Patents by Inventor Hidong Kwak

Hidong Kwak 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: 7295325
    Abstract: In one embodiment, a probe pulse is first stretched into a pulse of longer duration. The probe pulse comprises a plurality of wavelength components in a bandwidth, so that each temporal portion of the converted pulse corresponds to and comprises one of the wavelength components. This converted pulse is supplied to the sample at the time when it is affected by the disturbance of the sample caused by a pump pulse. Changes in characteristics of the sample at the wavelength components of the temporal portions of the converted pulse are then detected after the converted pulse has been modified by the sample. Such changes are then analyzed to derive characteristics of the sample. In another embodiment, a converter passes to a detector radiation from a probe beam that has been modified by the sample during a temporal sequence of time intervals, where the time intervals correspond to displacement in a spatial record.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: November 13, 2007
    Assignee: KLA-Tencor Technologies Corporation
    Inventors: Hidong Kwak, Gary Janik, Mehrdad Nikoonahad
  • Patent number: 7190441
    Abstract: Methods and systems for preparing a sample for thin film analysis are provided. One system includes an energy beam source configured to generate an energy beam. The system also includes an energy beam delivery subsystem configured to direct the energy beam to a sample and to modify the energy beam such that the energy beam has a substantially flat-top profile on the sample. The energy beam removes a portion of a contaminant layer on the sample to expose an analysis area of a thin film on the sample. One method includes generating an energy beam and modifying the energy beam such that the energy beam has a substantially flat-top profile. The method also includes directing the energy beam to a sample. The energy beam removes a portion of a contaminant layer on the sample to expose an analysis area of a thin film on the sample.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: March 13, 2007
    Assignee: KLA-Tencor Technologies Corp.
    Inventors: James T. McWhirter, Liang-Guo Wang, Hidong Kwak, Haixing Zou, Dan Georgesco, Bernard Lautee, Jennming James Chen, Gary R. Janik, Patrick M. Maxton
  • Patent number: 6999180
    Abstract: An apparatus capable of measuring topography and transparent film thickness of a patterned metal-dielectric layer on a substrate without contact with the layer. A broadband interferometer measures an absolute phase of reflection at a plurality of wavelengths from a plurality of locations within a field of view on the metal-dielectric patterned layer on the substrate, and produces reflection phase data. An analyzer receives the reflection phase data and regresses the transparent film thickness and the topography at each of the plurality of locations from the reflection phase data. In this manner, the apparatus is not confused by the phase changes produced in the reflected light by the transparent layers, because the thickness of the transparent layers are determined by using the reflection phase data from multiple wavelengths. Further, the surface topography of the layer, whether it be opaque or transparent is also determinable.
    Type: Grant
    Filed: April 2, 2003
    Date of Patent: February 14, 2006
    Assignee: KLA-Tencor Technologies Corporation
    Inventors: Gary R. Janik, Hidong Kwak, Ying Gao, Johannes D. De Veer
  • Publication number: 20040207850
    Abstract: In one embodiment, a probe pulse is first stretched into a pulse of longer duration. The probe pulse comprises a plurality of wavelength components in a bandwidth, so that each temporal portion of the converted pulse corresponds to and comprises one of the wavelength components. This converted pulse is supplied to the sample at the time when it is affected by the disturbance of the sample caused by a pump pulse. Changes in characteristics of the sample at the wavelength components of the temporal portions of the converted pulse are then detected after the converted pulse has been modified by the sample. Such changes are then analyzed to derive characteristics of the sample. In another embodiment, a converter passes to a detector radiation from a probe beam that has been modified by the sample during a temporal sequence of time intervals, where the time intervals correspond to displacement in a spatial record.
    Type: Application
    Filed: September 26, 2003
    Publication date: October 21, 2004
    Inventors: Hidong Kwak, Gary Janik, Mehrdad Nikoonahad
  • Publication number: 20040150820
    Abstract: In an optical system measuring sample characteristics, by reducing the amount of ambient absorbing gas or gases and moisture present in at least a portion of the illumination and detection paths experienced by vacuum ultraviolet (VUV) radiation used in the measurement process, the attenuation of such wavelength components can be reduced. Such reduction can be accomplished by a process without requiring the evacuation of all gases and moisture from the measurement system. In one embodiment, the reduction can be accomplished by displacing at least some of the absorbing gas(es) and moisture present in at least a portion of the measuring paths so as to reduce the attenuation of VUV radiation. In this manner, the sample does not need to be placed in a vacuum, thereby enhancing system throughput.
    Type: Application
    Filed: November 19, 2003
    Publication date: August 5, 2004
    Inventors: Mehrdad Nikoonahad, Shing Lee, Hidong Kwak, Sergio Edelstein, Guoheng Zhao, Gary Janik