Patents by Inventor Sachio Ishioka

Sachio Ishioka 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: 5233265
    Abstract: A photoconductive device having a photoconductive layer which includes an amorphous semiconductor layer capable of charge multiplication in at least a part thereof is disclosed. The method of operating such a photoconductive device is also disclosed. By using the avalanche effect of the amorphous semiconductor layer, it is possible to realize a highly sensitive photoconductive device while maintaining low lag property. In one aspect of the present invention, the amorphous semiconductor layer is amorphous Se. In another aspect of the present invention, the amorphous semiconductor layer is composed mainly of tetrahedral elements including at least an element of hydrogen or halogens. When using the amorphous semiconductor layer composed mainly of tetrahedral elements, the charge multiplication effect is produced mainly in the interior of the amorphous semiconductor, and thus it is possible to obtain a thermally stable photoconductive device having a high sensitivity while keeping a good photoresponse.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: August 3, 1993
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Yukio Takasaki, Kazutaka Tsuji, Tatsuo Makishima, Tadaaki Hirai, Sachio Ishioka, Tatsuro Kawamura, Keiichi Shidara, Eikyu Hiruma, Kenkichi Tanioka, Junichi Yamazaki, Kenji Sameshima, Hirokazu Matsubara, Kazuhisa Taketoshi, Mitsuo Kosugi, Shiro Suzuki, Takashi Yamashita, Masaaki Aiba, Yoshizumi Ikeda, Tsuyoshi Uda, Naohiro Goto, Yasuhiko Nonaka, Eisuke Inoue, Hirofumi Ogawa
  • Patent number: 5101255
    Abstract: Disclosed is a photoelectric conversion device which comprises: a photoconductive layer made of amorphous semiconductor material which shows charge multiplication and which converts photo signals into electric signals; and a substrate having electric circuits or the like (for example switching elements) for reading the electric signals. The amorphous semiconductor material used according to the invention shows the charge multiplication action under predetermined intensity of electric field so that a high sensitive photoelectric conversion device having a gain which is not smaller than 1 is realized.
    Type: Grant
    Filed: July 24, 1989
    Date of Patent: March 31, 1992
    Inventors: Sachio Ishioka, Yukio Takasaki, Tadaaki Hirai, Kazutaka Tsuji, Tatsuo Makishima, Yasuhiko Nonaka, Tatsuro Kawamura, Takashi Yamashita, Kazuhisa Taketoshi, Keiichi Shidara, Fumihiko Ando, Kenkichi Tanioka
  • Patent number: 4980736
    Abstract: A photoelectric conversion device using an amorphous material composed mainly of tetrahedral elements including at least an element of hydrogen and halogens as semiconductor material is disclosed. When a strong electric field is applied to a layer formed by using this amorphous semiconductor, a charge multiplication effect is produced mainly in the interior of the amorphous semiconductor and thus it is possible to obtain a thermally stable photoelectric conversion device having a high sensitivity while keeping a good photoresponse.
    Type: Grant
    Filed: February 16, 1988
    Date of Patent: December 25, 1990
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Yukio Takasaki, Kazutaka Tsuji, Tatsuo Makishima, Tadaaki Hirai, Sachio Ishioka, Tatsuro Kawamura, Keiichi Shidara, Eikyu Hiruma, Kenkichi Tanioka, Junichi Yamazaki, Kenji Sameshima, Hirokazu Matsubara, Kazuhisa Taketoshi
  • Patent number: 4952839
    Abstract: A photoconductive device having a photoconductive layer which includes an amorphous semiconductor layer capable of charge multiplication in at least a part thereof is disclosed. The method of operating such a photoconductive device is also disclosed. By using the avalanche effect of the amorphous semiconductor layer, it is possible to realize a highly sensitive photoconductive device while maintaining low lag property.
    Type: Grant
    Filed: October 12, 1989
    Date of Patent: August 28, 1990
    Assignees: Hitachi, Ltd, Nippon Hoso Kyokai
    Inventors: Kenkichi Tanioka, Mitsuo Kosugi, Junichi Yamazaki, Keiichi Shidara, Kazuhisa Taketoshi, Tatsuro Kawamura, Eikyuu Hiruma, Shiro Suzuki, Takashi Yamashita, Masaaki Aiba, Yochizumi Ikeda, Tadaaki Hirai, Yukio Takasaki, Sachio Ishioka, Tatsuo Makishima, Kenji Sameshima, Tsuyoshi Uda, Naohiro Goto, Yasuhiko Nonaka, Eisuke Inoue, Kazutaka Tsuji, Hirofumi Ogawa
  • Patent number: 4900975
    Abstract: A target of an image pickup tube is formed by laminating at least a transparent conductive film, an amorphous layer consisting essentially of silicon, and an amorphous layer consisting essentially of selenium in the above order on a light-transmitting substrate.
    Type: Grant
    Filed: June 29, 1987
    Date of Patent: February 13, 1990
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Yasuharu Shimomoto, Sachio Ishioka, Yukio Takasaki, Tadaaki Hirai, Kazutaka Tsuji, Tatsuo Makishima, Hirokazu Matsubara, Kenji Sameshima, Junichi Yamazaki, Kenkichi Tanioka, Mitsuo Kosugi, Keiichi Shidara, Tatsuro Kawamura, Eikyuu Hiruma, Takashi Yamashita
  • Patent number: 4888521
    Abstract: A photoconductive device having a photoconductive layer which includes an amorphous semiconductor layer capable of charge multiplication in at least a part thereof is disclosed. The method of operating such a photoconductive device is also disclosed. By using the avalanche effect of the amorphous semiconductor layer, it is possible to realize a highly sensitive photoconductive device while maintaining low lag property.
    Type: Grant
    Filed: July 2, 1987
    Date of Patent: December 19, 1989
    Assignees: Hitachi Ltd., Nippon Hoso Kyokai
    Inventors: Kenkichi Tanioka, Keiichi Shidara, Tatsuro Kawamura, Junichi Yamazaki, Eikyuu Hiruma, Kazuhisa Taketoshi, Shiro Suzuki, Takashi Yamashita, Mitsuo Kosugi, Yochizumi Ikeda, Masaaki Aiba, Tadaaki Hirai, Yukio Takasaki, Sachio Ishioka, Tatsuo Makishima, Kenji Sameshima, Tsuyoshi Uda, Naohiro Goto, Yasuhiko Nonaka, Eisuke Inoue, Kazutaka Tsuji, Hirofumi Ogawa
  • Patent number: 4884011
    Abstract: A light-detecting device for converting a light to an electrical signal utilizes a charge multiplication function and has a stable gain.The light-detecting device comprises a photo-electric conversion unit for converting a measurement light to an electrical signal, a power supply for applying an electric field to the photo-electric conversion unit, a light source for applying an incident light to the photo-electric conversion unit, signal detection means for detecting the charge converted by the photo-electric conversion unit based on the incident light from the light source, and signal hold means for holding the output signal of the signal detection means at a predetermined level.
    Type: Grant
    Filed: January 13, 1988
    Date of Patent: November 28, 1989
    Assignee: Hitachi, Ltd. & Nippon Hoso Kasai
    Inventors: Tatsuo Makishima, Tadaaki Hirai, Kazutaka Tsuji, Sachio Ishioka, Takashi Yamashita, Keiichi Shidara, Junichi Yamazaki, Masaaki Aiba
  • Patent number: 4829345
    Abstract: Within an electronic device having a plurality of circuit parts (such as a three-dimensional device), a light transmission system which transfers signals between the circuit parts by the use of light is provided.The light transmission system is formed of a light emitting source which emits light having a desired wavelength, a photoelectric conversion portion which absorbs the light and converts it into an electric signal, and a light traveling path which conveys the light emitted from the light emitting source to the photoelectric conversion portion.Further, each of the light emitting source, the light traveling path and the photoelectric conversion portion is formed of a superlattice structure in which a plurality of materials of unequal energy gaps are layered.
    Type: Grant
    Filed: April 29, 1986
    Date of Patent: May 9, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Sachio Ishioka, Kazutaka Tsuji, Yukio Takasaki, Yasuharu Shimomoto, Hirokazu Matsubara, Tadaaki Hirai
  • Patent number: 4636682
    Abstract: A high velocity electron beam scanning negatively charge biased image pickup tube has a target which includes at least a transparent conductive layer, a photoconductor layer and a layer for secondary electron emission on a light-transmissive insulating substrate, and in which the transparent conductive layer is arranged on a light incidence side, the photoconductor layer being made of amorphous silicon.
    Type: Grant
    Filed: May 5, 1983
    Date of Patent: January 13, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Chushirou Kusano, Sachio Ishioka, Yoshinori Imamura, Yukio Takasaki, Hirofumi Ogawa, Tatsuo Makishima, Tadaaki Hirai
  • Patent number: 4626885
    Abstract: A photosensor including a transparent electrode for transmitting incident light and a photoconductive layer receiving light from the transparent electrode for performing photoelectric conversion, is disclosed in which the photoconductive layer is made of amorphous silicon, the amorphous silicon contains 5 to 30 atomic percent hydrogen and is doped with at least one selected from elements belonging to the groups II and III in such a manner that a region remote from the transparent electrode is higher in the concentration of the selected element than another region proximate to the transparent electrode, and a voltage is applied across the photoconductive layer so that a surface of the photoconductive layer facing the transparent electrode is at a positive potential with respect to another surface of the photoconductive layer opposite to the surface facing the transparent electrode.
    Type: Grant
    Filed: July 29, 1983
    Date of Patent: December 2, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Sachio Ishioka, Yoshinori Imamura, Tsuyoshi Uda, Yukio Takasaki, Chushirou Kusano, Hirofumi Ogawa, Tatsuo Makishima, Tadaaki Hirai
  • Patent number: 4609846
    Abstract: An image pick-up tube has a photoelectric conversion target including a transparent substrate, and a transparent electrode and a photoconductive layer formed on the transparent substrate. An electron beam is scanned on the photoelectric conversion target. A first electrode is formed on a beam scanning surface of the photoconductive layer so as to be segmented in stripe or grid with its electrode segments electrically connected to each other. A second electrode is formed on the first electrode through an insulating layer with its electrode segments electrically connected to each other. An insulating layer may be interposed between the first electrode and the photoconductive layer.
    Type: Grant
    Filed: September 20, 1984
    Date of Patent: September 2, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Chushirou Kusano, Sachio Ishioka, Yasuharu Shimomoto, Yoshinori Imamura, Hirofumi Ogawa
  • Patent number: 4564784
    Abstract: An image pickup tube comprising a target composed of a light-transmissible plate, a transparent electrode provided on said light-transmissible plate and a photoconductor made of hydrogen-containing amorphous silicon provided on said transparent electrode; an electron beam generator; and a mesh electrode near the aforesaid target, at least the surface of said mesh electrode being made of at least one member selected from the group consisting of Be, B, C, Mg, Al and Si, has high resolution with greatly improved life characteristics.
    Type: Grant
    Filed: November 16, 1983
    Date of Patent: January 14, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Sachio Ishioka, Yoshinori Imamura, Tadaaki Hirai, Saburo Nobutoki, Akio Maruyama
  • Patent number: 4556817
    Abstract: An image pickup tube of high velocity electron beam scanning and negatively charging system having a target including, on a transparent substrate, at least a transparent conductive film, a photoconductive layer, a layer for emitting secondary electrons, and stripe electrodes. The transparent substrate may be made of amorphous silicon.
    Type: Grant
    Filed: November 2, 1983
    Date of Patent: December 3, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Chushirou Kusano, Sachio Ishioka, Yoshinori Imamura, Yukio Takasaki, Hirofumi Ogawa, Tatsuo Makishima, Tadaaki Hirai, Eiichi Maruyama
  • Patent number: 4554478
    Abstract: In a photoelectric conversion element including at least a first electrode and a photoconductive layer having an amorphous material whose indispensable constituent is silicon and which contains hydrogen as an essential constituent element on a predetermined substrate, the present invention discloses a photoelectric conversion element wherein said layer of the amorphous material is disposed on said first electrode via a light transmitting or light semi-transmitting metallic layer for adhesion with respect to said amorphous material. As said metallic layer for adhesion, preferred is a layer consisting of at least one metal selected from the group consisting of Ta, Cr, W, Nd, Mo, V and Ti. Thus, adhesion between said substrate and said amorphous material can be improved.
    Type: Grant
    Filed: May 25, 1983
    Date of Patent: November 19, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Yasuharu Shimomoto, Yasuo Tanaka, Yukio Takasaki, Sachio Ishioka, Toshihisa Tsukada, Toru Baji
  • Patent number: 4419604
    Abstract: Disclosed is a light sensitive screen including at least a light-transmitting conductive film and a photoconductive layer, the light-transmitting conductive film being arranged on a side of incidence of light, characterized in that the photoconductive layer is constructed of a single layer or a plurality of layers of one or more photoconductive substances, at least one of such photoconductive substance layers being formed of an amorphous silicon material which contains at least 5 atomic-% to 30 atomic-% of hydrogen, whose optical forbidden band gap is 1.65 eV to 2.25 eV and whose peak component in an infrared absorption spectrum at a wave number of 2,100 cm.sup.-1 is greater than that at a wave number of 2,000 cm.sup.-1. Various characteristics of an imaging device provided with the light sensitive screen, such as dark current, lag and after image characteristics, are improved.
    Type: Grant
    Filed: April 24, 1981
    Date of Patent: December 6, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Sachio Ishioka, Yoshinori Imamura, Yasuharu Shimomoto, Saburo Ataka, Yasuo Tanaka, Eiichi Maruyama
  • Patent number: 4394749
    Abstract: A photoelectric device having at least a predetermined impurity region which is disposed in a semiconductor substrate, and a photoelectric conversion portion which is constructed by stacking an electrode layer lying in contact with at least a part of the impurity region, a photoconductive material layer overlying the electrode layer, and a transparent electrode overlying the photoconductive material layer, characterized in that the photoconductive material layer is made of an amorphous chalcogenide material which principally contains Se, is disclosed. It is very favorable that the photoelectric conversion material layer made of the amorphous material principally containing Se is partially doped with Te so as to enhance its sensitivity. The amorphous chalcogenide material is very useful in the following point.
    Type: Grant
    Filed: May 30, 1980
    Date of Patent: July 19, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Toshihisa Tsukada, Yukio Takasaki, Tadaaki Hirai, Toru Baji, Hideaki Yamamoto, Yasuo Tanaka, Eiichi Maruyama, Sachio Ishioka
  • Patent number: 4380557
    Abstract: In preparing an image pickup device by using hydrogen-containing amorphous silicon for a photoconductive layer, a hydrogen-containing amorphous silicon layer is first formed and is then heat-treated at 100.degree. to 300.degree. C. The image pickup characteristics of the amorphous silicon layer are highly improved by this heat treatment. For example, the lag and dark current are reduced and the signal current-target voltage characteristic is improved. Especially excellent improving effects can be obtained when amorphous silicon characterized in that (1) the hydrogen content is 5 to 30 atomic %, (2) the optical forbidden band gap is 1.30 to 1.95 eV and (3) in the infrared absorption spectrum, the component of a wave number of 2000 cm.sup.-1 is observed larger than the component of a wave number of 2100 cm.sup.-1 is subjected to the above-mentioned heat treatment. The adhesion to the substrate is enhanced, and good image pickup characteristics can be obtained.
    Type: Grant
    Filed: July 28, 1981
    Date of Patent: April 19, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Sachio Ishioka, Yasuharu Shimomoto, Yoshinori Imamura, Saburo Ataka, Yasuo Tanaka, Hirokazu Matsubara, Yukio Takasaki, Eiichi Maruyama
  • Patent number: 4378417
    Abstract: In an electrophotographic member employing an amorphous silicon photoconductive layer, a part which is at least 10 nm thick inwardly of the amorphous silicon layer from the surface (or interface) of the amorphous silicon layer is made of amorphous silicon which has an optical forbidden band gap of at least 1.6 eV and a resistivity of at least 10.sup.10 .OMEGA..cm. The electrophotographic member exhibits a satisfactory resolution and good dark-decay characteristics. Further, a region which has an optical forbidden band gap narrower than that of the amorphous silicon forming the surface (or interface) region is disposed within the amorphous silicon layer to a thickness of at least 10 nm, whereby the sensitivity of the electrophotographic member to longer wavelengths of light can be enhanced.
    Type: Grant
    Filed: April 15, 1981
    Date of Patent: March 29, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Eiichi Maruyama, Sachio Ishioka, Yoshinori Imamura, Hirokazu Matsubara, Yasuharu Shimomoto, Shinkichi Horigome, Yoshio Taniguchi
  • Patent number: 4377628
    Abstract: Disclosed is an electrophotographic member having an amorphous-silicon photoconductive layer, wherein the distance between a portion in which light illuminating the photoconductor is absorbed therein until its intensity decreases to 1% of that at incidence and the interface of the photoconductor opposite to the light incidence side thereof is at most 5 .mu.m, whereby the residual potential of the photoconductive layer can be reduced.That part of the photoconductive layer constituting the electrophotographic member which is at least 10 nm thick inwardly of the photoconductive layer from the surface thereof to store charges is made of amorphous silicon which has an optical forbidden band gap of at least 1.6 eV and a resistivity of at least 10.sup.10 .OMEGA..multidot.cm. Further, within such photoconductive layer, a region of amorphous silicon which has an optical forbidden band gap smaller than that of the amorphous silicon forming the surface part is disposed at a thickness of at least 10 nm.
    Type: Grant
    Filed: April 24, 1981
    Date of Patent: March 22, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Sachio Ishioka, Eiichi Maruyama, Yoshinori Imamura, Hirokazu Matsubara, Shinkichi Horigome
  • Patent number: RE33094
    Abstract: In an electrophotographic member employing an amorphous silicon photoconductive layer, a part which is at least 10 nm thick inwardly of the amorphous silicon layer from the surface (or interface) of the amorphous silicon layer is made of amorphous silicon which has an optical forbidden band gap of at least 1.6 eV and a resistivity of at least 10.sup.10 .OMEGA..cm. The electrophotographic member exhibits a satisfactory resolution and good dark-decay characteristics. Further, a region which has an optical forbidden band gap narrower than that of the amorphous silicon forming the surface (or interface) region is disposed within the amorphous silicon layer to a thickness of at least 10 nm, whereby the sensitivity of the electrophotographic member to longer wavelengths of light can be enhanced.
    Type: Grant
    Filed: September 11, 1986
    Date of Patent: October 17, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Eiichi Maruyama, Sachio Ishioka, Yoshinori Imamura, Hirokazu Matsubara, Yasuharu Shimomoto, Shinkichi Horigome, Yoshio Taniguchi