Patents by Inventor Ramakrishna Vetury

Ramakrishna Vetury 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).

  • Patent number: 11881831
    Abstract: A method of manufacture for an acoustic resonator device. The method includes forming a nucleation layer characterized by nucleation growth parameters overlying a substrate and forming a strained piezoelectric layer overlying the nucleation layer. The strained piezoelectric layer is characterized by a strain condition and piezoelectric layer parameters. The process of forming the strained piezoelectric layer can include an epitaxial growth process configured by nucleation growth parameters and piezoelectric layer parameters to modulate the strain condition in the strained piezoelectric layer. By modulating the strain condition, the piezoelectric properties of the resulting piezoelectric layer can be adjusted and improved for specific applications.
    Type: Grant
    Filed: January 29, 2020
    Date of Patent: January 23, 2024
    Assignee: Akoustis, Inc.
    Inventors: Shawn R. Gibb, Alexander Y. Feldman, Mark D. Boomgarden, Michael P. Lewis, Ramakrishna Vetury, Jeffrey B. Shealy
  • Publication number: 20230344399
    Abstract: A method of manufacture for an acoustic resonator or filter device. In an example, the present method can include forming metal electrodes with different geometric areas and profile shapes coupled to a piezoelectric layer overlying a substrate. These metal electrodes can also be formed within cavities of the piezoelectric layer or the substrate with varying geometric areas. Combined with specific dimensional ratios and ion implantations, such techniques can increase device performance metrics. In an example, the present method can include forming various types of perimeter structures surrounding the metal electrodes, which can be on top or bottom of the piezoelectric layer. These perimeter structures can use various combinations of modifications to shape, material, and continuity. These perimeter structures can also be combined with sandbar structures, piezoelectric layer cavities, the geometric variations previously discussed to improve device performance metrics.
    Type: Application
    Filed: June 27, 2023
    Publication date: October 26, 2023
    Inventors: Ramakrishna VETURY, Alexander Y. Feldman, Michael D. Hodge, Art Geiss, Shawn R. Gibb, Mark D. Boomgarden, Michael P. Lewis, Pinal Patel, Jeffrey B. Shealy
  • Publication number: 20230336139
    Abstract: An RF filter system includes a plurality of bulk acoustic wave resonators arranged in a circuit having serial and parallel shunt configurations of resonators. Each resonator having a reflector, a support member including a surface, a first electrode including tungsten, overlying the reflector, a piezoelectric film including crystalline aluminum scandium nitride overlapping the first electrode, a second electrode including tungsten overlapping the piezoelectric film and the first electrode, and a passivation layer including silicon nitride overlying the second electrode. Portions of the support member surface of at least one resonator define a cavity region having a portion of the first electrode of the at least one resonator is located within the cavity region. The pass band circuit response has a bandwidth corresponding to a thickness of at least one of the first electrode, piezoelectric film, second electrode, and passivation layer. The system can include single crystal or polycrystalline BAW resonators.
    Type: Application
    Filed: June 23, 2023
    Publication date: October 19, 2023
    Inventors: Dae Ho KIM, Mary WINTERS, Ramakrishna VETURY, Jeffrey B. SHEALY
  • Publication number: 20230291376
    Abstract: A method and structure for a transfer process for an acoustic resonator device. In an example, a bulk acoustic wave resonator (BAWR) with an air reflection cavity is formed. A piezoelectric thin film is grown on a crystalline substrate. A first patterned electrode is deposited on the surface of the piezoelectric film. An etched sacrificial layer is deposited over the first electrode and a planarized support layer is deposited over the sacrificial layer, which is then bonded to a substrate wafer. The crystalline substrate is removed and a second patterned electrode is deposited over a second surface of the film. The sacrificial layer is etched to release the air reflection cavity. Also, a cavity can instead be etched into the support layer prior to bonding with the substrate wafer. Alternatively, a reflector structure can be deposited on the first electrode, replacing the cavity.
    Type: Application
    Filed: May 22, 2023
    Publication date: September 14, 2023
    Inventors: Dae Ho KIM, Mary WINTERS, Ramakrishna VETURY, Jeffrey B. SHEALY
  • Patent number: 11728781
    Abstract: A method of manufacture for an acoustic resonator or filter device. In an example, the present method can include forming metal electrodes with different geometric areas and profile shapes coupled to a piezoelectric layer overlying a substrate. These metal electrodes can also be formed within cavities of the piezoelectric layer or the substrate with varying geometric areas. Combined with specific dimensional ratios and ion implantations, such techniques can increase device performance metrics. In an example, the present method can include forming various types of perimeter structures surrounding the metal electrodes, which can be on top or bottom of the piezoelectric layer. These perimeter structures can use various combinations of modifications to shape, material, and continuity. These perimeter structures can also be combined with sandbar structures, piezoelectric layer cavities, the geometric variations previously discussed to improve device performance metrics.
    Type: Grant
    Filed: September 30, 2021
    Date of Patent: August 15, 2023
    Assignee: Akoustis, Inc.
    Inventors: Ramakrishna Vetury, Alexander Y. Feldman, Michael D. Hodge, Art Geiss, Shawn R. Gibb, Mark D. Boomgarden, Michael P. Lewis, Pinal Patel, Jeffrey B. Shealy
  • Publication number: 20230253943
    Abstract: A bulk acoustic wave (BAW) resonator includes a solidly mounted reflector, for example, a Bragg-type reflector, a piezoelectric layer, and first and second electrodes on first and second surfaces, respectively, of the piezoelectric layer. A filter device or filter system includes at least one BAW resonator. Related methods of fabrication include forming the BAW resonator.
    Type: Application
    Filed: April 19, 2023
    Publication date: August 10, 2023
    Inventors: Dae Ho KIM, Mary Winters, Ramakrishna Vetury, Jeffrey B. Shealy
  • Patent number: 11711064
    Abstract: An RF filter system includes a plurality of bulk acoustic wave resonators arranged in a circuit having serial and parallel shunt configurations of resonators. Each resonator having a reflector, a support member including a surface, a first electrode including tungsten, overlying the reflector, a piezoelectric film including crystalline aluminum scandium nitride overlapping the first electrode, a second electrode including tungsten overlapping the piezoelectric film and the first electrode, and a passivation layer including silicon nitride overlying the second electrode. Portions of the support member surface of at least one resonator define a cavity region having a portion of the first electrode of the at least one resonator is located within the cavity region. The pass band circuit response has a bandwidth corresponding to a thickness of at least one of the first electrode, piezoelectric film, second electrode, and passivation layer. The system can include single crystal or polycrystalline BAW resonators.
    Type: Grant
    Filed: September 14, 2022
    Date of Patent: July 25, 2023
    Assignee: Akoustis, Inc.
    Inventors: Dae Ho Kim, Mary Winters, Ramakrishna Vetury, Jeffrey B. Shealy
  • Patent number: 11671067
    Abstract: A method and structure for a transfer process for an acoustic resonator device. In an example, a bulk acoustic wave resonator (BAWR) with an air reflection cavity is formed. A piezoelectric thin film is grown on a crystalline substrate. A first patterned electrode is deposited on the surface of the piezoelectric film. An etched sacrificial layer is deposited over the first electrode and a planarized support layer is deposited over the sacrificial layer, which is then bonded to a substrate wafer. The crystalline substrate is removed and a second patterned electrode is deposited over a second surface of the film. The sacrificial layer is etched to release the air reflection cavity. Also, a cavity can instead be etched into the support layer prior to bonding with the substrate wafer. Alternatively, a reflector structure can be deposited on the first electrode, replacing the cavity.
    Type: Grant
    Filed: March 18, 2020
    Date of Patent: June 6, 2023
    Assignee: Akoustis, Inc.
    Inventors: Dae Ho Kim, Mary Winters, Ramakrishna Vetury, Jeffrey B. Shealy
  • Patent number: 11646719
    Abstract: An RF filter system including a plurality of BAW resonators arranged in a circuit, the circuit including a serial configuration of resonators and a parallel shunt configuration of resonators, the circuit having a circuit response corresponding to the serial configuration and the parallel configuration of the plurality of bulk acoustic wave resonators including a transmission loss from a pass band having a bandwidth from 5.170 GHz to 5.835 GHz. Resonators include a support member with a multilayer reflector structure; a first electrode including tungsten; a piezoelectric film including aluminum scandium nitride; a second electrode including tungsten; and a passivation layer including silicon nitride. At least one resonator includes at least a portion of the first electrode located within a cavity region defined by a surface of the support member.
    Type: Grant
    Filed: August 11, 2022
    Date of Patent: May 9, 2023
    Assignee: AKOUSTIS, INC.
    Inventors: Jeffrey B. Shealy, Michael Hodge, Rohan W. Houlden, Shawn R. Gibb, Mary Winters, Ramakrishna Vetury, David M. Aichele
  • Patent number: 11646717
    Abstract: An RF filter system including a plurality of BAW resonators arranged in a circuit, the circuit including a serial configuration of resonators and a parallel shunt configuration of resonators, the circuit having a circuit response corresponding to the serial configuration and the parallel configuration of the plurality of bulk acoustic wave resonators including a transmission loss from a pass band having a bandwidth from 5.170 GHz to 5.330 GHz. Resonators include a support member with a multilayer reflector structure; a first electrode including tungsten; a piezoelectric film including aluminum scandium nitride; a second electrode including tungsten; and a passivation layer including silicon nitride. At least one resonator includes at least a portion of the first electrode located within a cavity region defined by a surface of the support member.
    Type: Grant
    Filed: August 15, 2022
    Date of Patent: May 9, 2023
    Assignee: Akoustis, Inc.
    Inventors: Jeffrey B. Shealy, Michael D. Hodge, Rohan W. Houlden, Shawn R. Gibb, Mary Winters, Ramakrishna Vetury, David M. Aichele
  • Patent number: 11646718
    Abstract: An RF filter system including a plurality of BAW resonators arranged in a circuit, the circuit including a serial configuration of resonators and a parallel shunt configuration of resonators, the circuit having a circuit response corresponding to the serial configuration and the parallel configuration of the plurality of bulk acoustic wave resonators including a transmission loss from a pass band having a bandwidth from 5.855 GHz to 5.925 GHz. Resonators include a support member with a multilayer reflector structure; a first electrode including tungsten; a piezoelectric film including aluminum scandium nitride; a second electrode including tungsten; and a passivation layer including silicon nitride. At least one resonator includes at least a portion of the first electrode located within a cavity region defined by a surface of the support member.
    Type: Grant
    Filed: August 17, 2022
    Date of Patent: May 9, 2023
    Assignee: Akoustis, Inc.
    Inventors: Jeffrey B. Shealy, Michael D. Hodge, Rohan W. Houlden, Shawn R. Gibb, Mary Winters, Ramakrishna Vetury, David M. Aichele
  • Patent number: 11646710
    Abstract: A bulk acoustic wave (BAW) resonator includes a solidly mounted reflector, for example, a Bragg-type reflector, a piezoelectric layer, and first and second electrodes on first and second surfaces, respectively, of the piezoelectric layer. A filter device or filter system includes at least one BAW resonator. Related methods of fabrication include forming the BAW resonator.
    Type: Grant
    Filed: July 14, 2022
    Date of Patent: May 9, 2023
    Assignee: Akoustis, Inc.
    Inventors: Dae Ho Kim, Mary Winters, Ramakrishna Vetury, Jeffrey B. Shealy
  • Patent number: 11637545
    Abstract: An RF filter system including a plurality of BAW resonators arranged in a circuit, the circuit including a serial configuration of resonators and a parallel shunt configuration of resonators, the circuit having a circuit response corresponding to the serial configuration and the parallel configuration of the plurality of bulk acoustic wave resonators including a transmission loss from a pass band having a bandwidth from 5.490 GHz to 5.835 GHz. Resonators include a support member with a multilayer reflector structure; a first electrode including tungsten; a piezoelectric film including aluminum scandium nitride; a second electrode including tungsten; and a passivation layer including silicon nitride. At least one resonator includes at least a portion of the first electrode located within a cavity region defined by a surface of the support member.
    Type: Grant
    Filed: August 11, 2022
    Date of Patent: April 25, 2023
    Assignee: AKOUSTIS, INC.
    Inventors: Jeffrey B. Shealy, Michael Hodge, Rohan W. Houlden, Shawn R. Gibb, Mary Winters, Ramakrishna Vetury, David M. Aichele
  • Publication number: 20230114606
    Abstract: A system for a wireless communication infrastructure using single crystal devices. The wireless system can include a controller coupled to a power source, a signal processing module, and a plurality of transceiver modules. Each of the transceiver modules includes a transmit module configured on a transmit path and a receive module configured on a receive path. The transmit modules each include at least a transmit filter having one or more filter devices, while the receive modules each include at least a receive filter. Each of these filter devices includes a single crystal acoustic resonator device formed with a thin film transfer process with at least a first electrode material, a single crystal material, and a second electrode material. Wireless infrastructures using the present single crystal technology perform better in high power density applications, enable higher out of band rejection (OOBR), and achieve higher linearity as well.
    Type: Application
    Filed: December 7, 2022
    Publication date: April 13, 2023
    Inventors: Ramakrishna VETURY, Jeffrey B. Shealy
  • Patent number: 11616490
    Abstract: An RF circuit device using modified lattice, lattice, and ladder circuit topologies. The devices can include four resonator devices and four shunt resonator devices. In the ladder topology, the resonator devices are connected in series from an input port to an output port while shunt resonator devices are coupled the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a pair of resonator devices that are coupled to differential input and output ports. A pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. These topologies may be applied using single crystal or polycrystalline bulk acoustic wave (BAW) resonators.
    Type: Grant
    Filed: July 6, 2022
    Date of Patent: March 28, 2023
    Assignee: Akoustis, Inc.
    Inventors: Dae Ho Kim, Mary Winters, Ramakrishna Vetury, Jeffrey B. Shealy, Rohan W. Houlden, David M. Aichele
  • Patent number: 11581306
    Abstract: A method of manufacture and structure for a monolithic single chip single crystal device. The method can include forming a first single crystal epitaxial layer overlying the substrate and forming one or more second single crystal epitaxial layers overlying the first single crystal epitaxial layer. The first single crystal epitaxial layer and the one or more second single crystal epitaxial layers can be processed to form one or more active or passive device components. Through this process, the resulting device includes a monolithic epitaxial stack integrating multiple circuit functions.
    Type: Grant
    Filed: February 19, 2021
    Date of Patent: February 14, 2023
    Assignee: Akoustis, Inc.
    Inventors: Shawn R. Gibb, David Aichele, Ramakrishna Vetury, Mark D. Boomgarden, Jeffrey B. Shealy
  • Patent number: 11563412
    Abstract: A method of manufacture for an acoustic resonator or filter device. In an example, the present method can include forming metal electrodes with different geometric areas and profile shapes coupled to a piezoelectric layer overlying a substrate. These metal electrodes can also be formed within cavities of the piezoelectric layer or the substrate with varying geometric areas. Combined with specific dimensional ratios and ion implantations, such techniques can increase device performance metrics. In an example, the present method can include forming various types of perimeter structures surrounding the metal electrodes, which can be on top or bottom of the piezoelectric layer. These perimeter structures can use various combinations of modifications to shape, material, and continuity. These perimeter structures can also be combined with sandbar structures, piezoelectric layer cavities, the geometric variations previously discussed to improve device performance metrics.
    Type: Grant
    Filed: February 9, 2021
    Date of Patent: January 24, 2023
    Assignee: Akoustis, Inc.
    Inventors: Ramakrishna Vetury, Alexander Y. Feldman, Michael D. Hodge, Art Geiss, Shawn R. Gibb, Mark D. Boomgarden, Michael P. Lewis, Pinal Patel, Jeffrey B. Shealy
  • Patent number: 11558023
    Abstract: A method of manufacture for an acoustic resonator or filter device. In an example, the present method can include forming metal electrodes with different geometric areas and profile shapes coupled to a piezoelectric layer overlying a substrate. These metal electrodes can also be formed within cavities of the piezoelectric layer or the substrate with varying geometric areas. Combined with specific dimensional ratios and ion implantations, such techniques can increase device performance metrics. In an example, the present method can include forming various types of perimeter structures surrounding the metal electrodes, which can be on top or bottom of the piezoelectric layer. These perimeter structures can use various combinations of modifications to shape, material, and continuity. These perimeter structures can also be combined with sandbar structures, piezoelectric layer cavities, the geometric variations previously discussed to improve device performance metrics.
    Type: Grant
    Filed: November 23, 2020
    Date of Patent: January 17, 2023
    Assignee: Akoustis, Inc.
    Inventors: Ramakrishna Vetury, Alexander Y. Feldman, Michael D. Hodge, Art Geiss, Mark D. Boomgarden, Michael P. Lewis, Pinal Patel, Dae Ho Kim, Mary Winters, Jeffrey B. Shealy
  • Publication number: 20220393668
    Abstract: An RF circuit device using modified lattice, lattice, and ladder circuit topologies. The devices can include a plurality of resonator devices and a plurality of resonator devices. In the ladder topology, the resonator devices are connected in series from an input port to an output port while shunt resonator devices are coupled the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a pair of resonator devices that are coupled to differential input and output ports. A pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. These topologies may be applied using single crystal or polycrystalline bulk acoustic wave (BAW) resonators.
    Type: Application
    Filed: August 17, 2022
    Publication date: December 8, 2022
    Inventors: Jeffrey B. SHEALY, Michael D. HODGE, Rohan W. HOULDEN, Mary WINTERS, Ramakrishna VETURY, Ya SHEN, David M. AICHELE
  • Publication number: 20220393667
    Abstract: An RF circuit device using modified lattice, lattice, and ladder circuit topologies. The devices can include a plurality of resonator devices and a plurality of resonator devices. In the ladder topology, the resonator devices are connected in series from an input port to an output port while shunt resonator devices are coupled the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a pair of resonator devices that are coupled to differential input and output ports. A pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. These topologies may be applied using single crystal or polycrystalline bulk acoustic wave (BAW) resonators.
    Type: Application
    Filed: August 15, 2022
    Publication date: December 8, 2022
    Inventors: Jeffrey B. SHEALY, Michael D. HODGE, Rohan W. HOULDEN, Mary WINTERS, Ramakrishna VETURY, Ya SHEN, David M. AICHELE