Agere Systems Inc.

Agere Systems Guardian Corp.

Lucent Technologies Inc.

At+t Corp.

Bradley Paul Barber

Peter Ledel Gammel

David John Bishop

Yiu-Huen Wong

Linus Albert Fetter

Harold Alexis Huggins

Ronald Eugene Miller

Vladimir Anatolyevich Aksyuk

Michael George Zierdt

Clinton R Giles

Lawrence Warren Stulz

Rene R Ruel

Hugo Fernando Safar

John Edwin Graebner

C Randy Giles

LaRue Norman Dunkleberger

Juan Alejandro Herbsommer

Nicholas J Frigo

Donald Winslow Murphy

Thomas Herbert Shilling

George Endicott Rittenhouse

Rafael Nathan Kleiman

Nathan R Belk

Victor M Lubecke

Edward Chan

Jason Paul Goodelle

Matthew A Marcus

Vladimir J Aksyuk

A method of isolating piezoelectric thin film acoustic resonator devices to prevent laterally propagating waves generated by the device from leaving the device and/or interfering with adjacent devices or systems. Specifically, this isolation technique involves the manipulation or isolation of the piezoelectric material layer between the acoustic resonator devices, in an effort to limit the amount of acoustic energy which propagates in a lateral direction away from the device. In one aspect, at least a portion of the piezoelectric material not involved in signal transmission by transduction between RF and acoustic energy is removed from the device. In another aspect, the growth a piezoelectric material is limited to certain regions during fabrication of the device. In a further aspect, the crystal orientation of the piezoelectric material is disrupted or altered during device fabrication so as to form regions having excellent piezoelectric properties and regions exhibiting poor piezoelectric characteristics.

Method of isolation for acoustic resonator device

Forming a thin film acoustic device by patterning a layer of non-conducting material on a first side of a substrate to expose a portion of the first substrate side; depositing layers of conducting material on the layer of non-conducting material and the exposed portion of the first substrate side; depositing a layer of piezoelectric material on the layers of conducting material; depositing and patterning additional layers of material on the layer of piezoelectric material to form a first device electrode; depositing and patterning a masking layer on a second side of the substrate to expose a portion of the second substrate side; etching away the exposed substrate portion to expose the patterned layer of non-conducting material and a portion of the layers of conducting material; and etching away the exposed portion of the layers of conducting material to form a second device electrode.

Methods of fabricating a membrane with improved mechanical integrity

Methods for fabricating robust films across a patterned underlying layer's edges or steps are disclosed. The novel methods diminish the negative effects of electrode steps or edges on the integrity of a membrane. Thus, the methods are particularly applicable to membrane release technology. The height of the step or edge is eliminated or reduced to increase the mechanical integrity of the film.

The present invention is a method for adjusting the resonant frequency of a mechanical resonator whose frequency is dependent on the overall resonator thickness. Alternating selective etching is used to remove distinct adjustment layers from a top electrode. One of the electrodes is structured with a plurality of stacked adjustment layers, each of which has distinct etching properties from any adjacent adjustment layers. Also as part of the same invention is a resonator structure in which at least one electrode has a plurality of stacked layers of a material having different etching properties from any adjacent adjustment layers, and each layer has a thickness corresponding to a calculated frequency increment in the resonant frequency of the resonator.

Incremental tuning process for electrical resonators based on mechanical motion

A method is provided for adjusting the resonant frequency of a mechanical resonator whose frequency is dependent on the overall resonator thickness. Alternating selective etching is used to remove distinct adjustment layers from a top electrode. One of the electrodes is structured with a plurality of stacked adjustment layers, each of which has distinct etching properties from any adjacent adjustment layers. Also as part of the same invention is a resonator structure in which at least one electrode has a plurality of stacked layers of a material having different etching properties from any adjacent adjustment layers, and each layer has a thickness corresponding to a calculated frequency increment in the resonant frequency of the resonator.

In the method, a cap wafer surface is lithographically etched at time of fabrication, so that a raised ridge onto which bonding material is placed is formed near a perimeter of a desired cavity region. This is done in order to reduce the bonding area between the cap wafer and electronic device wafers, so as to provide a better defined standoff. In another aspect of the method, the cap wager surface is lithographically etched to form recesses or trenches near the perimeter of a cavity region, each recess being filled with a sealing material, and polished if necessary to be flush with the cap wafer surface. Thereafter, the cap wafer surface is etched so that the filled recesses become the raised ridges which are used to bond a cap wafer to an electronic device wafer.

Process for packaging electronic devices using thin bonding regions

The invention embodies a method and apparatus for controlling the thickness of a dielectric film formed by physical vapor deposition (PVD). The method compensates for the continuously varying electrical load conditions inherent in dielectric deposition via PVD. The method can be implemented through three different stages. Initially, the system power supply can be configured to operate in either constant current or constant voltage mode, herein referred to as constant supply parameter mode. Next, a gas composition which minimizes excursions in system impedance under these conditions is empirically determined. Finally, a test deposition can be performed using the constant parameter power supply mode and the gas mixture. This deposition is performed while tracking and summing the energy delivered to the system. The thickness of the deposited film is subsequently measured, and from these data a thickness-per-unit-energy relationship is determined. Depositions of predictable film thickness are then reproducibly performed under these established conditions. In practice, a given deposition is terminated at a value of total energy as determined by the established thickness per unit energy value and the required film thickness. The method is much more reliable than the current art technique of deposition at constant power for a fixed time.

Method and apparatus for thickness control and reproducibility of dielectric film deposition

The effects of electromigration have been shown to lead to damage of metal electrodes of electronic devices such as thin film resonator (TFR) devices in only a few hours, for a test input power that is within the operational range of these devices. It has been determined that this failure is sensitive to the frequency of the input power. The present invention provides a method and apparatus for determining high power reliability in electronic devices, so as to enable an accurate determination of the failure time of the electronic device, and hence projected lifetime. This determination is independent from the frequency of an input power applied to the electronic device as part of the method for testing the device. Based on the above results, a TFR device has been developed, which includes a protective or electromigration-reducing layer such as titanium being deposited atop an electrode of the device. The TFR device with the modified electrode structure can operate at higher power levels and has a longer operational lifetime than what is currently available.

Method and apparatus for determining and/or improving high power reliability in thin film resonator devices, and a thin film resonator device resultant therefrom

Differing metallic electrodes having the same or differing thickness are formed at different locations on a support structure and/or on a single thickness film of piezoelectric material in order to form a multiple frequency resonator device having greatly separated acoustic resonance frequencies. A plurality of multiple frequency resonators can be combined to form a blank of frequency selective devices in order to handle the many different RF bands, at widely varying frequencies, that wireless communication technologies demand today.

Multi-frequency thin film resonators

In the thin film resonator, a piezoelectric membrane is disposed over a substrate. A first support structure defines a space over the substrate and supports the edges of the piezoelectric membrane such that the piezoelectric membrane is disposed over this space. A further support structure is disposed within the space to the piezoelectric membrane.

Structurally supported thin film resonator and method of fabrication

A reflector stack or acoustic mirror arrangement for an acoustic device is described which may attain the highest possible impedance mismatch between alternating higher and lower impedance reflecting layers of the stack, so as to maximize bandwidth. The arrangement may also reduce manufacturing costs by requiring fewer layers for the device, as compared to conventional acoustic mirrors. The thinner reflecting stack is accordingly fabricated in reduced time to lower cost, by incorporating materials providing a larger acoustic impedance mismatch than those currently obtainable. The bandwidth of the resulting acoustic resonator device may be widened, particularly when a low density material such as aerogel, CVD SiO and/or sputter deposited SiO is applied as topmost layer in the reflector stack/acoustic mirror arrangement of the device.

Acoustic mirror materials for acoustic devices

The invention relates to manufacturing electromechanical resonators for use in electromechanical filters. Such filters require resonators having different resonant frequencies. Typically all resonators are manufactured having the same resonant frequency and the resonant frequency of selected resonators is altered by the deposition of additional material on selected resonators in the form of additional layers. According to this invention, these layers are formed coextensive with the underlying layers of the resonator by first patterning larger areas of the added material, then masking the patterned areas with masks smaller than the patterned areas and etching both the underlying layer and the patterned area without moving the mask.

Method for self alignment of patterned layers in thin film acoustic devices

A method for studying vibrational modes of an electro-acoustic device includes driving the electro-acoustic device to produce at least one vibrational mode therein, collecting phase and amplitude data from the electro-acoustic device using optical interferometry, and mapping the at least one vibrational mode based upon the collected phase and amplitude data. The phase and amplitude data may be processed to provide an instantaneous three-dimensional view of the at least one vibrational mode. Furthermore, a sequence of instantaneous three-dimensional views may be constructed to form a motion picture of the at least one vibrational mode. Additionally, collecting may include raster scanning to provide phase and amplitude data across a surface of the electro-acoustic device.

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Chatham, NJ, United States of America

Bradley Paul Barber