Patents by Inventor Keita Kitade

Keita Kitade 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: 8173037
    Abstract: A wafer polish monitoring method and device for detecting the end point of the polishing of a conductive film with high precision and accuracy by monitoring the variation of the film thickness of the conductive film without adverse influence of slurry or the like after the film thickness of the conductive film decreases to an extremely small film thickness defined by the skin depth. A high-frequency transmission path is formed in a portion facing the conductive film on the surface of the wafer, the polishing removal state of the conductive film is evaluated based at least on the transmitted electromagnetic waves passing through the high-frequency transmission path or the reflected electromagnetic waves that are reflected without passing through the high-frequency transmission path, and the end point of the polishing removal and the point equivalent to the end point of the polishing removal are detected.
    Type: Grant
    Filed: January 10, 2008
    Date of Patent: May 8, 2012
    Assignee: Tokyo Semitsu Co. Ltd
    Inventors: Takashi Fujita, Toshiyuki Yokoyama, Keita Kitade
  • Patent number: 7830141
    Abstract: Coil is made to be disposed with gap opposed to the surface of wafer, and wafer stage is made to move in X and Y direction and R and ? direction. When supplying an alternating current to coil with the frequency swept by impedance analyzer, the magnetic field made to be induced in coil will operate on the conductive film of wafer. By changing a parameter (a frequency or an angle) influencing the skin effect of the conductive film and giving the parameter to coil, the state where a magnetic field is not made to penetrate relatively the film of wafer and the state where the magnetic field is made to penetrate relatively the film can be formed. From the variation of various values corresponding to the eddy current induced based on the change of state influenced by the skin effect of the conductive film, the film thickness of wafer can be measured with sufficient accuracy.
    Type: Grant
    Filed: January 7, 2009
    Date of Patent: November 9, 2010
    Assignee: Tokyo Seimitsu Co., Ltd.
    Inventors: Takashi Fujita, Toshiyuki Yokoyama, Keita Kitade
  • Patent number: 7821257
    Abstract: A method and device for forecasting/detecting a polishing end point and for monitoring a real-time film thickness to suppress Joule heat loss due to the eddy current to the minimum, to precisely forecast/detect a polishing end point, to precisely calculate the remaining film thickness to be removed, and polishing rate.
    Type: Grant
    Filed: August 18, 2008
    Date of Patent: October 26, 2010
    Assignee: Tokyo Seimitsu Co., Ltd
    Inventors: Takashi Fujita, Toshiyuki Yokoyama, Keita Kitade
  • Patent number: 7795865
    Abstract: A method and device for forecasting and detecting a polishing endpoint and real time film thickness monitoring capable of suppressing to a minimum Joule heat loss due to an eddy current, and precisely forecasting and detecting the polishing endpoint, and precisely calculating a remaining film amount to be removed and a polishing rate. A high frequency inductor sensor is positioned close to the conductive film, and monitors a flux change induced in the conductive film. When a film thickness becomes a film thickness corresponding to a skin depth of the conductive film a method of calculating on the spot a polishing rate and a remaining film amount to be removed is provided.
    Type: Grant
    Filed: October 18, 2007
    Date of Patent: September 14, 2010
    Assignee: Tokyo Seimitsu Co., Ltd.
    Inventors: Takashi Fujita, Toshiyuki Yokoyama, Keita Kitade
  • Publication number: 20090256558
    Abstract: Coil is made to be disposed with gap opposed to the surface of wafer, and wafer stage is made to move in X and Y direction and R and ? direction. When supplying an alternating current to coil with the frequency swept by impedance analyzer, the magnetic field made to be induced in coil will operate on the conductive film of wafer. By changing a parameter (a frequency or an angle) influencing the skin effect of the conductive film and giving the parameter to coil, the state where a magnetic field is not made to penetrate relatively the film of wafer and the state where the magnetic field is made to penetrate relatively the film can be formed. From the variation of various values corresponding to the eddy current induced based on the change of state influenced by the skin effect of the conductive film, the film thickness of wafer can be measured with sufficient accuracy.
    Type: Application
    Filed: January 7, 2009
    Publication date: October 15, 2009
    Inventors: Takashi Fujita, Toshiyuki Yokoyama, Keita Kitade
  • Publication number: 20090061733
    Abstract: [Problem to be Solved] To provide a method and device for forecasting/detecting a polishing end point and a method and device for monitoring a real-time film thickness to suppress Joule heat loss due to the eddy current to the minimum, to precisely forecast/detect an polishing end point, to precisely calculate the remaining film thickness to be removed, polishing rate and the like on the spot, and to precisely evaluate whether the predetermined conductive film is appropriately removed [Solution] In order to achieve the object, according to the present invention, there is provided a method wherein an inductor 36 in a high frequency inductor type sensor is arranged adjacent to a predetermined conductive film 28, and a magnetic flux change induced in the predetermined conductive film 28 by a magnetic flux formed of the inductor 36 is monitored, and by use of a magnetic flux change when a film thickness becomes corresponding to skin depth in which a film thickness in polishing is determined by the material of the
    Type: Application
    Filed: August 18, 2008
    Publication date: March 5, 2009
    Inventors: Takashi Fujita, Toshiyuki Yokoyama, Keita Kitade
  • Publication number: 20080290865
    Abstract: An object of the present invention is to provide a method of forecasting and detecting a polishing endpoint and the device thereof and a real time film thickness monitoring method and the device thereof capable of suppressing a Joule heat loss to the minimum due to an eddy current, and precisely forecasting and detecting the polishing endpoint, and moreover, precisely calculating a remaining film amount to be removed and a polishing rate and the like on the spot so as to be able to accurately evaluate whether the predetermined conductive film is appropriately removed.
    Type: Application
    Filed: October 18, 2007
    Publication date: November 27, 2008
    Inventors: Takashi Fujita, Toshiyuki Yokoyama, Keita Kitade
  • Publication number: 20080242197
    Abstract: The present invention aims to provide a wafer polish monitoring method and device for detecting the end point of the polishing of a conductive film with high precision and accuracy by monitoring the variation of the film thickness of the conductive film without adverse influence of slurry or the like after the film thickness of the conductive film decreases to an extremely small film thickness defined by the skin depth.
    Type: Application
    Filed: January 10, 2008
    Publication date: October 2, 2008
    Inventors: Takashi Fujita, Toshiyuki Yokoyama, Keita Kitade
  • Publication number: 20080156773
    Abstract: To provide an end point detection method applying a resonance phenomenon, an end point detection apparatus, and a chemical mechanical polishing apparatus on which the detection apparatus is loaded for monitoring variation in the thickness of an electrically conductive film in real time, reliably detecting a polishing end point of the electrically conductive film at high accuracy, without generating noise, low power consumption, and capable of reducing the cost.
    Type: Application
    Filed: September 27, 2007
    Publication date: July 3, 2008
    Inventors: Keita Kitade, Osamu Matsushita, Takashi Fujita, Toshiyuki Yokoyama