. In one embodiment, the bottom electrode includes a serpentine edge that leaves a portion of one side of the cavity free of overlap by the bottom electrode, so that a top electrode may overlap this portion. Thus, the top and bottom electrodes can overlap the same side without sandwiching the piezoelectric layer outside of the unsupported interior region.

Cavity spanning bottom electrode of a substrate-mounted bulk wave acoustic resonator

Film bulk acoustic resonators (FBARs) having frame elements and filters including the resonators are described.

Piezoelectric resonator structures and electrical filters having frame elements

An acoustic resonator comprises a first electrode a second electrode and a piezoelectric layer disposed between the first and second electrodes. The acoustic resonator further comprises a reflective element disposed beneath the first electrode, the second electrode and the piezoelectric layer. An overlap of the reflective element, the first electrode, the second electrode and the piezoelectric layer comprises an active area of the acoustic resonator. The acoustic resonator also comprises a bridge adjacent to a termination of the active area of the acoustic resonator.

Acoustic resonator structure comprising a bridge

A leadframe-based semiconductor package is proposed for the packaging of a semiconductor device, such as a multi-media card (MMC) chipset. The proposed semiconductor package is characterized by the use of a leadframe, rather than BT substrate or film, as the chip carrier for MMC chipset. The leadframe includes a supporting bar, a chip-supporting structure arranged at a downset position in relation to the supporting bar; and a plurality of leads, each lead including an outer-lead portion and an inner-lead portion; wherein the outer-lead portion is levelly linked to the supporting bar, while the inner-lead portion is arranged beside the chip-supporting structure and linked to the outer-lead portion via an intermediate-lead portion. The leadframe can be either the type having die pad or the type having no die pad. In the case of the type having die pad, a semiconductor chip is mounted on the die pad; and in the case of the type having no die pad, one or more semiconductor chips are mounted over an elongated part of the inner-lead portions of the leads. The use of leadframe allows the MMC package to be manufactured without having to include a lidding process, so that the MMC manufacture can be carried out in a less complex and more cost-effective manner.

Leadframe-based semiconductor package for multi-media card

Free Convection Heat Transfer Coefficients From Rectangular Vertical Fins

A temperature compensated resonator (15) and method for making the temperature compensated resonator (15) The temperature compensated resonator (15) has a substrate (110) including a cavity (120, 160) and a resonator layer (150) A bonding medium (159, 160) couples the substrate (110) to the resonator layer (150) The resonator layer (150) is bonded atop the cavity (120, 160) A conductor (215) is included on the resonator layer (150) The conductor (215) heats the resonator layer (150) in response to a current passing through the conductor (215)

Temperature compensated resonator and method

A cooling system is described which is appropriate to many high performance missiles. The invention comprises heat pipe/thermal diode devices, and a heat storage medium. Heat generated by electronic components of a missile is either conducted to the skin of the missile to be dissipated or is stored internally for later dissipation.

Passive, recyclable cooling system for missile electronics

a semiconductor die having bump type contact areas thereon with film strip leads bonded thereto and fired glass encapsulating only the active side of the die and the bump contact areas. The method of encapsulation includes bonding the film strip leads to the bumps of the die, coating the bumps and active area with unfired glass and firing the glass at a temperature generally below 450° C. The method also includes bonding the film strip leads to the bumps and firing the glass simultaneously or firing the glass and remelting glass covering the bumps to bond the leads to the bumps through the fired glass.

Hermetic glass encapsulation for semiconductor die and method

A converging/diverging venturi assembly positioned in a subsonic fluid flow stream for producing a supersonic flow velocity in the downstream diverging section with a pressure pickoff system that is located adjacent a minimum static pressure location just prior to a point where shock waves begin to form. The low pressure in the supersonic region in front of the shock wave may be utilized for reducing the boiling temperature of a fluid in a boiler by porting a tube from the low pressure venturi to the boiler, thus improving the heat transfer characteristics of the boiler where the boiler is used for a heat sink for heat sources in a mobile vehicle.

John R. Welling

Papers

Free Convection Heat Transfer Coefficients From Rectangular Vertical Fins

Temperature compensated resonator and method

Passive, recyclable cooling system for missile electronics

Hermetic glass encapsulation for semiconductor die and method

Water boiler/venturi cooler