Patents by Inventor Yuko Tawada

Yuko Tawada 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: 9166080
    Abstract: Disclosed are: a transparent electrode having a zinc oxide film wherein initial characteristics and humidity resistance during long-time use coexist; and a thin film solar cell provided with said electrode. The transparent electrode contains a transparent conductive layer mainly made of zinc oxide. The transparent conductive film preferably has the following characteristics: having surface irregularities; a carrier concentration of 9×1019 cm?3 or less; a crystal structure having a (110) preferred orientation; a ratio of a (110) peak intensity to a (002) peak intensity I(110)/I(002) measured by X-ray diffraction being 50 or more; and a crystallite with a (110) orientation has a size of: 23 nm or more and 50 nm or less, in a planar direction parallel to a substrate; and 30 nm or more and 60 nm or less, in a planar direction perpendicular to the substrate.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: October 20, 2015
    Assignee: KANEKA CORPORATION
    Inventors: Yuko Tawada, Takashi Fujibayashi
  • Patent number: 8907204
    Abstract: Provided is a thin film photoelectric conversion device with maximized output characteristic, which is achieved by improving an uneven current value of a photoelectric conversion cell caused by an uneven film thickness and an uneven film quality of a photoelectric conversion semiconductor layer, which may be generated in scaling up an integrated-type thin film photoelectric conversion device. The thin film photoelectric conversion device includes: a substrate, a transparent electrode layer, a photoelectric conversion unit, and a back electrode layer. An increasing rate ?Zt of the film thickness Zt of the transparent electrode layer along X and an increasing rate ?Zs of the film thickness Zs of the photoelectric conversion unit along X have different signs, wherein one line segment in a parallel direction to a main surface of the substrate is taken as X?.
    Type: Grant
    Filed: May 19, 2009
    Date of Patent: December 9, 2014
    Assignee: Kaneka Corporation
    Inventors: Takashi Fujibayashi, Toshiaki Sasaki, Yuko Tawada
  • Patent number: 8658887
    Abstract: Provided in this invention is a low-cost substrate provided with a transparent conductive film for photoelectric conversion device, which can improve performance of the photoelectric conversion device by enhanced light confinement effect achieved with effectively increased surface unevenness of the substrate. A method for manufacturing said substrate and a photoelectric conversion device using said substrate which can show improved performance are also provided. The substrate provided with the transparent conductive film for the photoelectric conversion device comprises a transparent insulating substrate and a transparent electrode layer containing at least zinc oxide deposited on the transparent insulating substrate, wherein the transparent electrode layer is composed of a double layer structure wherein first and second transparent conductive films are deposited in this order from a substrate side.
    Type: Grant
    Filed: November 12, 2007
    Date of Patent: February 25, 2014
    Assignee: Kaneka Corporation
    Inventor: Yuko Tawada
  • Publication number: 20130118580
    Abstract: Disclosed are: a transparent electrode having a zinc oxide film wherein initial characteristics and humidity resistance during long-time use coexist; and a thin film solar cell provided with said electrode. The transparent electrode contains a transparent conductive layer mainly made of zinc oxide. The transparent conductive film preferably has the following characteristics: having surface irregularities; a carrier concentration of 9×1019 cm?3 or less; a crystal structure having a (110) preferred orientation; a ratio of a (110) peak intensity to a (002) peak intensity I(110)/I(002) measured by X-ray diffraction being 50 or more; and a crystallite with a (110) orientation has a size of: 23 nm or more and 50 nm or less, in a planar direction parallel to a substrate; and 30 nm or more and 60 nm or less, in a planar direction perpendicular to the substrate.
    Type: Application
    Filed: June 7, 2011
    Publication date: May 16, 2013
    Applicant: KANEKA CORPORATION
    Inventors: Yuko Tawada, Takashi Fujibayashi
  • Publication number: 20110061715
    Abstract: Provided is a thin film photoelectric conversion device with maximized output characteristic, by improving an uneven current value of a photoelectric conversion cell caused by an uneven film thickness and an uneven film quality of a photoelectric conversion semiconductor layer, which may be generated in scaling up an integrated-type thin film photoelectric conversion device. The thin film photoelectric conversion device includes: a substrate, a transparent electrode layer, a photoelectric conversion unit, and a back electrode layer. An increasing rate ?Zt of the film thickness Zt of the transparent electrode layer along X and an increasing rate ?Zs of the film thickness Zs of the photoelectric conversion unit along X have different signs, whereas one line segment in a parallel direction to a main surface of the substrate is taken as X?.
    Type: Application
    Filed: May 19, 2009
    Publication date: March 17, 2011
    Applicant: KANEKA CORPORATION
    Inventors: Takashi Fujibayashi, Toshiaki Sasaki, Yuko Tawada
  • Patent number: 7851695
    Abstract: The present invention makes it possible to provide a stacked-type thin-film photoelectric conversion device having high photostability, at a high yield rate and significantly reduced production costs. In a stacked-type photoelectric conversion device having an amorphous silicon-based photoelectric conversion unit and a crystalline silicon-based photoelectric conversion unit stacked thereon or vice versa, an amorphous photoelectric conversion layer included in the amorphous photoelectric conversion unit has a thickness of at least 0.03 ?m and less than 0.17 ?m, a crystalline photoelectric conversion layer included in the crystalline photoelectric conversion unit has a thickness of at least 0.2 ?m and less than 1.0 ?m, and a silicon oxide layer of a first conductivity type included in the amorphous photoelectric conversion unit and a silicon layer of a second conductivity type included in the crystalline photoelectric conversion unit make a junction.
    Type: Grant
    Filed: December 19, 2006
    Date of Patent: December 14, 2010
    Assignee: Kaneka Corporation
    Inventors: Toru Sawada, Yuko Tawada, Takashi Suezaki, Kenji Yamamoto
  • Publication number: 20100275996
    Abstract: The invention intends to provide a silicon-based thin-film photoelectric conversion device with conversion efficiency improved at low cost. Specifically, disclosed is a thin-film silicon-based photoelectric conversion device (5) comprising a crystalline photoelectric conversion unit (3), wherein one-conductivity-type semiconductor layer (31), a crystalline silicon-based photoelectric conversion layer (322), and a reverse-conductivity-type semiconductor layer (33) are sequentially stacked. This silicon thin film photoelectric conversion device (5) is also characterized in that a substantially i-type crystalline silicon intervening layer (321), which is made of a material different from that of the photoelectric conversion layer (322), is disposed between the one-conductivity-type semiconductor layer (31) and the photoelectric conversion layer (322), and the photoelectric conversion layer (322) contacts directly with the intervening layer (321).
    Type: Application
    Filed: November 21, 2008
    Publication date: November 4, 2010
    Applicant: KANEKA CORPORATION
    Inventors: Yuko Tawada, Masahiro Goto
  • Patent number: 7781668
    Abstract: An inexpensive substrate for thin film solar cells having improved performance of a thin film solar cell, and a manufacturing method thereof are provided by increasing light trapping effect due to effective increase in unevenness of a substrate for thin film solar cells. Furthermore, a thin film solar cell having improved performance using the substrate is provided. A substrate for thin film solar cells of the present invention has a transparent insulating substrate and a transparent electrode layer deposited thereon including at least zinc oxide (ZnO), the transparent insulating substrate has a fine surface unevenness having a root-mean-square deviation of the surface (RMS) 5 to 50 nm in an interface by a side of the transparent electrode layer, a projected area thereof consists of a curved surface, and furthermore a haze ratio or a ratio of a diffuse transmittance to a total transmittance as an index of unevenness of a substrate may be set at not less than 20% measured using a C light source.
    Type: Grant
    Filed: March 15, 2005
    Date of Patent: August 24, 2010
    Assignee: Kaneka Corporation
    Inventors: Toshiaki Sasaki, Yohei Koi, Yuko Tawada, Kenji Yamamoto
  • Patent number: 7678992
    Abstract: A thin film photoelectric converter, especially an integrated thin film photoelectric converter having improved photoelectric conversion efficiency is provided by controlling an open-circuit voltage and a fill factor so as not be small in a thin film photoelectric converter including a crystalline silicon photoelectric conversion unit. The thin film photoelectric converter by the present invention has at least a transparent electrode film, a crystalline silicon photoelectric conversion unit, and a back electrode film formed sequentially on one principal surface of a transparent substrate, and the converter has a whitish discoloring area on a part of a surface of the converter after formation of the crystalline silicon photoelectric conversion unit. A percentage of dimensions of the whitish discoloring area preferably is not more than 5% of a dimension of the photoelectric conversion area.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: March 16, 2010
    Assignee: Kaneka Corporation
    Inventors: Takashi Suezaki, Masashi Yoshimi, Toshiaki Sasaki, Yuko Tawada, Kenji Yamamoto
  • Publication number: 20100024862
    Abstract: Provided in this invention is a low-cost substrate provided with a transparent conductive film for photoelectric conversion device, which can improve performance of the photoelectric conversion device by enhanced light confinement effect achieved with effectively increased surface unevenness of the substrate. A method for manufacturing said substrate and a photoelectric conversion device using said substrate which can show improved performance are also provided. The substrate provided with the transparent conductive film for the photoelectric conversion device comprises a transparent insulating substrate and a transparent electrode layer containing at least zinc oxide deposited on the transparent insulating substrate, wherein the transparent electrode layer is composed of a double layer structure wherein first and second transparent conductive films are deposited in this order from a substrate side.
    Type: Application
    Filed: November 12, 2007
    Publication date: February 4, 2010
    Applicant: KANEKA CORPORATION
    Inventor: Yuko Tawada
  • Publication number: 20090165853
    Abstract: The present invention makes it possible to provide a stacked-type thin-film photoelectric conversion device having high photostability, at a high yield rate and significantly reduced production costs. In a stacked-type photoelectric conversion device having an amorphous silicon-based photoelectric conversion unit and a crystalline silicon-based photoelectric conversion unit stacked thereon or vice versa, an amorphous photoelectric conversion layer included in the amorphous photoelectric conversion unit has a thickness of at least 0.03 ?m and less than 0.17 ?m, a crystalline photoelectric conversion layer included in the crystalline photoelectric conversion unit has a thickness of at least 0.2 ?m and less than 1.0 ?m, and a silicon oxide layer of a first conductivity type included in the amorphous photoelectric conversion unit and a silicon layer of a second conductivity type included in the crystalline photoelectric conversion unit make a junction.
    Type: Application
    Filed: December 19, 2006
    Publication date: July 2, 2009
    Inventors: Toru Sawada, Yuko Tawada, Takashi Suezaki, Kenji Yamamoto
  • Publication number: 20080185036
    Abstract: An object of the present invention is to provide a substrate for a thin film photoelectric conversion device, in which its properties are not deteriorated when its surface unevenness is effectively increased, and then provide the thin film photoelectric conversion device having its performance improved by using the substrate. According to the present invention, by setting the surface area ratio of a transparent electrode layer in the substrate for the thin film photoelectric conversion device to at least 55% and at most 95%, the surface unevenness are effectively increased to increase the optical confinement effect, while deterioration in properties due to sharpening of the surface level variation is suppressed, whereby making it possible to provide a substrate for a thin film photoelectric conversion device, which can enhance output properties of the thin film photoelectric conversion device.
    Type: Application
    Filed: November 9, 2005
    Publication date: August 7, 2008
    Inventors: Toshiaki Sasaki, Yohei Koi, Yuko Tawada, Takashi Suezaki, Kenji Yamamoto
  • Publication number: 20070169805
    Abstract: An inexpensive substrate for thin film solar cells having improved performance of a thin film solar cell, and a manufacturing method thereof are provided by increasing light trapping effect due to effective increase in unevenness of a substrate for thin film solar cells. Furthermore, a thin film solar cell having improved performance using the substrate is provided. A substrate for thin film solar cells of the present invention has a transparent insulating substrate and a transparent electrode layer deposited thereon including at least zinc oxide (ZnO), the transparent insulating substrate has a fine surface unevenness having a root-mean-square deviation of the surface (RMS) 5 to 50 nm in an interface by a side of the transparent electrode layer, a projected area thereof consists of a curved surface, and furthermore a haze ratio or a ratio of a diffuse transmittance to a total transmittance as an index of unevenness of a substrate may be set at not less than 20% measured using a C light source.
    Type: Application
    Filed: March 15, 2005
    Publication date: July 26, 2007
    Applicant: KANEKA CORPORATION
    Inventors: Toshiaki Sasaki, Yohei Koi, Yuko Tawada, Kenji Yamamoto
  • Publication number: 20060097259
    Abstract: A thin film photoelectric converter, especially an integrated thin film photoelectric converter having improved photoelectric conversion efficiency is provided by controlling an open-circuit voltage and a fill factor so as not be small in a thin film photoelectric converter including a crystalline silicon photoelectric conversion unit. The thin film photoelectric converter by the present invention has at least a transparent electrode film, a crystalline silicon photoelectric conversion unit, and a back electrode film formed sequentially on one principal surface of a transparent substrate, and the converter has a whitish discoloring area on a part of a surface of the converter after formation of the crystalline silicon photoelectric conversion unit. A percentage of dimensions of the whitish discoloring area preferably is not more than 5% of a dimension of the photoelectric conversion area.
    Type: Application
    Filed: May 28, 2004
    Publication date: May 11, 2006
    Inventors: Takashi Suezaki, Masashi Yoshimi, Toshiaki Sasaki, Yuko Tawada, Kenji Yamamoto
  • Publication number: 20050145972
    Abstract: A tandem thin film photoelectric converter includes a transparent electrode, a plurality of photoelectric conversion units and back electrode deposited in sequence on a transparent insulating substrate. An intermediate layer for partially reflecting and transmitting light is inserted along at least one interface between the plurality of photoelectric conversion units. The intermediate layer has an average thickness in the range of 10 to 90 nanometers. The upper surface of the intermediate layer includes an uneven surface geometry having an average peak-to-peak pitch in the range of 10 to 50 nanometers.
    Type: Application
    Filed: January 27, 2003
    Publication date: July 7, 2005
    Inventors: Susumu Fukuda, Yuko Tawada, Youhei Koi, Kenji Yamamoto
  • Patent number: 6759645
    Abstract: A hybrid-type thin film photoelectric converter includes a transparent electrode (12), at least one amorphous photoelectric conversion unit (20), at least one crystalline photoelectric conversion unit (30) and a backside electrode (40), successively stacked on a transparent glass substrate (11). The transparent electrode (12) has a thickness of more than 400 nm and less than 1000 nm. A transparent laminated body (10) including the glass substrate (11) and the transparent electrode (12) has a haze ratio of more than 2% and less than 10%.
    Type: Grant
    Filed: July 19, 2002
    Date of Patent: July 6, 2004
    Assignee: Kaneka Corporation
    Inventors: Yuko Tawada, Kenji Yamamoto
  • Patent number: 6734352
    Abstract: The present invention provides a photoelectric conversion device that improves photoelectric conversion efficiency with the interaction between a transparent substrate with a transparent conductive film, an antireflection film, and a photoelectric conversion unit. The antireflection film contains fine particles having an average particle diameter of 0.01 to 1.0 &mgr;m and has an uneven surface derived from the fine particles. The glass sheet with a transparent conductive film has a light transmittance of 75% or more in the wavelength region of 800 nm to 900 nm. The photoelectric conversion unit includes at least a photoelectric conversion unit including a photoelectric conversion layer having a band gap of 1.85 eV or less.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: May 11, 2004
    Assignees: Nippon Sheet Glass Company, Limited, Kaneka Corporation
    Inventors: Masahiro Hirata, Tsuyoshi Otani, Yuko Tawada
  • Patent number: 6632993
    Abstract: There is provided a photovoltaic module including a transparent substrate and hybrid photovoltaic cells arrayed on the substrate and series connected to each other, the cells including a back electrode facing the substrate, a transparent front electrode intervening between the substrate and the back electrode, a first photovoltaic layer intervening between the front and back electrodes and including an amorphous semiconductor layer, a second photovoltaic layer intervening between the first photovoltaic layer and the back electrode and including a crystalline semiconductor layer, and a conductive interlayer with a light-transmitting-and-reflecting property intervening between the first and second photovoltaic layers and having a thickness in a range of 10 nm to 100 nm and a specific resistance in a range of 1×10−3 &OHgr;·cm to less than 1×10−1 &OHgr;·cm.
    Type: Grant
    Filed: October 2, 2001
    Date of Patent: October 14, 2003
    Assignee: Kaneka Corporation
    Inventors: Katsuhiko Hayashi, Yuko Tawada, Tomomi Meguro, Akihiko Nakajima
  • Publication number: 20030121544
    Abstract: The present invention provides a photoelectric conversion device that improves photoelectric conversion efficiency with the interaction between a transparent substrate with a transparent conductive film, an antireflection film, and a photoelectric conversion unit. The antireflection film contains fine particles having an average particle diameter of 0.01 to 1.0 &mgr;m and has an uneven surface derived from the fine particles. The glass sheet with a transparent conductive film has a light transmittance of 75% or more in the wavelength region of 800 nm to 900 nm. The photoelectric conversion unit includes at least a photoelectric conversion unit including a photoelectric conversion layer having a band gap of 1.85 eV or less.
    Type: Application
    Filed: November 13, 2002
    Publication date: July 3, 2003
    Applicant: NIPPON SHEET GLASS CO., LTD.
    Inventors: Masahiro Hirata, Tsuyoshi Otani, Yuko Tawada
  • Patent number: 6512170
    Abstract: The present invention provides a photoelectric conversion device that improves photoelectric conversion efficiency with the interaction between a transparent substrate with a transparent conductive film, an antireflection film, and a photoelectric conversion unit. The antireflection film contains fine particles having an average particle diameter of 0.01 to 1.0 &mgr;m and has an uneven surface derived from the fine particles. The glass sheet with a transparent conductive film has a light transmittance of 75% or more in the wavelength region of 800 nm to 900 nm. The photoelectric conversion unit includes at least a photoelectric conversion unit including a photoelectric conversion layer having a band gap of 1.85 eV or less.
    Type: Grant
    Filed: October 31, 2001
    Date of Patent: January 28, 2003
    Assignees: Nippon Sheet Glass Co., Ltd., Kaneka Corporation
    Inventors: Masahiro Hirata, Tsuyoshi Otani, Yuko Tawada