Patents by Inventor Christopher J. Leavitt

Christopher J. Leavitt 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: 8698107
    Abstract: A time-of-flight (TOF) ion sensor system for monitoring an angular distribution of ion species having an ion energy and incident on a substrate includes a drift tube wherein the ion sensor system is configured to vary an angle of the drift tube with respect to a plane of the substrate. The drift tube may have a first end configured to receive a pulse of ions from the ion species wherein heavier ions and lighter ions of the pulse of ions arrive in packets at a second end of the drift tube. An ion detector may be disposed at the second end of the ion sensor, wherein the ion detector is configured to detect the packets of ions derived from the pulse of ions and corresponding to respective different ion masses.
    Type: Grant
    Filed: January 10, 2011
    Date of Patent: April 15, 2014
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Ludovic Godet, Christopher J. Leavitt, Bon-Woong Koo, Anthony Renau
  • Patent number: 8669538
    Abstract: A system for improving ion beam quality is disclosed. According to one embodiment, the system comprises an ion source, having a chamber defined by a plurality of chamber walls; an RF antenna disposed on a first wall of the plurality of chamber walls; a second wall, opposite the first wall, the distance between the first wall and the second wall defining the height of the chamber; an aperture disposed on one of the plurality of chamber walls; a first gas inlet for introducing a first source gas to the chamber; and a second gas inlet for introducing a second source gas, different from the first source gas, to the chamber; wherein a first distance from the first gas inlet to the second wall is less than 35% of the height; and a second distance from the second gas inlet to the first wall is less than 35% of the height.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: March 11, 2014
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, Christopher J. Leavitt, Peter F. Kurunczi, Timothy J. Miller, Svetlana B. Radovanov
  • Patent number: 8623171
    Abstract: A plasma processing apparatus includes a process chamber, a platen positioned in the process chamber for supporting a workpiece, a source configured to generate a plasma in the process chamber having a plasma sheath adjacent to the front surface of the workpiece, and an insulating modifier. The insulting modifier is configured to control a shape of a boundary between the plasma and the plasma sheath so a portion of the shape of the boundary is not parallel to a plane defined by a front surface of the workpiece facing the plasma. Controlling the shape of the boundary between the plasma and the plasma sheath enables a large range of incident angles of particles striking the workpiece to be achieved.
    Type: Grant
    Filed: April 3, 2009
    Date of Patent: January 7, 2014
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Ludovic Godet, Timothy J. Miller, Christopher J. Leavitt, Bernard G. Lindsay
  • Publication number: 20130146790
    Abstract: A processing system may include a plasma source for providing a plasma and a workpiece holder arranged to receive ions from the plasma. The processing system may further include a pulsed bias circuit electrically coupled to the plasma source and operable to switch a bias voltage supplied to the plasma source between a high voltage state in which the plasma source is biased positively with respect to ground and a low voltage state in which the plasma source is biased negatively with respect to the ground.
    Type: Application
    Filed: December 7, 2011
    Publication date: June 13, 2013
    Applicant: Varian Semiconductor Equipment Associates, INC.
    Inventors: Peter F. Kurunczi, Christopher J. Leavitt, Daniel Distaso, Timothy J. Miller
  • Patent number: 8461554
    Abstract: A processing system may include a plasma source for providing a plasma and a workpiece holder arranged to receive ions from the plasma. The processing system may further include a pulsed bias circuit electrically coupled to the plasma source and operable to switch a bias voltage supplied to the plasma source between a high voltage state in which the plasma source is biased positively with respect to ground and a low voltage state in which the plasma source is biased negatively with respect to the ground.
    Type: Grant
    Filed: December 7, 2011
    Date of Patent: June 11, 2013
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Peter F. Kurunczi, Christopher J. Leavitt, Daniel Distaso, Timothy J. Miller
  • Patent number: 8354655
    Abstract: A method of treating a photoresist relief feature having an initial line roughness and an initial critical dimension. The method may include directing ions toward the photoresist in a first exposure at a first angular range and first dose rate and a that is configured to reduce the initial line roughness to a second line roughness. The method may also include directing ions toward the photoresist relief feature in a second exposure at a second ion dose rate greater than the first dose rate, wherein the second ion dose rate is configured to swell the photoresist relief feature.
    Type: Grant
    Filed: May 3, 2011
    Date of Patent: January 15, 2013
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Ludovic Godet, Christopher J. Leavitt, Joseph C. Olson, Patrick M. Martin
  • Publication number: 20120280140
    Abstract: A method of treating a photoresist relief feature having an initial line roughness and an initial critical dimension. The method may include directing ions toward the photoresist in a first exposure at a first angular range and first dose rate and a that is configured to reduce the initial line roughness to a second line roughness. The method may also include directing ions toward the photoresist relief feature in a second exposure at a second ion dose rate greater than the first dose rate, wherein the second ion dose rate is configured to swell the photoresist relief feature.
    Type: Application
    Filed: May 3, 2011
    Publication date: November 8, 2012
    Applicant: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.
    Inventors: Ludovic Godet, Christopher J. Leavitt, Joseph C. Olson, Patrick M. Martin
  • Publication number: 20120228515
    Abstract: A method of implanting a workpiece in an ion implantation system. The method may include providing an extraction plate adjacent to a plasma chamber containing a plasma, such that the extraction plate extracts ions from the plasma through at least one aperture that provides an ion beam having ions distributed over a range of an angles of incidence on the workpiece. The method may include scanning the workpiece with respect to the extraction plate and varying a power level of the plasma during the scanning from a first power level to a second power level, wherein at a surface of the workpiece, a first beam width at a first power level is greater than a second beam width at a second power level.
    Type: Application
    Filed: March 11, 2011
    Publication date: September 13, 2012
    Applicant: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.
    Inventors: Christopher J. Leavitt, Ludovic Godet, Timothy J. Miller
  • Publication number: 20120175518
    Abstract: A time-of-flight (TOF) ion sensor system for monitoring an angular distribution of ion species having an ion energy and incident on a substrate includes a drift tube wherein the ion sensor system is configured to vary an angle of the drift tube with respect to a plane of the substrate. The drift tube may have a first end configured to receive a pulse of ions from the ion species wherein heavier ions and lighter ions of the pulse of ions arrive in packets at a second end of the drift tube. An ion detector may be disposed at the second end of the ion sensor, wherein the ion detector is configured to detect the packets of ions derived from the pulse of ions and corresponding to respective different ion masses.
    Type: Application
    Filed: January 10, 2011
    Publication date: July 12, 2012
    Applicant: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.
    Inventors: Ludovic Godet, Christopher J. Leavitt, Bon-Woong Koo, Anthony Renau
  • Publication number: 20120000421
    Abstract: A control apparatus for plasma immersion ion implantation of a dielectric substrate which includes an electrode disposed above a generated plasma in a plasma chamber. The electrode is biased with negative voltage pulses at a potential that is higher than a potential of a substrate or cathode configured to receive ion implantation. The electrode is more negative to give the electrons generated as secondary electrons from the electrode sufficient energy to overcome the negative voltage of the high voltage sheath around the substrate thereby reaching the substrate. These electrons are accelerated toward the substrate to neutralize charge build-up on the substrate.
    Type: Application
    Filed: July 2, 2010
    Publication date: January 5, 2012
    Applicant: Varian Semicondutor Equipment Associates, Inc.
    Inventors: Timothy Miller, Vikram Singh, Ludo Godet, Christopher J. Leavitt
  • Publication number: 20100255683
    Abstract: A plasma processing apparatus includes a process chamber, a platen positioned in the process chamber for supporting a workpiece, a source configured to generate a plasma in the process chamber having a plasma sheath adjacent to the front surface of the workpiece, and an insulating modifier. The insulting modifier is configured to control a shape of a boundary between the plasma and the plasma sheath so a portion of the shape of the boundary is not parallel to a plane defined by a front surface of the workpiece facing the plasma. Controlling the shape of the boundary between the plasma and the plasma sheath enables a large range of incident angles of particles striking the workpiece to be achieved.
    Type: Application
    Filed: April 3, 2009
    Publication date: October 7, 2010
    Applicant: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES
    Inventors: Ludovic GODET, Timothy J. Miller, Christopher J. Leavitt, Bernard G. Lindsay
  • Publication number: 20100155600
    Abstract: An non-Faraday ion dose measurement device is positioned within a plasma process chamber and includes a sensor located above a workpiece within the chamber. The sensor is configured to detect the number of secondary electrons emitted from a surface of the workpiece exposed to a plasma implantation process. The sensor outputs a current signal proportional to the detected secondary electrons. A current circuit subtracts the detected secondary current generated from the sensor and subtracts it from a bias current supplied to the workpiece within the chamber. The difference between the currents provides a measurement of the ion dose current calculated in situ and during the implantation process.
    Type: Application
    Filed: December 23, 2008
    Publication date: June 24, 2010
    Applicant: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Joseph P Dzengeleski, Timothy J. Miler, Jay T. Scheuer, Christopher J. Leavitt
  • Publication number: 20080160212
    Abstract: A method and apparatuses for providing improved electrical contact to a semiconductor wafer during plasma processing applications are disclosed. In one embodiment, an apparatus includes a wafer platen for supporting the wafer; and a plurality of electrical contact elements, each of the plurality of electrical contact elements are configured to provide a path for supplying a bias voltage from a bias power supply to the wafer on the wafer platen. The plurality of electrical contact elements are also geometrically arranged such that at least one electrical contact element contacts an inner surface region (e.g., region between a center of wafer and a distance approximately half of the radius of the wafer) and at least one electrical contact element contacts an outer annular surface region (e.g., region between an outer edge of wafer and a distance approximately half of the radius of the wafer).
    Type: Application
    Filed: December 27, 2006
    Publication date: July 3, 2008
    Inventors: Bon-Woong Koo, Steven R. Walther, Christopher J. Leavitt, Justin Tocco, Sung-Hwan Hyun, Timothy J. Miller, Jay T. Scheuer, Atul Gupta, Vikram Singh, Deven Raj