Patents by Inventor Katsuhiko Mitani

Katsuhiko Mitani 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).

  • Publication number: 20060183057
    Abstract: Formation of a photomask in the conventional art requires significant cost and time. The invention provides a patterning method of forming a desired latent image pattern by irradiating a resist film formed on a substrate with focused light beam. The method comprising adjusting intensity of the focused light beam or size thereof on the resist film depending on a design of the pattern to irradiate the resist film, thereby achieving a desired pattern with reasonable cost and time.
    Type: Application
    Filed: February 11, 2005
    Publication date: August 17, 2006
    Inventors: Katsuhiko Mitani, Hiroshi Fukuda
  • Publication number: 20060144518
    Abstract: A plasma processing apparatus includes a vacuum processing chamber having a pair of opposing electrodes for plasma generation, one electrode serving as a sample table for a sample including an insulator film. An electrostatic adsorption film is arranged at the sample table electrode to supply a thermal conductive gas between the film and the sample rear surface. A pressure reducing element is also provided. In addition, arrangements are provided to set a gas pressure within said vacuum processing chamber to 0.5 to 4.0 Pa and to apply a high frequency power of 30 MHz to 200 MHz between the electrodes. An electrode cover is disposed at the other electrode, and a clearance between the electrodes is 30 mm to 100 mm.
    Type: Application
    Filed: March 3, 2006
    Publication date: July 6, 2006
    Inventors: Tetsunori Kaji, Shinichi Tachi, Toru Otsubo, Katsuya Watanabe, Katsuhiko Mitani, Junichi Tanaka
  • Patent number: 6902683
    Abstract: A method of plasma-processing is provided which includes placing a sample on one of electrodes provided in a vacuum processing chamber and holding the sample onto the electrodes by an electrostatic attracting force. A processing gas is introduced into an environment in which said sample is placed, and the environment is evacuated to a pressure condition for processing said sample. The processing gas is then formed into a plasma under the pressure condition, the sample is processed by the plasma, and a pulse bias voltage having a pulse cycle of 0.1 ?m to 10 ?m is applied to the sample.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: June 7, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Tetsunori Kaji, Shinichi Tachi, Toru Otsubo, Katsuya Watanabe, Katsuhiko Mitani, Junichi Tanaka
  • Publication number: 20050082006
    Abstract: A plasma processing apparatus includes a vacuum processing chamber having a pair of opposing electrodes for plasma generation, one electrode serving as a sample table for a sample including an insulator film. An electrostatic adsorption film is arranged at the sample table electrode to supply a thermal conductive gas between the film and the sample rear surface. A pressure reducing element is also provided. In addition, arrangements are provided to set a gas pressure within said vacuum processing chamber to 0.5 to 4.0 Pa and to apply a high frequency power of 30 MHz to 200 MHz between the electrodes. An electrode cover s disposed at the other electrode, and a clearance between the electrodes is 30 mm to 100 mm.
    Type: Application
    Filed: November 10, 2004
    Publication date: April 21, 2005
    Inventors: Tetsunori Kaji, Shinichi Tachi, Toru Otsubo, Katsuya Watanabe, Katsuhiko Mitani, Junichi Tanaka
  • Publication number: 20040178180
    Abstract: A plasma processing apparatus includes a vacuum processing chamber having a pair of opposing electrodes for plasma generation, one electrode serving as a sample table for a sample including an insulator film. An electrostatic adsorption film is arranged at the sample table electrode to supply a thermal conductive gas between the film and the sample rear surface. A pressure reducing element is also provided. In addition, arrangements are provided to set a gas pressure within said vacuum processing chamber to 0.5 to 4.0 Pa and to apply a high frequency power of 30 MHz to 200 MHz between the electrodes. An electrode cover is disposed at the other electrode, and a clearance between the electrodes is 30 mm to 100 mm.
    Type: Application
    Filed: March 25, 2004
    Publication date: September 16, 2004
    Inventors: Tetsunori Kaji, Shinichi Tachi, Toru Otsubo, Katsuya Watanabe, Katsuhiko Mitani, Junichi Tanaka
  • Publication number: 20020069971
    Abstract: A plasma processing apparatus and a plasma processing method are provided. The plasma processing apparatus and a plasma processing method are capable of easily performing precise working of a fine pattern to a large sized sample having a diameter of 300 mm or larger, and also capable of improving a selectivity during micro processing.
    Type: Application
    Filed: January 23, 2002
    Publication date: June 13, 2002
    Inventors: Tetsunori Kaji, Shinichi Tachi, Toru Otsubo, Katsuya Watanabe, Katsuhiko Mitani, Junichi Tanaka
  • Patent number: 6245190
    Abstract: A plasma processing apparatus and a method therefor which can achieve a preferred process rate, a fine pattern process capability, a selectivity and uniformity of processing at the same time compatibly for a large size wafer, which effects are achieved by controlling the plasma state and the dissociation state of etching gas through control of the electron resonance through application of a magnetic field thereto. A high frequency power at 20-300 MHz is applied across a pair of electrodes in a vacuum process chamber, and a magnetic field is formed parallel to the plane of the electrodes in the space between the electrodes. By controlling the intensity of the magnetic field in a range of 100 gauss or smaller, formation of electron cyclotron resonance and electron sheath resonance occurring from interaction between the electrical field and the magnetic field in the electrode sheath portion is controlled. Thereby, the plasma state, i.e.
    Type: Grant
    Filed: March 26, 1998
    Date of Patent: June 12, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Toshio Masuda, Katsuhiko Mitani, Tetsunori Kaji, Jun'ichi Tanaka, Katsuya Watanabe, Shigeru Shirayone, Toru Otsubo, Ichiro Sasaki, Hideshi Fukumoto, Makoto Koizumi
  • Patent number: 6197151
    Abstract: A plasma processing apparatus comprising a vacuum processing chamber, a plasma generating means including a pair of electrodes, a sample table for mounting a sample to be processed inside the vacuum processing chamber and also serving as one of the electrodes, and a evacuating means for evacuating the vacuum processing chamber, which further comprises a high frequency electric power source for applying an electric power of a VHF band from 50 MHz to 200 MHz between the pair of electrodes; and a magnetic field forming means for forming a static magnetic field or a low frequency magnetic field larger than 10 gausses and smaller than 110 gausses in a direction intersecting an electric field generated between the pair of electrodes and the vicinity by the high frequency electric power source; therein the magnetic field forming means being set so that a portion where a component of the magnetic field in a direction along the surface of the sample table becomes maximum is brought to a position in the opposite side o
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: March 6, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Tetsunori Kaji, Shinichi Tachi, Toru Otsubo, Katsuya Watanabe, Katsuhiko Mitani, Junichi Tanaka
  • Patent number: 6129806
    Abstract: A plasma processing apparatus and method are provided which are capable of easily performing precise working of a fine pattern on a large sized sample having a diameter of 300 mm or larger, and also capable of improving selectivity during micro processing. The apparatus includes a vacuum processing chamber, a plasma generating arrangement including a pair of electrodes, a sample table for mounting a sample to be processed inside the vacuum processing chamber and also serving as one of the electrodes, and an evacuating means for evacuating the vacuum processing chamber. The apparatus further includes a high frequency electric power source for applying an electric power of VHF band from 50 MHz to 200 MHz between the pair of electrodes.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: October 10, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Tetsunori Kaji, Shinichi Tachi, Toru Otsubo, Katsuya Watanabe, Katsuhiko Mitani, Junichi Tanaka
  • Patent number: 5668402
    Abstract: A semiconductor device comprises a semiconductor substrate formed by a first single crystalline semiconductor material and semiconductor layers formed on the semiconductor substrate by a second single crystalline semiconductor material doped with an element which can easily surface segregate. The surface of the semiconductor substrate is formed of a crystalline plane substantially equivalent to a facet plane which is formed on the surface of the second single crystalline semiconductor material if the second single crystalline semiconductor material is epitaxially grown with being doped with the element on a (100) plane of the first single crystalline semiconductor material.
    Type: Grant
    Filed: May 24, 1993
    Date of Patent: September 16, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiro Mochizuki, Shigeo Goto, Chushirou Kusano, Masahiko Kawata, Hiroshi Masuda, Katsuhiko Mitani, Susumu Takahashi
  • Patent number: 5401357
    Abstract: A method may be used to dry etch a sample including a plurality of regions different from each other in the photo-absorption of a light having a specified wavelength using an etching gas plasma. The method is capable of selectively etching the desired material from a plurality of materials having different types of band gap energies or from a plurality of materials having different band gap energies. The method includes a step of irradiating a light having the specified wavelength on the sample for reducing an etching rate of a region having a large photo-absorption coefficient to the light, thereby selectively etching a region having a small photo-absorption coefficient to the light.
    Type: Grant
    Filed: September 1, 1992
    Date of Patent: March 28, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Hidekazu Okuhira, Tetsuo Ono, Susumu Hiraoka, Keizo Suzuki, Junji Shigeta, Hiroshi Masuda, Mitsuhiro Mori, Takuma Tanimoto, Shinichi Nakatsuka, Katsuhiko Mitani
  • Patent number: 5381027
    Abstract: This invention discloses a heterojunction type field effect transistor such as 2DEG-FET and a heterojunction type bipolar transistor such as 2DEG-HBT. The former is fabricated by applying to the formation of its source and drain regions a technique which causes the disorder of the heterojunction by intoduction of an impurity such as by ion implantation or a technique which causes the disorder of the heterojunction by forming a film made of at least one kind of material selected from insulators, metals and semiconductors which have a different linear coefficient of thermal expansion from that of the material of a semiconductor substrate on the heterojunction semiconductor region which is to be disordered. The latter is fabricated by applying either of the techniques described above to a base ohmic contact region. These semiconductor devices can reduce the source-gate resistance and the parasitic base resistance.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: January 10, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Usagawa, Kenji Hiruma, Masahiko Kawata, Shigeo Goto, Katsuhiko Mitani, Masao Yamane, Susumu Takahashi, Tomonori Tanoue, Yoshinori Imamura
  • Patent number: 5296733
    Abstract: A hetero junction bipolar transistor provides a contact area an area between an emitter (or collector) electrode and a wiring formed on the electrode that is larger than that of the emitter (or collector). A variation in voltage applied to an emitter (or collector)-base junctions is prevented and a stable operation of the transistor is attained. In addition, when an etching operation is carried out, an insulation film is formed on a side part of a mask. A patterning of the emitter (or collector) is then carried out and thus an emitter (or collector) having a size approximate to that of the mask is formed.
    Type: Grant
    Filed: November 19, 1990
    Date of Patent: March 22, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Chushiroh Kusano, Hiroshi Masuda, Katsuhiko Mitani, Kazuhiro Mochizuki, Masaru Miyazaki, Masahiko Kawata, Susumu Takahashi
  • Patent number: 5258631
    Abstract: This invention discloses a heterojunction type field effect transistor such as 2DEG-FET and a heterojunction type bipolar transistor such as 2DEG-HBT. The former is fabricated by applying to the formation of its source and drain regions a technique which causes the disorder of the heterojunction by introduction of an impurity such as by ion implantation or a technique which causes the disorder of the heterojunction by forming a film made of at least one kind of material selected from insulators, metals and semiconductors which have a different linear coefficient of thermal expansion from that of the material of a semiconductor substrate on the heterojunction semiconductor region which is to be disordered. The latter is fabricated by applying either of the techniques described above to a base ohmic contact region. These semiconductor devices can reduce the source-gate resistance and the parasitic base resistance.
    Type: Grant
    Filed: May 18, 1992
    Date of Patent: November 2, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Usagawa, Kenji Hiruma, Masahiko Kawata, Shigeo Goto, Katsuhiko Mitani, Masao Yamane, Susumu Takahashi, Tomonori Tanoue, Yoshinori Imamura
  • Patent number: 5019524
    Abstract: Disclosed is a semiconductor device including a heterojunction bipolar transistor in which the front surface of a base layer and the surface of an emitter-base junction are covered with a high-resistivity layer of compound semiconductor containing at least one constituent element common to an emitter layer and the base layer.
    Type: Grant
    Filed: August 30, 1989
    Date of Patent: May 28, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiko Mitani, Tomonori Tanoue, Chushiro Kusano, Masayoshi Kobayashi, Susumu Takahashi
  • Patent number: 5017517
    Abstract: A method for fabricating a semiconductor device comprises the steps of forming the first semiconductor layer on a semiconductor substrate, forming a surface protection layer of antimony (Sb) or the material having Sb as its main component, executing the other steps necessary for the fabrication of the semiconductor device, removing the surface protection layer, and forming, on the first semiconductor layer thus exposed, the second semiconductor layer.
    Type: Grant
    Filed: May 2, 1990
    Date of Patent: May 21, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiro Mochizuki, Tomonori Tanoue, Chushirou Kusano, Hiroshi Masuda, Katsuhiko Mitani
  • Patent number: 4983532
    Abstract: Microfabrication and large scale integration of a device can be realized by using a planar heterojunction bipolar transistor formed by a process comprising successively growing semiconductor layers serving as a subcollector, a collector, a base, and an emitter, respectively, through epitaxial growth on a compound semiconductor substrate in such a manner that at least one of the emitter junction and collector junction is a heterojunction, wherein a collector drawing-out metal layer is formed by the selective CVD method.
    Type: Grant
    Filed: December 20, 1988
    Date of Patent: January 8, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiko Mitani, Tomonori Tanoue, Chushirou Kusano, Susumu Takahashi, Masayoshi Saito, Hiroshi Miyazaki, Fumio Murai
  • Patent number: 4979009
    Abstract: 2A heterojunction bipolar transistor is disclosed in which a region of a base layer which extends in the vicinity of the interface between the base layer and an emitter layer is doped with an impurity at a higher concentration than that in the inside of the base layer to thereby form a built-in field by which carriers injected from the emitter are caused to drift to the inside of the base layer. In the transistor having this structure, the current gain does not depend on the emitter area, and it is possible to obtain a large current gain with a small emitter area.
    Type: Grant
    Filed: September 29, 1989
    Date of Patent: December 18, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Chushiro Kusano, Tomonori Tanoue, Katsuhiko Mitani