Patents by Inventor Motohiro Kouno

Motohiro Kouno 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: 5568252
    Abstract: Reflectance measurement with two monochromatic light beams having different wavelengths is used to obtain curves respective representing the relationship between an insulation film thickness of a semiconductor wafer and the gap between a test electrode and a semiconductor wafer surface. The C-V curve measurement at a fixed gap determines a total capacity of the gap and the insulation film, and a straight line representing the relationship between the gap and the insulation film thickness is obtained from the total capacity. An intersection where the two curves and the straight line cross gives the true values of the gap and the insulation film thickness.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: October 22, 1996
    Assignee: Dainippon Screen Manufacturing Co., Ltd.
    Inventors: Tatsufumi Kusuda, Motohiro Kouno, Ikuyoshi Nakatani, Sadao Hirae
  • Patent number: 5554939
    Abstract: The present invention provides a novel sensor preferably used for non-destructive measurement of the electrical characteristics of semiconductors. The sensor is easily manufactured and has a sufficiently high dielectric breakdown strength. The sensor includes an electrode mount 64 having a an electrode pattern 200 formed on a bottom surface 66a of a cone glass 66. The bottom surface 66a has a reflecting plane 66c for reflecting a laser beam, a test electrode 201, and three parallelism adjustor electrodes 111 through 113 formed around the reflecting plane 66c. The bottom surface 66a also has a guard ring 120 disposed between the test electrode 201 and the parallelism adjustor electrodes 111 through 113. An insulating film 68 covers a lower surface of the cone glass 66. Wiring formed on a inclined face 66b of the cone glass 66 is connected to external lead wires at the upper end of the wiring.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: September 10, 1996
    Assignee: Dainippon Screen Manufacturing Co., Ltd.
    Inventors: Sadao Hirae, Hideaki Matsubara, Motohiro Kouno, Takamasa Sakai
  • Patent number: 5475319
    Abstract: Amounts of electric charges in a semiconductor wafer are measured by using a non-destructive measuring device. First and second flat-band voltages before and after a specific charging process are measured with a non-destructive C-V measurement device. A gap between a test electrode and a surface of a semiconductor wafer is also measured before and after performing the charging process. The electric charge accumulated proximate the surface of the semiconductor wafer is determined according to measured values of the gap and the flat-band voltages before and after performing the charging process.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: December 12, 1995
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Sadao Hirae, Motohiro Kouno, Hideaki Matsubara
  • Patent number: 5444389
    Abstract: A capacitor is connected to an insulating film on a semiconductor wafer. A high-frequency voltage with a bias is applied to the series combination of the semiconductor wafer and the capacitor. The bias voltage is changed stepwise, and the change of the total capacitance is measured. The minority carrier lifetime is calculated from the time-dependent change of the total capacitance.
    Type: Grant
    Filed: September 17, 1993
    Date of Patent: August 22, 1995
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Sadao Hirae, Motohiro Kouno, Takamasa Sakai
  • Patent number: 5239183
    Abstract: The invention provides a device which utilizes the tunnel effect occuring upon a condition of geometric total reflection, for measuring a narrow gap and surface unevenness of a specimen with high precision. An optical device 40 includes a semi-conductor laser 42, a photodiode 43, and a waveguide layer 44 is formed on a semi-conductor substrate 41 by epitaxial growth. A reflecting surface 44b of the waveguide layer 44 is parallel to the plane of the semi-conductor substrate. A laser beam emitted from the semi-conductor laser is reflected from the reflecting surface 44b under a condition of total reflection in geometrical optics. When the gap between the reflecting surface and the specimen is less than or equal to about the wavelength of the laser beam, part of the laser beam is transmitted into the specimen. The intensity of the transmitted light, which is calculated corresponding to the intensity of the reflected light, depends on the dimension of the gap.
    Type: Grant
    Filed: April 16, 1992
    Date of Patent: August 24, 1993
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Motohiro Kouno, Ikuyoshi Nakatani, Takamasa Sakai, Sadao Hirae
  • Patent number: 5233291
    Abstract: A method of measuring C-V characteristics of a semiconductor wafer without forming an electrode on an oxide film thereof. An electrode 201 for C-V measurement is held above a semiconductor wafer 100 across a gap Ge of 1 micrometer or less, and a total capacity including that of the gap Ge is detected. The gap Ge is measured by utilizing the tunneling effect observed in total reflection of light wave. Parallelism of the electrode 201 to the wafer is adjusted by measuring the width of the gap or measuring the capacity of the gap at three different locations on the periphery of the electrode 201.
    Type: Grant
    Filed: September 20, 1991
    Date of Patent: August 3, 1993
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Motohiro Kouno, Ikuyoshi Nakatani, Takamasa Sakai
  • Patent number: 5225690
    Abstract: A narrow gap or unevenness of a surface of a specimen is measured by utilizing the tunnel effect of a light wave reflected at a boundary plane on the condition of total reflection. A laser beam emitted from a laser source is reflected at a surface of a prism on the condition of total reflection in terms of geometrical optics. If a gap between the surface of the prism and the specimen is about the wavelength of the laser beam, part of the laser beam is transmitted into the specimen, and the intensity of the transmitted beam depends on the gap width. A portion of the laser beam is reflected at the boundary plane back into the prism. Therefore, the gap can be measured by measuring the transmittance of the laser beam and comparing the same with the calculated relation between the transmittance and the gap calculated in advance.
    Type: Grant
    Filed: May 29, 1991
    Date of Patent: July 6, 1993
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Takamasa Sakai, Motohiro Kouno, Sadao Hirae, Ikuyoshi Nakatani