Patents by Inventor Hamid Tavassoli

Hamid Tavassoli 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: 8337660
    Abstract: A plasma reactor for processing a workpiece includes a reactor chamber, an electrostatic chuck within the chamber having a top surface for supporting a workpiece and having indentations in the top surface that form enclosed gas flow channels whenever covered by a workpiece resting on the top surface. The reactor further includes thermal control apparatus thermally coupled to the electrostatic chuck, an RF plasma bias power generator coupled to apply RF power to the electrostatic chuck, a pressurized gas supply of a thermally conductive gas, a controllable gas valve coupling the pressurized gas supply to the indentations to facilitate filling the channels with the thermally conductive gas for heat transfer between a backside of a workpiece and the electrostatic chuck at a heat transfer rate that is a function of the pressure against the backside of the workpiece of the thermally conductive gas.
    Type: Grant
    Filed: August 12, 2010
    Date of Patent: December 25, 2012
    Assignee: B/E Aerospace, Inc.
    Inventors: Douglas A. Buchberger, Jr., Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas H. Burns, Kallol Bera, Daniel J. Hoffman, Kenneth W. Cowans, William W. Cowans, Glenn W. Zubillaga, Isaac Millan
  • Patent number: 8236105
    Abstract: Apparatus for controlling the flow of a gas between a process region and an exhaust port in a semiconductor substrate processing chamber is provided. The apparatus includes at least one restrictor plate supported within the semiconductor processing chamber and at least partially circumscribing a substrate support pedestal. The restrictor plate is adapted to control the flow of at least one gas flowing between the process region and the exhaust port.
    Type: Grant
    Filed: April 8, 2004
    Date of Patent: August 7, 2012
    Assignee: Applied Materials, Inc.
    Inventors: Kallol Bera, Heeyeop Chae, Hamid Tavassoli, Yan Ye
  • Patent number: 8221580
    Abstract: A plasma reactor with a reactor chamber and an electrostatic chuck having a surface for holding a workpiece inside the chamber includes a backside gas pressure source coupled to the electrostatic chuck for applying a thermally conductive gas under a selected pressure into a workpiece-surface interface formed whenever a workpiece is held on the surface, and an evaporator inside the electrostatic chuck and a refrigeration loop having an expansion valve for controlling flow of coolant through the evaporator. The reactor further includes a temperature sensor in the electrostatic chuck, a thermal model capable of simulating heat transfer between the evaporator and the surface based upon measurements from the temperature sensor and an agile control processor coupled to the thermal model and governing the backside gas pressure source in response to predictions from the model of changes in the selected pressure that would bring the temperature measured by the sensor closer to a desired temperature.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: July 17, 2012
    Assignees: Applied Materials, Inc., BE Aerospace, Inc.
    Inventors: Douglas A. Buchberger, Jr., Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas H. Burns, Kallol Bera, Daniel J. Hoffman, Kenneth W. Cowans, William W. Cowans, Glenn W. Zubillaga, Isaac Millan
  • Publication number: 20120132397
    Abstract: Methods and systems for controlling temperatures in plasma processing chamber via pulsed application of heating power and pulsed application of cooling power. In an embodiment, temperature control is based at least in part on a feedforward control signal derived from a plasma power input into the processing chamber. In further embodiments, fluid levels in each of a hot and cold reservoir coupled to the temperature controlled component are maintained in part by a passive leveling pipe coupling the two reservoirs. In another embodiment, digital heat transfer fluid flow control valves are opened with pulse widths dependent on a heating/cooling duty cycle value and a proportioning cycle having a duration that has been found to provide good temperature control performance.
    Type: Application
    Filed: May 19, 2011
    Publication date: May 31, 2012
    Applicant: APPLIED MATERIALS, INC.
    Inventors: Fernando M. Silveira, Hamid Tavassoli, Xiaoping Zhou, Shane C. Nevil, Douglas A. Buchberger, Brad L. Mays, Tina Tsong, Chetan Mahadeswaraswamy, Yashaswini B. Pattar, Duy D. Nguyen, Walter R. Merry
  • Publication number: 20120091104
    Abstract: An electrostatic chuck assembly including a dielectric layer with a top surface to support a workpiece. A cooling channel base disposed below the dielectric layer includes a plurality of inner fluid conduits disposed beneath an inner portion of the top surface, and a plurality of outer fluid conduits disposed beneath an outer portion of the top surface. A chuck assembly includes a thermal break disposed within the cooling channel base between the inner and outer fluid conduits. A chuck assembly includes a fluid distribution plate disposed below the cooling channel base and the base plate to distribute a heat transfer fluid delivered from a common input to each inner or outer fluid conduit. The branches of the inner input manifold may have substantially equal fluid conductance.
    Type: Application
    Filed: April 6, 2011
    Publication date: April 19, 2012
    Applicant: APPLIED MATERIALS, INC.
    Inventors: Hamid Tavassoli, Surajit KUMAR, Kallol Bera, Xiaoping Zhou, Shane C. Nevil, Douglas A. Buchberger, JR.
  • Patent number: 8157951
    Abstract: A plasma reactor for processing a workpiece includes a reactor chamber, an electrostatic chuck within the chamber having a top surface for supporting a workpiece and having indentations in the top surface that form enclosed gas flow channels whenever covered by a workpiece resting on the top surface. The reactor further includes thermal control apparatus thermally coupled to the electrostatic chuck, an RF plasma bias power generator coupled to apply RF power to the electrostatic chuck, a pressurized gas supply of a thermally conductive gas, a controllable gas valve coupling the pressurized gas supply to the indentations to facilitate filling the channels with the thermally conductive gas for heat transfer between a backside of a workpiece and the electrostatic chuck at a heat transfer rate that is a function of the pressure against the backside of the workpiece of the thermally conductive gas.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: April 17, 2012
    Assignees: Applied Materials, Inc., Advanced Thermal Sciences Corporation
    Inventors: Douglas A. Buchberger, Jr., Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas H. Burns, Kallol Bera, Daniel J. Hoffman
  • Patent number: 8092639
    Abstract: A plasma reactor having a reactor chamber and an electrostatic chuck with a surface for holding a workpiece inside the chamber includes a backside gas pressure source coupled to the electrostatic chuck for applying a thermally conductive gas under a selected pressure into a workpiece-surface interface formed whenever a workpiece is held on the surface and an evaporator inside the electrostatic chuck and a refrigeration loop having an expansion valve for controlling flow of coolant through the evaporator. The reactor further includes a temperature sensor in the electrostatic chuck and a memory storing a schedule of changes in RF power or wafer temperature.
    Type: Grant
    Filed: August 12, 2010
    Date of Patent: January 10, 2012
    Assignee: Advanced Thermal Sciences Corporation
    Inventors: Douglas A. Buchberger, Jr., Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas H. Burns, Kallol Bera, Daniel J. Hoffman, Kenneth W. Cowans, William W. Cowans, Glenn W. Zubillaga, Isaac Millan
  • Patent number: 8092638
    Abstract: A plasma reactor for processing a workpiece includes a reactor chamber, an electrostatic chuck within the chamber for supporting a workpiece, an RF plasma bias power generator coupled to apply RF power to the electrostatic chuck and a refrigeration loop having an evaporator inside the electrostatic chuck with a refrigerant inlet and a refrigerant outlet. Preferably, the evaporator includes a meandering passageway distributed in a plane beneath a top surface of the electrostatic chuck. Preferably, refrigerant within the evaporator is apportioned between a vapor phase and a liquid phase. As a result, heat transfer between the electrostatic chuck and the refrigerant within the evaporator is a constant-temperature process. This feature improves uniformity of temperature distribution across a diameter of the electrostatic chuck.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: January 10, 2012
    Assignees: Applied Materials Inc., Advanced Thermal Sciences Corporation
    Inventors: Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas A. Buchberger, Jr., Douglas H. Burns, Kallol Bera, Daniel J. Hoffman
  • Publication number: 20110297650
    Abstract: A triaxial rod assembly for providing both RF power and DC voltage to a chuck assembly that supports a workpiece in a processing chamber during a manufacturing operation. In embodiments, a rod assembly includes a center conductor to be coupled to a chuck electrode for providing DC voltage to clamp a workpiece. Concentrically surrounding the center conductor is an annular RF transmission line to be coupled to an RF powered base to provide RF power to the chuck assembly. An insulator is disposed between the center conductor and RF transmission line. Concentrically surrounding the RF transmission line is a ground plane conductor coupled to a grounded base of the chuck to provide a reference voltage relative to the DC voltage. An insulator is disposed between the RF transmission line and the ground plane conductor.
    Type: Application
    Filed: April 12, 2011
    Publication date: December 8, 2011
    Applicant: APPLIED MATERIALS, INC.
    Inventors: Hamid Tavassoli, Surajit Kumar, Shane C. Nevil, Douglas A. Buchberger, JR.
  • Patent number: 8021521
    Abstract: A method of processing a workpiece in a plasma reactor having an electrostatic chuck for holding a workpiece in a chamber of the reactor includes providing a thermally conductive gas under pressure between a backside of the workpiece and a top surface of the electrostatic chuck, controlling the temperature of the electrostatic chuck, defining a desired workpiece temperature, measuring a current workpiece temperature or temperature related to the workpiece temperature and inputting the measured temperature to a thermal model representative of the electrostatic chuck. The method further includes determining from the thermal model a change in the pressure of the thermally conductive gas that would at least reduce the difference between the measured temperature and the desired temperature, and changing the pressure of the thermally conductive gas in accordance with the change determined from the thermal model.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: September 20, 2011
    Assignees: Applied Materials, Inc., Advanced Thermal Sciences Corporation
    Inventors: Douglas A. Buchberger, Jr., Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas H. Burns, Kallol Bera, Daniel J. Hoffman, Kenneth W. Cowans, Williams W. Cowans, Glenn W. Zubillaga, Isaac Millian
  • Patent number: 8012304
    Abstract: A plasma reactor having a reactor chamber and an electrostatic chuck having a surface for holding a workpiece inside the chamber includes inner and outer zone backside gas pressure sources coupled to the electrostatic chuck for applying a thermally conductive gas under respective pressures to respective inner and outer zones of a workpiece-surface interface formed whenever a workpiece is held on the surface, and inner and outer zone heat exchangers coupled to respective inner and outer zones of said electrostatic chuck. The reactor further includes inner and outer zone temperature sensors in inner and outer zones of the electrostatic chuck and a thermal model capable of simulating heat transfer through the inner and outer zones, respectively, between the evaporator and the surface based upon measurements from the inner and outer temperature sensors, respectively.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: September 6, 2011
    Assignees: Applied Materials, Inc., Advanced Thermal Sciences Corporation
    Inventors: Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas A. Buchberger, Jr., Douglas H. Burns, Kallol Bera, Daniel J. Hoffman
  • Publication number: 20110180243
    Abstract: Apparatus for controlling thermal uniformity of a substrate is provided herein. In some embodiments, the thermal uniformity of the substrate may be controlled to be more uniform. In some embodiments, the thermal uniformity of the substrate may be controlled to be non-uniform in a desired pattern. In some embodiments, an apparatus for controlling thermal uniformity of a substrate may include a substrate support having a support surface to support a substrate thereon; and a plurality of flow paths having a substantially equivalent fluid conductance disposed within the substrate support to flow a heat transfer fluid beneath the support surface.
    Type: Application
    Filed: September 20, 2010
    Publication date: July 28, 2011
    Applicant: APPLIED MATERIALS, INC.
    Inventors: KALLOL BERA, XIAOPING ZHOU, DOUGLAS A. BUCHBERGER, JR., ANDREW NGUYEN, HAMID TAVASSOLI, SURAJIT KUMAR, SHAHID RAUF
  • Publication number: 20100319851
    Abstract: A plasma reactor having a reactor chamber and an electrostatic chuck with a surface for holding a workpiece inside the chamber includes a backside gas pressure source coupled to the electrostatic chuck for applying a thermally conductive gas under a selected pressure into a workpiece-surface interface formed whenever a workpiece is held on the surface and an evaporator inside the electrostatic chuck and a refrigeration loop having an expansion valve for controlling flow of coolant through the evaporator. The reactor further includes a temperature sensor in the electrostatic chuck and a memory storing a schedule of changes in RF power or wafer temperature.
    Type: Application
    Filed: August 12, 2010
    Publication date: December 23, 2010
    Inventors: Douglas A. Buchberger, JR., Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas H. Burns, Kallol Bera, Daniel J. Hoffman
  • Publication number: 20100319852
    Abstract: A plasma reactor for processing a workpiece includes a reactor chamber, an electrostatic chuck within the chamber for supporting a workpiece, an RF plasma bias power generator coupled to apply RF power to the electrostatic chuck and a refrigeration loop having an evaporator inside the electrostatic chuck with a refrigerant inlet and a refrigerant outlet. Preferably, the evaporator includes a meandering passageway distributed in a plane beneath a top surface of the electrostatic chuck. Preferably, refrigerant within the evaporator is apportioned between a vapor phase and a liquid phase. As a result, heat transfer between the electrostatic chuck and the refrigerant within the evaporator is a constant-temperature process. This feature improves uniformity of temperature distribution across a diameter of the electrostatic chuck.
    Type: Application
    Filed: August 12, 2010
    Publication date: December 23, 2010
    Inventors: Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas A. Buchberger, JR., Douglas H. Burns, Kallol Bera, Daniel J. Hoffman
  • Publication number: 20100314046
    Abstract: A plasma reactor having a reactor chamber and an electrostatic chuck having a surface for holding a workpiece inside the chamber includes inner and outer zone backside gas pressure sources coupled to the electrostatic chuck for applying a thermally conductive gas under respective pressures to respective inner and outer zones of a workpiece-surface interface formed whenever a workpiece is held on the surface, and inner and outer evaporators inside respective inner and outer zones of the electrostatic chuck and a refrigeration loop having respective inner and cuter expansion valves for controlling flow of coolant through the inner and outer evaporators respectively. The reactor further includes inner and outer zone temperature sensors in inner and outer zones of the electrostatic chuck and a thermal model capable of simulating heat transfer through the inner and outer zones, respectively, between the evaporator and the surface based upon measurements from the inner and outer temperature sensors, respectively.
    Type: Application
    Filed: August 12, 2010
    Publication date: December 16, 2010
    Inventors: Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas A. Buchberger, JR., Douglas H. Burns, Kallol Bera, Daniel J. Hoffman
  • Publication number: 20100303680
    Abstract: A plasma reactor for processing a workpiece includes a reactor chamber, an electrostatic chuck within the chamber having a top surface for supporting a workpiece and having indentations in the top surface that form enclosed gas flow channels whenever covered by a workpiece resting on the top surface. The reactor further includes thermal control apparatus thermally coupled to the electrostatic chuck, an RF plasma bias power generator coupled to apply RF power to the electrostatic chuck, a pressurized gas supply of a thermally conductive gas, a controllable gas valve coupling the pressurized gas supply to the indentations to facilitate filling the channels with the thermally conductive gas for heat transfer between a backside of a workpiece and the electrostatic chuck at a heat transfer rate that is a function of the pressure against the backside of the workpiece of the thermally conductive gas.
    Type: Application
    Filed: August 12, 2010
    Publication date: December 2, 2010
    Inventors: Douglas A. Buchberger, JR., Paul Lukas Brillhart, Richard Fovell, Hamid Tavassoli, Douglas H. Burns, Kallol Bera, Daniel J. Hoffman
  • Publication number: 20090159566
    Abstract: A pedestal assembly and method for controlling temperature of a substrate during processing is provided. In one embodiment, method for controlling a substrate temperature during processing includes placing a substrate on a substrate pedestal assembly in a vacuum processing chamber, controlling a temperature of the substrate pedestal assembly by flowing a heat transfer fluid through a radial flowpath within the substrate pedestal assembly, the radial flowpath including both radially inward and radially outward portions, and plasma processing the substrate on the temperature controlled substrate pedestal assembly. In another embodiment, plasma processing may be at least one of a plasma treatment, a chemical vapor deposition process, a physical vapor deposition process, an ion implantation process or an etch process, among others.
    Type: Application
    Filed: December 19, 2008
    Publication date: June 25, 2009
    Applicant: APPLIED MATERIALS, INC.
    Inventors: Paul L. Brillhart, Richard Charles Fovell, Hamid Tavassoli, Xiaoping Zhou, Douglas A. Buchberger, JR., Kallol Bera
  • Publication number: 20070091537
    Abstract: A method of processing a workpiece in a plasma reactor having an electrostatic chuck for holding a workpiece in a chamber of the reactor includes providing a thermally conductive gas under pressure between a backside of the workpiece and a top surface of the electrostatic chuck, controlling the temperature of the electrostatic chuck, defining a desired workpiece temperature, measuring a current workpiece temperature or temperature related to the workpiece temperature and inputting the measured temperature to a thermal model representative of the electrostatic chuck. The method further includes determining from the thermal model a change in the pressure of the thermally conductive gas that would at least reduce the difference between the measured temperature and the desired temperature, and changing the pressure of the thermally conductive gas in accordance with the change determined from the thermal model.
    Type: Application
    Filed: April 21, 2006
    Publication date: April 26, 2007
    Inventors: Douglas Buchberger, Paul Brillhart, Richard Fovell, Hamid Tavassoli, Douglas Burns, Kallol Bera, Daniel Hoffman
  • Publication number: 20070091538
    Abstract: A plasma reactor with a reactor chamber and an electrostatic chuck having a surface for holding a workpiece inside the chamber includes a backside gas pressure source coupled to the electrostatic chuck for applying a thermally conductive gas under a selected pressure into a workpiece-surface interface formed whenever a workpiece is held on the surface, and an evaporator inside the electrostatic chuck and a refrigeration loop having an expansion valve for controlling flow of coolant through the evaporator. The reactor further includes a temperature sensor in the electrostatic chuck, a thermal model capable of simulating heat transfer between the evaporator and the surface based upon measurements from the temperature sensor and an agile control processor coupled to the thermal model and governing the backside gas pressure source in response to predictions from the model of changes in the selected pressure that would bring the temperature measured by the sensor closer to a desired temperature.
    Type: Application
    Filed: April 21, 2006
    Publication date: April 26, 2007
    Inventors: Douglas Buchberger, Paul Brillhart, Richard Fovell, Hamid Tavassoli, Douglas Burns, Kallol Bera, Daniel Hoffman
  • Publication number: 20070089834
    Abstract: A plasma reactor having a reactor chamber and an electrostatic chuck having a surface for holding a workpiece inside the chamber includes inner and outer zone backside gas pressure sources coupled to the electrostatic chuck for applying a thermally conductive gas under respective pressures to respective inner and outer zones of a workpiece-surface interface formed whenever a workpiece is held on the surface, and inner and outer evaporators inside respective inner and outer zones of the electrostatic chuck and a refrigeration loop having respective inner and outer expansion valves for controlling flow of coolant through the inner and outer evaporators respectively. The reactor further includes inner and outer zone temperature sensors in inner and outer zones of the electrostatic chuck and a thermal model capable of simulating heat transfer through the inner and outer zones, respectively, between the evaporator and the surface based upon measurements from the inner and outer temperature sensors, respectively.
    Type: Application
    Filed: April 21, 2006
    Publication date: April 26, 2007
    Inventors: Paul Brillhart, Richard Fovell, Hamid Tavassoli, Douglas Buchberger, Douglas Burns, Kallol Bera, Daniel Hoffman