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: 9520259
    Abstract: A plasma chamber having improved controllability of the ion density of the extracted ribbon ion beam is disclosed. A plurality of pairs of RF biased electrodes is disposed on opposite sides of the extraction aperture in a plasma chamber. In some embodiments, one of each pair of RF biased electrodes is biased at the extraction voltage, while the other of each pair is coupled to a RF bias power supply, which provides a RF voltage having a DC component and an AC component. In another embodiment, both of the electrodes in each pair are coupled to a RF biased power supply. A blocker may be disposed in the plasma chamber near the extraction aperture. In some embodiments, RF biased electrodes are disposed on the blocker.
    Type: Grant
    Filed: November 23, 2015
    Date of Patent: December 13, 2016
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Alexandre Likhanskii, Svetlana B. Radovanov, Bon-Woong Koo
  • Patent number: 9478679
    Abstract: A method of processing a solar cell is disclosed, where the edges of the solar cell are covered, coated or masked during the ion implantation process and/or the screen printing process. This covering may be a substance that blocks the penetration of ions during implantation, or may be a substance that resists the diffusion of fritted metal paste during the metallization process. In some embodiments, the edges are covered during both of these processes. In further embodiments, the same material may perform both functions.
    Type: Grant
    Filed: November 24, 2014
    Date of Patent: October 25, 2016
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Nicholas P. T. Bateman, Vikram M. Bhosle, Bon-Woong Koo
  • Patent number: 9441290
    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: Grant
    Filed: May 29, 2013
    Date of Patent: September 13, 2016
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, Min-Sung Jeon, Yong-Tae Kim, Timothy J. Miller
  • Publication number: 20160163510
    Abstract: An apparatus and methods of improving the ion beam quality of a halogen-based source gas are disclosed. Unexpectedly, the introduction of a noble gas, such as argon, to an ion source chamber may increase the percentage of desirable ion species, while decreasing the amount of contaminants and halogen-containing ions. This is especially beneficial in non-mass analyzed implanters, where all ions are implanted into the workpiece. In one embodiment, a first source gas, comprising a dopant and a halogen is introduced into an ion source chamber, a second source gas comprising a hydride, and a third source gas comprising a noble gas are also introduced. The combination of these three source gases produces an ion beam having a higher percentage of pure dopant ions than would occur if the third source gas were not used.
    Type: Application
    Filed: November 23, 2015
    Publication date: June 9, 2016
    Inventors: Bon-Woong Koo, Vikram M. Bhosle, John A. Frontiero, Nicholas P.T. Bateman, Timothy J. Miller, Svetlana B. Radovanov, Min-Sung Jeon, Peter F. Kurunczi, Christopher J. Leavitt
  • Publication number: 20160163509
    Abstract: An apparatus and methods of improving the ion beam quality of a halogen-based source gas are disclosed. Unexpectedly, the introduction of a noble gas, such as argon or neon, to an ion source chamber may increase the percentage of desirable ion species, while decreasing the amount of contaminants and halogen-containing ions. This is especially beneficial in non-mass analyzed implanters, where all ions are implanted into the workpiece. In one embodiment, a first source gas, comprising a processing species and a halogen is introduced into a ion source chamber, a second source gas comprising a hydride, and a third source gas comprising a noble gas are also introduced. The combination of these three source gases produces an ion beam having a higher percentage of pure processing species ions than would occur if the third source gas were not used.
    Type: Application
    Filed: April 21, 2015
    Publication date: June 9, 2016
    Inventors: Bon-Woong Koo, Vikram M. Bhosle, John A. Frontiero
  • Publication number: 20160111241
    Abstract: A plasma chamber having improved controllability of the ion density of the extracted ribbon ion beam is disclosed. A plurality of pairs of RF biased electrodes is disposed on opposite sides of the extraction aperture in a plasma chamber. In some embodiments, one of each pair of RF biased electrodes is biased at the extraction voltage, while the other of each pair is coupled to a RF bias power supply, which provides a RF voltage having a DC component and an AC component. In another embodiment, both of the electrodes in each pair are coupled to a RF biased power supply. A blocker may be disposed in the plasma chamber near the extraction aperture. In some embodiments, RF biased electrodes are disposed on the blocker.
    Type: Application
    Filed: November 23, 2015
    Publication date: April 21, 2016
    Inventors: Alexandre Likhanskii, Svetlana B. Radovanov, Bon-Woong Koo
  • Patent number: 9297063
    Abstract: An ion implantation system including a plasma source, a mask-slit, and a plasma chamber. The plasma source is configured to generate a plasma within the plasma chamber in response to the introduction of a gas therein. The mask-slit is electrically isolated from the plasma chamber. A positive voltage bias is applied to the plasma chamber above a bias potential used to generate the plasma. The positive voltage bias drives the plasma potential to accelerate the ions to a desired implant energy. The accelerated ions pass through an aperture in the mask-slit and are directed toward a substrate for implantation. The mask-slit is electrically isolated from the plasma chamber and is maintained at ground potential with respect to the plasma.
    Type: Grant
    Filed: April 26, 2012
    Date of Patent: March 29, 2016
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Svetlana B. Radovanov, Victor M. Benveniste, Bon-Woong Koo, Richard M. White, Kevin M. Daniels
  • Patent number: 9288889
    Abstract: A processing system includes a plasma source chamber to generate a plasma; an extraction assembly adjacent the plasma source chamber having an extraction plate and a beam modifier, the extraction plate defining an extraction plate plane and an aperture to extract ions from the plasma source chamber into an ion beam, the beam modifier adjacent to the extraction plate and operative to adjust an ion beam trajectory angle of the ion beam with respect to a perpendicular to the extraction plate plane; and a neutralizer to receive the ion beam extracted by the extraction assembly, convert the ion beam to a neutral beam and direct the neutral beam towards a substrate, the neutralizer having one or more neutralizer plates arranged at a neutralizer plate angle, the extraction assembly and the neutralizer interoperative to provide an ion beam incident angle of the ion beam with respect to the neutralizer plates.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: March 15, 2016
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Svetlana B. Radovanov, Bon-Woong Koo, Peter F. Kurunczi, Ludovic Godet
  • Patent number: 9230773
    Abstract: A plasma chamber having improved controllability of the ion density of the extracted ribbon ion beam is disclosed. A plurality of pairs of RF biased electrodes is disposed on opposite sides of the extraction aperture in a plasma chamber. In some embodiments, one of each pair of RF biased electrodes is biased at the extraction voltage, while the other of each pair is coupled to a RF bias power supply, which provides a RF voltage having a DC component and an AC component. In another embodiment, both of the electrodes in each pair are coupled to a RF biased power supply. A blocker may be disposed in the plasma chamber near the extraction aperture. In some embodiments, RF biased electrodes are disposed on the blocker.
    Type: Grant
    Filed: October 16, 2014
    Date of Patent: January 5, 2016
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Alexandre Likhanskii, Svetlana B. Radovanov, Bon-Woong Koo
  • Patent number: 9232628
    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: Grant
    Filed: February 20, 2013
    Date of Patent: January 5, 2016
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Svetlana B. Radovanov, Ludovic Godet, Bon-Woong Koo
  • Publication number: 20150354056
    Abstract: A method of processing a workpiece is disclosed, where the plasma chamber is first coated using a conditioning gas and optionally, a co-gas. The conditioning gas, which is disposed within a conditioning gas container may comprise a hydride of the desired dopant species and a filler gas, where the filler gas is a hydride of a Group 4 or Group 5 element. The remainder of the conditioning gas container may comprise hydrogen gas. Following this conditioning process, a feedgas, which comprises fluorine and the desired dopant species, is introduced to the plasma chamber and ionized. Ions are then extracted from the plasma chamber and accelerated toward the workpiece, where they are implanted without being first mass analyzed. In some embodiments, the desired dopant species may be boron.
    Type: Application
    Filed: June 6, 2014
    Publication date: December 10, 2015
    Inventors: Bon-Woong Koo, Christopher J. Leavitt, John A. Frontiero, Timothy J. Miller, Svetlana B. Radovanov
  • Patent number: 9196489
    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: Grant
    Filed: January 25, 2013
    Date of Patent: November 24, 2015
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Vikram Bhosle, Bon-Woong Koo
  • Publication number: 20150270421
    Abstract: An improved method of manufacturing a back contact solar cell is disclosed. The method is particularly beneficial to the creation of interdigitated back contact (IBC) solar cells. A mask paste is applied to the tunnel oxide layer. Silicon is deposited on the tunnel oxide layer. The placement of the mask paste causes discrete regions of deposited silicon to be created. Using a shadow mask, dopant is implanted into one or more of these discrete and separate regions. After the implanting of dopant, metal is sputtered onto the deposited silicon to create electrodes. Following the deposition of the metal layer, the mask paste is removed, such as using a wet etch process. The resulting solar cell has discrete doped regions each with a corresponding electrode applied thereon. These discrete doped regions are separated by a gap, which extends to the tunnel oxide layer.
    Type: Application
    Filed: March 20, 2014
    Publication date: September 24, 2015
    Inventors: Min-Sung Jeon, Bon-Woong Koo
  • Patent number: 9142379
    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 8, 2014
    Date of Patent: September 22, 2015
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, Christopher R. Campbell, Craig R. Chaney, Robert C. Lindberg, Wilhelm P. Platow, Alexander S. Perel
  • Patent number: 9093372
    Abstract: Techniques for processing a substrate are disclosed. In one exemplary embodiment, the technique may be realized with an ion implantation system for processing a substrate.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: July 28, 2015
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, Richard M. White, Svetlana B. Radovanov, Kevin M. Daniels, Eric R. Cobb, David W. Pitman
  • Publication number: 20150179455
    Abstract: Techniques for processing a substrate are disclosed. In one exemplary embodiment, the technique may be realized as a method for processing a substrate, the method comprising: ionizing first material and second material in an ion source chamber of an ion source, the first material being boron (B) containing material, the second material being one of phosphorous (P) containing material and arsenic (As) containing material; generating first ions containing B and second ions containing one of P and As; and extracting the first and second ions from the ion source chamber and directing the first and second ions toward the substrate.
    Type: Application
    Filed: February 27, 2015
    Publication date: June 25, 2015
    Inventors: Bon-Woong Koo, Richard M. White, Svetlana B. Radovanov, Kevin M. Daniels, Eric R. Cobb, David W. Pitman
  • Patent number: 9062377
    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: Grant
    Filed: September 23, 2013
    Date of Patent: June 23, 2015
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: William T. Levay, George M. Gammel, Bon-Woong Koo, Brant S. Binns, Richard M. White
  • Patent number: 9064795
    Abstract: Techniques for processing a substrate are disclosed. In one exemplary embodiment, the technique may be realized as a method for processing a substrate, the method comprising: ionizing first material and second material in an ion source chamber of an ion source, the first material being boron (B) containing material, the second material being one of phosphorous (P) containing material and arsenic (As) containing material; generating first ions containing B and second ions containing one of P and As; and extracting the first and second ions from the ion source chamber and directing the first and second ions toward the substrate.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: June 23, 2015
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Bon-Woong Koo, Richard M. White, Svetlana B. Radovanov, Kevin M. Daniels, Eric R. Cobb, David W. Pitman
  • Publication number: 20150162457
    Abstract: A method of processing a solar cell is disclosed, where the edges of the solar cell are covered, coated or masked during the ion implantation process and/or the screen printing process. This covering may be a substance that blocks the penetration of ions during implantation, or may be a substance that resists the diffusion of fritted metal paste during the metallization process. In some embodiments, the edges are covered during both of these processes. In further embodiments, the same material may perform both functions.
    Type: Application
    Filed: November 24, 2014
    Publication date: June 11, 2015
    Inventors: Nicholas P.T. Bateman, Vikram M. Bhosle, Bon-Woong Koo
  • Patent number: 9034743
    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: Grant
    Filed: November 26, 2013
    Date of Patent: May 19, 2015
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    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 P T Bateman