Patents by Inventor Bradley Paul Barber
Bradley Paul Barber has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Publication number: 20080101263Abstract: According to an exemplary embodiment, a duplexer includes a single-ended to differential filter, where the single-ended to differential filter includes a ladder stage coupled to an antenna port of the duplexer. The single-ended to differential filter further includes a balun stage coupled to the ladder stage. The single-ended to differential filter further includes a lattice stage coupled to the balun stage, where the balun stage is configured to provide single-ended to differential signal conversion between the ladder stage and the lattice stage. The lattice stage can be coupled to differential receive ports of the duplexer. The duplexer can further include a single-ended to single-ended filter coupled between the antenna port and a transmit port of the duplexer.Type: ApplicationFiled: May 10, 2007Publication date: May 1, 2008Inventors: Bradley Paul Barber, Hao Zhang
-
Patent number: 7328497Abstract: 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.Type: GrantFiled: June 6, 2005Date of Patent: February 12, 2008Assignee: Agere Systems Inc.Inventors: Bradley Paul Barber, Yiu-Huen Wong
-
Patent number: 7296329Abstract: 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.Type: GrantFiled: February 4, 2000Date of Patent: November 20, 2007Assignee: Agere Systems Inc.Inventors: Bradley Paul Barber, Linus Albert Fetter, Michael George Zierdt
-
Patent number: 6890445Abstract: 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.Type: GrantFiled: December 13, 2001Date of Patent: May 10, 2005Assignee: Agere Systems, Inc.Inventors: Bradley Paul Barber, LaRue Norman Dunkleberger, Jason Paul Goodelle, Thomas Herbert Shilling
-
Patent number: 6746577Abstract: 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.Type: GrantFiled: December 16, 1999Date of Patent: June 8, 2004Assignee: Agere Systems, Inc.Inventors: Bradley Paul Barber, Linus Albert Fetter
-
Patent number: 6674291Abstract: 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.Type: GrantFiled: September 26, 2000Date of Patent: January 6, 2004Assignee: Agere Systems Guardian Corp.Inventors: Bradley Paul Barber, Peter Ledel Gammel, Juan A. Herbsommer, Hugo F. Safar, Yiu-Huen Wong
-
Patent number: 6657517Abstract: 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.Type: GrantFiled: December 20, 2001Date of Patent: December 2, 2003Assignee: Agere Systems, Inc.Inventors: Bradley Paul Barber, Peter Ledel Gammel, LaRue Norman Dunkleberger
-
Patent number: 6635519Abstract: 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.Type: GrantFiled: January 10, 2002Date of Patent: October 21, 2003Assignee: Agere Systems, Inc.Inventors: Bradley Paul Barber, Peter Ledel Gammel, Yiu-Huen Wong
-
Patent number: 6601276Abstract: 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.Type: GrantFiled: May 11, 2001Date of Patent: August 5, 2003Assignee: Agere Systems Inc.Inventor: Bradley Paul Barber
-
Patent number: 6603241Abstract: 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 SiO2 and/or sputter deposited SiO2 is applied as topmost layer in the reflector stack/acoustic mirror arrangement of the device.Type: GrantFiled: May 23, 2000Date of Patent: August 5, 2003Assignee: Agere Systems, Inc.Inventors: Bradley Paul Barber, Harold Alexis Huggins, Ronald Eugene Miller, Donald Winslow Murphy, Yiu-Huen Wong
-
Publication number: 20030129785Abstract: 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.Type: ApplicationFiled: January 10, 2002Publication date: July 10, 2003Inventors: Bradley Paul Barber, Peter Ledel Gammel, Yiu-Huen Wong
-
Patent number: 6587212Abstract: 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.Type: GrantFiled: October 31, 2000Date of Patent: July 1, 2003Assignee: Agere Systems Inc.Inventors: Bradley Paul Barber, Peter Ledel Gammel, John Edwin Graebner
-
Publication number: 20030117236Abstract: 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.Type: ApplicationFiled: December 20, 2001Publication date: June 26, 2003Inventors: Bradley Paul Barber, Peter Ledel Gammel, LaRue Norman Dunkleberger
-
Publication number: 20030111437Abstract: 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.Type: ApplicationFiled: December 13, 2001Publication date: June 19, 2003Inventors: Bradley Paul Barber, LaRue Norman Dunkleberger, Jason Paul Goodelle, Thomas Herbert Shilling
-
Publication number: 20020185936Abstract: 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.Type: ApplicationFiled: July 10, 2002Publication date: December 12, 2002Inventors: Bradley Paul Barber, Yiu-Huen Wong
-
Patent number: 6486751Abstract: Improved bandwidths and oscillation uniformity is obtained through a rod type BAW TFR structure formed over a semiconductor support. The resonator includes a first and a second electrode and a plurality of distinct elemental piezoelectric structures between the electrodes. Each of the piezoelectric structures has a length, a width and a height, the height being the distance between the electrodes. The height of the piezoelectric structures is at least equal to or more than one of the length or the width, or both. Such resonator is made by forming on a common bottom a plurality of distinct piezoelectric structures each having a length, a width and a height, wherein the height is formed at least equal to the width or the length of the piezoelectric structure, and forming a common top electrode thereover.Type: GrantFiled: September 26, 2000Date of Patent: November 26, 2002Assignee: Agere Systems Inc.Inventors: Bradley Paul Barber, Edward Chan, John Edwin Graebner
-
Publication number: 20020166218Abstract: 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.Type: ApplicationFiled: May 11, 2001Publication date: November 14, 2002Inventor: Bradley Paul Barber
-
Publication number: 20020115230Abstract: 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.Type: ApplicationFiled: February 12, 2001Publication date: August 22, 2002Inventors: Bradley Paul Barber, Linus Albert Fetter, Harold Alexis Huggins, Ronald Eugene Miller
-
Patent number: 6437667Abstract: The present invention provides a method for tuning a thin film resonator (TFR) filter comprising a plurality of TFR components formed on a substrate. Each of the TFR components has a set of resonant frequencies that depend on material parameters and construction. TFR bandpass filter response for example can be produced by shifting the set of resonant frequencies in at least one of the series branch TFR components so as to establish the desired shape of the bandpass response and the desired performance of the filter. The shifting may be advantageously performed by removing piezoelectric material from the series branch TFR component, providing a TFR filter with bandwidth and attenuation advantages over that conventionally achieved by down-shifting resonant frequency sets of the shunt TFR components by adding metal material.Type: GrantFiled: February 4, 2000Date of Patent: August 20, 2002Assignee: Agere Systems Guardian Corp.Inventors: Bradley Paul Barber, Linus Albert Fetter, George E. Rittenhouse, Michael George Zierdt
-
Patent number: 6420202Abstract: A process for configuring a thin film resonator to advantageously shape a desired acoustic mode of the resonator such that the electrical and acoustic performance of the resonator is enhanced. As a result of the contouring or shaping, a minimum amount of acoustic energy occurs near the edge of the resonator, from which energy may leak or at which undesired waves may be created by a desired mode. The process is used during batch-fabrication of thin-film resonators which are used in high frequency RF filtering or frequency control applications. Utilizing photolithography, the shaping can be achieved in a manner derived from the known methods used to manufacture lens arrays. Using the process, the lateral motion of acoustic waves within the resonator may be controlled and the acoustic energy of the sound wave positioned at a desired location within the resonator.Type: GrantFiled: May 16, 2000Date of Patent: July 16, 2002Assignee: Agere Systems Guardian Corp.Inventors: Bradley Paul Barber, Peter Ledel Gammel, Harold A. Huggins, Yiu-Huen Wong