Patents by Inventor Bon-Woong Koo

Bon-Woong Koo 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: 9018829
    Abstract: An ion source includes an ion chamber housing defining an ion source chamber, the ion chamber housing having a side with a plurality of apertures. The ion source also includes an antechamber housing defining an antechamber. The antechamber housing shares the side with the plurality of apertures with the ion chamber housing. The antechamber housing has an opening to receive a gas from a gas source. The antechamber is configured to transform the gas into an altered state having excited neutrals that is provided through the plurality of apertures into the ion source chamber.
    Type: Grant
    Filed: July 31, 2013
    Date of Patent: April 28, 2015
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, Victor Benveniste, Christopher A. Rowland, Craig R. Chaney, Frank Sinclair, Neil J. Bassom
  • Publication number: 20150034837
    Abstract: An ion source includes an ion source chamber, a gas source to provide a fluorine-containing gas species to the ion source chamber and a cathode disposed in the ion source chamber configured to emit electrons to generate a plasma within the ion source chamber. The ion source chamber and cathode are comprised of a refractory metal. A phosphide insert is disposed within the ion source chamber and presents an exposed surface area that is configured to generate gas phase phosphorous species when the plasma is present in the ion source chamber, wherein the phosphide component is one of boron phosphide, tungsten phosphide, aluminum phosphide, nickel phosphide, calcium phosphide and indium phosphide.
    Type: Application
    Filed: August 1, 2013
    Publication date: February 5, 2015
    Applicant: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, William T. Levay, Richard M. White, Eric R. Cobb
  • Publication number: 20150024579
    Abstract: A method for improving the ion beam quality in an ion implanter is disclosed. In some ion implantation systems, contaminants from the ion source are extracted with the desired ions, introducing contaminants to the workpiece. These contaminants may be impurities in the ion source chamber. This problem is exacerbated when mass analysis of the extracted ion beam is not performed, and is further exaggerated when the desired feedgas includes a halogen. The introduction of a diluent gas in the ion chamber may reduce the deleterious effects of the halogen on the inner surfaces of the chamber, reducing contaminants in the extracted ion beam. In some embodiments, the diluent gas may be germane or silane.
    Type: Application
    Filed: November 26, 2013
    Publication date: January 22, 2015
    Applicant: Varian Semiconductor Equipment Associates, Inc.
    Inventors: John W. Graff, Bon-Woong Koo, John A. Frontiero, Nicholas PT Bateman, Timothy J. Miller, Vikram M. Bhosle
  • Publication number: 20150024580
    Abstract: A method of processing a workpiece is disclosed, where the ion chamber is first coated with the desired dopant species and another species. Following this conditioning process, a feedgas, which comprises fluorine and the desired dopant, is introduced to the chamber and ionized. Ions are then extracted from the chamber and accelerated toward the workpiece, where they are implanted without being first mass analyzed. The other species used during the conditioning process may be a Group 3, 4 or 5 element. The desired dopant species may be boron.
    Type: Application
    Filed: November 26, 2013
    Publication date: January 22, 2015
    Inventors: Peter F. Kurunczi, Bon-Woong Koo, John A. Frontiero, William T. Levay, Christopher J. Leavitt, Timothy J. Miller, Vikram M. Bhosle, John W. Graff, Nicholas PT Bateman
  • Publication number: 20150007941
    Abstract: A plasma processing apparatus includes a process chamber housing defining a process chamber, a platen positioned in the process chamber for supporting a workpiece, a source configured to generate plasma in the process chamber, and a biasing system. The biasing system is configured to bias the platen with a negatively biased DC signal to attract ions from the plasma towards the workpiece during a first processing time interval and configured to bias the platen with a positively biased DC signal to repel ions from the platen towards interior surfaces of the process chamber housing during a cleaning time interval. The cleaning time interval is separate from the first processing time interval and occurs after the first processing time interval.
    Type: Application
    Filed: September 24, 2014
    Publication date: January 8, 2015
    Inventors: Bon-Woong Koo, Richard M. White
  • Patent number: 8916056
    Abstract: A plasma processing apparatus includes a process chamber housing defining a process chamber, a platen positioned in the process chamber for supporting a workpiece, a source configured to generate plasma in the process chamber, and a biasing system. The biasing system is configured to bias the platen to attract ions from the plasma towards the workpiece during a first processing time interval and configured to bias the platen to repel ions from the platen towards interior surfaces of the process chamber housing during a cleaning time interval. The cleaning time interval is separate from the first processing time interval and occurring after the first processing time interval.
    Type: Grant
    Filed: October 11, 2012
    Date of Patent: December 23, 2014
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, Richard M. White
  • Publication number: 20140356547
    Abstract: A system and method for the removal of deposited material from the walls of a plasma chamber is disclosed. The system may have two modes; a normal operating mode and a cleaning mode. During the cleaning mode, the plasma is biased at a higher potential than the walls, thereby causing energetic ions from the plasma to strike the plasma wall, dislodging material previously deposited. This may be achieved through the use of one or more electrodes disposed in the plasma chamber, which are maintained at a first voltage during normal operating mode, and a second, higher voltage, during the cleaning mode.
    Type: Application
    Filed: May 29, 2013
    Publication date: December 4, 2014
    Applicant: Varian Semiconductor Equipment Associates Inc.
    Inventors: Bon-Woong Koo, Min-Sung Jeon, Yong-Tae Kim, Timothy J. Miller
  • Publication number: 20140319369
    Abstract: An ion source and method of cleaning are disclosed. One or more heating units are placed in close proximity to the inner volume of the ion source, so as to affect the temperature within the ion source. In one embodiment, one or more walls of the ion source have recesses into which heating units are inserted. In another embodiment, one or more walls of the ion source are constructed of a conducting circuit and an insulating layer. By utilizing heating units near the ion source, it is possible to develop new methods of cleaning the ion source. Cleaning gas is flowed into the ion source, where it is ionized, either by the cathode, as in normal operating mode, or by the heat generated by the heating units. The cleaning gas is able to remove residue from the walls of the ion source more effectively due to the elevated temperature.
    Type: Application
    Filed: July 8, 2014
    Publication date: October 30, 2014
    Inventors: Bon-Woong Koo, Christopher R. Campbell, Craig R. Chaney, Robert C. Lindberg, Wilhelm P. Platow, Alexander S. Perel
  • Patent number: 8834732
    Abstract: A technique for processing a workpiece is disclosed. In accordance with one exemplary embodiment, the technique is realized as a method for processing a substrate, where the method comprises: providing the workpiece in the chamber; providing a plurality of electrodes between a wall of the chamber and the workpiece; generating a plasma containing ions between the plurality of electrodes and the workpiece, ion density in an inner portion of the plasma being greater than the ion density in an outer portion of the plasma portion, the outer portion being between the inner portion and the wall of the chamber; and providing a bias voltage to the plurality of electrodes and dispersing at least a portion of the ions in the inner portion until the ion density in the inner portion is substantially equal to the ion density in the periphery plasma portion.
    Type: Grant
    Filed: October 26, 2012
    Date of Patent: September 16, 2014
    Inventor: Bon-Woong Koo
  • Publication number: 20140234554
    Abstract: A system for processing a substrate may include a first chamber operative to define a first plasma and a second chamber adjacent the first chamber, where the second chamber is electrically isolated from the first chamber, and configured to define a second plasma. The system may also include an extraction assembly disposed between the first chamber and second chamber to provide at least plasma isolation between the first plasma and the second plasma, a substrate assembly configured to support the substrate in the second chamber; and a biasing system configured to supply a plurality of first voltage pulses to direct first ions from the first plasma through the second chamber towards the substrate during one time period, and to supply a plurality of second voltage pulses to generate the second plasma and to attract second ions from the second plasma during another time period.
    Type: Application
    Filed: February 20, 2013
    Publication date: August 21, 2014
    Applicant: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.
    Inventors: Svetlana B. Radovanov, Ludovic Godet, Bon-Woong Koo
  • Patent number: 8809800
    Abstract: An ion source and method of cleaning are disclosed. One or more heating units are placed in close proximity to the inner volume of the ion source, so as to affect the temperature within the ion source. In one embodiment, one or more walls of the ion source have recesses into which heating units are inserted. In another embodiment, one or more walls of the ion source are constructed of a conducting circuit and an insulating layer. By utilizing heating units near the ion source, it is possible to develop new methods of cleaning the ion source. Cleaning gas is flowed into the ion source, where it is ionized, either by the cathode, as in normal operating mode, or by the heat generated by the heating units. The cleaning gas is able to remove residue from the walls of the ion source more effectively due to the elevated temperature.
    Type: Grant
    Filed: July 31, 2009
    Date of Patent: August 19, 2014
    Assignee: Varian Semicoductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, Christopher R. Campbell, Craig R. Chaney, Robert Lindberg, Wilhelm P. Platow, Alexander S. Perel
  • Publication number: 20140213014
    Abstract: A method of tailoring the dopant profile of a workpiece by modulating one or more operating parameters is disclosed. In one embodiment, the workpiece may be a solar cell and the desired dopant profile may include a heavily doped surface region and a highly doped region. These two regions can be generated by varying one or more of the parameters of the ion implanter. For example, the extraction voltage may be changed to affect the energy of the implanted ions. The ionization energy can be changed to affect the species of ions being generated from the source gas. In another embodiment, the source gasses that are ionized may be changed to affect the species being generated. After the implant has been performed, thermal processing is performed which minimizes the diffusion of the ions in the workpiece.
    Type: Application
    Filed: January 25, 2013
    Publication date: July 31, 2014
    Applicant: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.
    Inventors: Vikram Bhosle, Bon-Woong Koo
  • Patent number: 8756021
    Abstract: A method of controlling operation of an indirectly-heated cathode (IHC) ion source includes a step of measuring a rate of loss of cathode weight of the IHC ion source that occurs during operation using a first cathode configuration and under a first set of operation conditions. A maximum weight loss for the first cathode configuration is determined, and a cathode lifetime is calculated based upon the rate of cathode weight loss and the maximum weight loss. A further method includes receiving a minimum source bias power value for operation of a cathode in a first configuration, measuring a rate of decrease in source bias power for a cathode in the first configuration, and calculating a lifetime of the cathode based upon the minimum source bias power and rate of decrease in source bias power.
    Type: Grant
    Filed: October 26, 2010
    Date of Patent: June 17, 2014
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Russell J. Low, Kevin M. Daniels, Bon-Woong Koo, Richard M. White, James W. Blanchette
  • Publication number: 20140127394
    Abstract: Methods of reducing glitch rates within an ion implanter are described. In one embodiment, a plasma-assisted conditioning is performed, wherein the bias voltage to the extraction electrodes is modified so as to inhibit the formation of an ion beam. The power supplied to the plasma generator in the ion source is increased, thereby creating a high density plasma, which is not extracted by the extraction electrodes. This plasma extends from the arc chamber through the extraction aperture. Energetic ions then condition the extraction electrodes. In another embodiment, a plasma-assisted cleaning is performed. In this mode, the extraction voltage applied to the arc chamber body is modulated between two voltages so as to clean both the extraction electrodes and the faceplate of the arc chamber body.
    Type: Application
    Filed: October 25, 2013
    Publication date: May 8, 2014
    Inventors: George M. Gammel, Brant S. Binns, Piotr R. Lubicki, Bon-Woong Koo, Richard M. White, Kevin M. Daniels
  • Publication number: 20140106571
    Abstract: A plasma processing apparatus includes a process chamber housing defining a process chamber, a platen positioned in the process chamber for supporting a workpiece, a source configured to generate plasma in the process chamber, and a biasing system. The biasing system is configured to bias the platen to attract ions from the plasma towards the workpiece during a first processing time interval and configured to bias the platen to repel ions from the platen towards interior surfaces of the process chamber housing during a cleaning time interval. The cleaning time interval is separate from the first processing time interval and occurring after the first processing time interval.
    Type: Application
    Filed: October 11, 2012
    Publication date: April 17, 2014
    Applicant: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, Richard M. White
  • 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
  • Publication number: 20140097752
    Abstract: A plasma ion source including a plasma chamber, gas inlets, an RF antenna, an RF window, an extraction plate, a window shield, and a chamber liner. The RF window may be positioned intermediate the RF antenna and the plasma chamber. The window shield may be disposed intermediate the RF widow and the interior of the plasma chamber and the chamber liner may cover the interior surface of the plasma chamber. During operation of the ion source, the window shield sustains ionic bombardment that would otherwise be sustained by the RF window. Fewer impurity ions are therefore released into the plasma chamber. Simultaneously, additional dopant atoms are released from the window shield into the plasma chamber. Ionic bombardment is also sustained by the chamber liner, which also contributes a quantity of dopant atoms to the plasma chamber. Dopant ion production within the plasma chamber is thereby increased while impurities are minimized.
    Type: Application
    Filed: October 9, 2012
    Publication date: April 10, 2014
    Applicant: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.
    Inventors: Costel Biloui, Timonthy J. Miller, Bon-Woong Koo, Anthony Renau
  • Publication number: 20140099430
    Abstract: Methods of reducing glitch rates within an ion implanter are described. In one embodiment, a plasma-assisted conditioning is performed, wherein the bias voltage to the extraction electrodes is modified so as to inhibit the formation of an ion beam. The power supplied to the plasma generator in the ion source is increased, thereby creating a high density plasma, which is not extracted by the extraction electrodes. This plasma extends from the ion source chamber through the extraction aperture. Energetic ions then condition the extraction electrodes. In another embodiment, a plasma-assisted cleaning is performed. In this mode, the extraction electrodes are moved further from the ion source chamber, and a different source gas is used to create the plasma. In some embodiments, a combination of these modes is used to reduce glitches in the ion implanter.
    Type: Application
    Filed: September 23, 2013
    Publication date: April 10, 2014
    Inventors: William T. Levay, George M. Gammel, Bon-Woong Koo, Brant S. Binns, Richard M. White
  • 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
  • Publication number: 20140021373
    Abstract: An ion implantation system and method are disclosed in which glitches in voltage are minimized by use of a modulated power supply system in the implanter. The modulated power supply system includes a traditional power supply and a control unit associated with each power supply, where the control unit is used to isolate the power supply from an electrode if a glitch or arc is detected. The control unit then restores connectivity after the glitch condition has been rectified.
    Type: Application
    Filed: July 23, 2012
    Publication date: January 23, 2014
    Applicant: VARIAN SEMICONDUCTOR EQUIPMENT ASSOCIATES, INC.
    Inventors: Piotr Lubicki, Christopher Leavitt, Timothy Miller, Bon-Woong Koo