Patents by Inventor Takafumi Mizoguchi

Takafumi Mizoguchi 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: 20120132918
    Abstract: A display device free of contact resistance between a drain electrode (or a source electrode) and a pixel electrode. The display device includes a gate electrode, a gate insulating layer covering the gate electrode, a semiconductor layer formed over the gate insulating layer, and a source electrode and a drain electrode separated from each other and in partial-contact with and over the semiconductor layer, and one of the source electrode and the drain electrode also serves as a pixel electrode, the other of the source electrode and the drain electrode also serves as a signal line, and a low resistant conductive layer is preferably formed over the other of the source electrode and the drain electrode. The low resistant conductive layer can be formed by an electroplating method or the like.
    Type: Application
    Filed: November 29, 2011
    Publication date: May 31, 2012
    Inventor: Takafumi Mizoguchi
  • Patent number: 8168461
    Abstract: The present invention improves mechanical strength of a micro-electro-mechanical device (MEMS) having a movable portion to improve reliability. In a micro-electro-mechanical device (MEMS) having a movable portion, a portion which has been a hollow portion in the case of a conventional structure is filled with a filler material. As the filler material, a block copolymer that is highly flexible is used, for example. By filling the hollow portion, mechanical strength improves. Besides, warpage of an upper portion of a structure body in the manufacture process is prevented, whereby yield improves. A micro-electro-mechanical device thus manufactured is highly reliable.
    Type: Grant
    Filed: December 8, 2010
    Date of Patent: May 1, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Kaoru Tsuchiya, Takafumi Mizoguchi
  • Publication number: 20120094433
    Abstract: Provided is a method for manufacturing a semiconductor device so as not expose a semiconductor layer to moisture and the number of masks is reduced. For example, a first conductive film, a first insulating film, a semiconductor film, a second conductive film, and a mask film are formed. The first mask film is processed to form a first mask layer. Dry etching is performed on the first insulating film, the semiconductor film, and the second conductive film with the use of the first mask layer to form a thin film stack body, so that a surface of the first conductive film is at least exposed. Sidewall insulating layers covering side surfaces of the thin film stack body are formed. The first conductive film is side-etched to form a first electrode. A second electrode layer is formed with the second mask layer.
    Type: Application
    Filed: September 24, 2011
    Publication date: April 19, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takafumi MIZOGUCHI, Kojiro SHIRAISHI
  • Publication number: 20120086000
    Abstract: An object is to provide a method for manufacturing a semiconductor device without exposing a specific layer to moisture or the like at all. A thin film element is manufactured in such a manner that a first film, a second film, and a third film are stacked in this order; a resist mask is formed over the third film; a mask layer is formed by etching the third film with the use of the resist mask; the resist mask is removed; a second layer and a first layer are formed by performing dry etching on the second film and the first film with the use of the mask layer; a fourth film is formed to cover at least the second layer and the first layer; and sidewall layers are formed to cover at least the entire side surfaces of the first layer by performing etch back on the fourth film.
    Type: Application
    Filed: September 20, 2011
    Publication date: April 12, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takafumi MIZOGUCHI, Kojiro SHIRAISHI, Masashi TSUBUKU
  • Publication number: 20120081646
    Abstract: To provide a liquid crystal display device excellent in mechanical reliability, in which gap holding materials are arranged uniformly in a limited pixel, in an active matrix liquid crystal display device including a columnar gap holding material and liquid crystal between two substrates which face each other, at least one of wirings in a thin film transistor includes a non-expanded portion which is connected to any of electrodes of the thin film transistor and a expanded portion having a first region having the same wiring width as the non-expanded portion and a second region in contact with the first region. Further, one side of the columnar gap holding material is in contact with components on the second substrate, and the other side of the columnar gap holding material is in contact with components provided over the first substrate. Furthermore, the columnar gap holding material overlaps with the expanded portion.
    Type: Application
    Filed: September 23, 2011
    Publication date: April 5, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takafumi MIZOGUCHI, Takayuki Kato
  • Publication number: 20120056182
    Abstract: A manufacturing method of a semiconductor device having a stacked structure in which a lower layer is exposed is provided without increasing the number of masks. A source electrode layer and a drain electrode layer are formed by forming a conductive film to have a two-layer structure, forming an etching mask thereover, etching the conductive film using the etching mask, and performing side-etching on an upper layer of the conductive film in a state where the etching mask is left so that part of a lower layer is exposed. The thus formed source and drain electrode layers and a pixel electrode layer are connected in a portion of the exposed lower layer. In the conductive film, the lower layer and the upper layer may be a Ti layer and an Al layer, respectively. The plurality of openings may be provided in the etching mask.
    Type: Application
    Filed: September 1, 2011
    Publication date: March 8, 2012
    Inventors: Hidekazu Miyairi, Takafumi Mizoguchi
  • Publication number: 20120049283
    Abstract: A dual-gate transistor including: a first insulating layer provided to cover a first conductive layer; a first semiconductor layer over the first insulating layer; second semiconductor layers over the first semiconductor layer, the second semiconductor layers are spaced from each other to expose the first semiconductor layer; impurity semiconductor layers over the second semiconductor layers; second conductive layers over the impurity semiconductor layers; second insulating layers over the second conductive layers; a third insulating layer to cover the first semiconductor layer, the second semiconductor layers, the impurity semiconductor layers, the second conductive layers, and the second insulating layers; and a third conductive layer at least over the third insulating layer, and in the dual-gate transistor including the first to third insulating layers with openings, the first insulating layer is substantially equal in thickness to the second insulating layer.
    Type: Application
    Filed: August 22, 2011
    Publication date: March 1, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Hidekazu MIYAIRI, Takafumi MIZOGUCHI
  • Publication number: 20120007087
    Abstract: A first conductive film, a first insulating film, a semiconductor film, an impurity semiconductor film, a second conductive film, and a first resist mask are formed; first etching is performed to expose at least a surface of the first conductive film; second etching accompanied by side etching is performed on part of the first conductive film to form a gate electrode layer; a second resist mask is formed; third etching is performed to form a source and drain electrode layers, a source and drain regions, and a semiconductor layer; a second insulating film is formed; an opening portion is formed in the second insulating film to partially expose the source or drain electrode layer; a pixel electrode is selectively formed in the opening portion and over the second insulating film; and a supporting portion formed using the gate electrode layer is formed in a region overlapping with the opening portion.
    Type: Application
    Filed: September 21, 2011
    Publication date: January 12, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takafumi MIZOGUCHI, Mayumi MIKAMI, Yumiko SAITO
  • Publication number: 20110315990
    Abstract: To provide a semiconductor device in which a channel formation region can be thinned without adversely affecting a source region and a drain region through a simple process and a method for manufacturing the semiconductor device. In the method for manufacturing a semiconductor device, a semiconductor film, having a thickness smaller than a height of a projection of a substrate, is formed over a surface of the substrate having the projections; the semiconductor film is etched to have an island shape with a resist used as a mask; the resist is etched to expose a portion of the semiconductor film which covers a top surface of the projection; and the exposed portion of the semiconductor film is etched to be thin, while the adjacent portions of the semiconductor film on both sides of the projection remain covered with the resist.
    Type: Application
    Filed: September 6, 2011
    Publication date: December 29, 2011
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Masaharu NAGAI, Takafumi MIZOGUCHI
  • Publication number: 20110263060
    Abstract: An object is to provide a method for manufacturing a thin film transistor and a display device with reduced number of masks, in which adverse effects of optical current are suppressed. A manufacturing method comprises forming a stack including, from bottom to top, a light-blocking film, a base film, a first conductive film, a first insulating film, a semiconductor film, an impurity semiconductor film, and a second conductive film; performing first etching on the whole thickness of the stack using a first resist mask formed over it; forming a gate electrode layer by side etching the first conductive film in a second etching; forming a second resist mask over the stack; and performing third etching down to the semiconductor film, and partially etching it, using the second resist mask to form a source and drain electrode layer, a source and drain region, and a semiconductor layer.
    Type: Application
    Filed: July 5, 2011
    Publication date: October 27, 2011
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Hidekazu Miyairi, Takafumi MIZOGUCHI
  • Patent number: 8034674
    Abstract: To provide a semiconductor device in which a channel formation region can be thinned without adversely affecting a source region and a drain region through a simple process and a method for manufacturing the semiconductor device. In the method for manufacturing a semiconductor device, a semiconductor film, having a thickness smaller than a height of a projection of a substrate, is formed over a surface of the substrate having the projections; the semiconductor film is etched to have an island shape with a resist used as a mask; the resist is etched to expose a portion of the semiconductor film which covers a top surface of the projection; and the exposed portion of the semiconductor film is etched to be thin, while the adjacent portions of the semiconductor film on both sides of the projection remain covered with the resist.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: October 11, 2011
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Masaharu Nagai, Takafumi Mizoguchi
  • Patent number: 8035107
    Abstract: A first conductive film, a first insulating film, a semiconductor film, an impurity semiconductor film, a second conductive film, and a first resist mask are formed; first etching is performed to expose at least a surface of the first conductive film; second etching accompanied by side etching is performed on part of the first conductive film to form a gate electrode layer; a second resist mask is formed; third etching is performed to form a source and drain electrode layers, a source and drain regions, and a semiconductor layer; a second insulating film is formed; an opening portion is formed in the second insulating film to partially expose the source or drain electrode layer; a pixel electrode is selectively formed in the opening portion and over the second insulating film; and a supporting portion formed using the gate electrode layer is formed in a region overlapping with the opening portion.
    Type: Grant
    Filed: February 10, 2009
    Date of Patent: October 11, 2011
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Takafumi Mizoguchi, Mayumi Mikami, Yumiko Saito
  • Patent number: 7989275
    Abstract: A light-blocking layer is formed using a first resist mask, and a base film is formed over the light-blocking layer. A first conductive film, a first insulating film, a semiconductor film, an impurity semiconductor film, and a second conductive film are sequentially formed over the base film, and first etching is performed on the second conductive film, the impurity semiconductor film, the semiconductor film, and the first insulating film using a second resist mask over the second conductive film. Then, second etching in which side-etching is performed is performed on part of the first conductive film to form a gate electrode layer, and source and drain electrode layers, source and drain region layers, and a semiconductor layer are formed using a third resist mask. The first resist mask and the second resist mask are formed using the same photomask. Thus, a thin film transistor is manufactured.
    Type: Grant
    Filed: March 3, 2009
    Date of Patent: August 2, 2011
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Takafumi Mizoguchi
  • Patent number: 7989234
    Abstract: An object is to provide a method for manufacturing a thin film transistor and a display device with reduced number of masks, in which adverse effects of optical current are suppressed. A manufacturing method comprises forming a stack including, from bottom to top, a light-blocking film, a base film, a first conductive film, a first insulating film, a semiconductor film, an impurity semiconductor film, and a second conductive film; performing first etching on the whole thickness of the stack using a first resist mask formed over it; forming a gate electrode layer by side etching the first conductive film in a second etching; forming a second resist mask over the stack; and performing third etching down to the semiconductor film, and partially etching it, using the second resist mask to form a source and drain electrode layer, a source and drain region, and a semiconductor layer.
    Type: Grant
    Filed: January 28, 2010
    Date of Patent: August 2, 2011
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Takafumi Mizoguchi
  • Publication number: 20110159626
    Abstract: The present invention improves mechanical strength of a micro-electro-mechanical device (MEMS) having a movable portion to improve reliability. In a micro-electro-mechanical device (MEMS) having a movable portion, a portion which has been a hollow portion in the case of a conventional structure is filled with a filler material. As the filler material, a block copolymer that is highly flexible is used, for example. By filling the hollow portion, mechanical strength improves. Besides, warpage of an upper portion of a structure body in the manufacture process is prevented, whereby yield improves. A micro-electro-mechanical device thus manufactured is highly reliable.
    Type: Application
    Filed: December 8, 2010
    Publication date: June 30, 2011
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Kaoru Tsuchiya, Takafumi MIZOGUCHI
  • Publication number: 20110156042
    Abstract: A thin film transistor is provided with a high crystallized region in a channel formation region and a high resistance region between a source and a drain, and thus has a high electric effect mobility and a large on current. The thin film transistor includes an “impurity which suppresses generation of crystal nuclei” contained in the base layer or located on its surface, a first wiring layer over a base layer, an impurity semiconductor layer over the first wiring, a semiconductor layer over the impurity semiconductor layer, the semiconductor layer comprises a crystalline region and a region containing an amorphous phase which is formed adjacent to the base layer.
    Type: Application
    Filed: December 23, 2010
    Publication date: June 30, 2011
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Hidekazu MIYAIRI, Ryu KOMATSU, Takafumi MIZOGUCHI
  • Publication number: 20110076561
    Abstract: The characteristics of a power storage device are improved and the lifetime of the power storage device is prolonged. An electrode is manufactured through the following steps: a step of forming an electrode film; a step of forming a damage layer by ion doping on the electrode film; and a step of providing a damage region between the damage layer and a surface. Alkali ion insertion and extraction can be performed by dipping of an electrode, in which the damage layer and the damage region are formed, in a solution containing an alkali ion. A space in which the volume of the electrode is expanded can be secured by the formation of the damage layer and the damage region. Note that another lithium may be used instead of an alkali metal.
    Type: Application
    Filed: September 27, 2010
    Publication date: March 31, 2011
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Kazutaka Kuriki, Junpei Momo, Takafumi Mizoguchi
  • Publication number: 20110032223
    Abstract: It is an object to provide a display panel and an electronic book which are manufactured with high yield and have high reliability. A display panel is provided which includes, a flexible display portion in which a scan line and a signal line intersect with each other over a substrate, a signal line driver circuit for outputting a first signal to the signal line adjacent to a first side of the flexible display portion over the substrate, and a scan line driver circuit for outputting a second signal to the scan line adjacent to a second side of the flexible display portion. In the display panel, the mechanical strength of a portion provided with the signal line driver circuit or the scan line driver circuit is improved as compared to the mechanical strength of other than the portion.
    Type: Application
    Filed: August 4, 2010
    Publication date: February 10, 2011
    Inventors: Satohiro Okamoto, Takafumi Mizoguchi
  • Patent number: 7883943
    Abstract: A method for manufacturing a thin film transistor and a display device using a small number of masks is provided. A conductive film is formed, a thin-film stack body having a pattern is formed over the conductive film, an opening portion is formed in the thin-film stack body so as to reach the conductive film, a gate electrode layer is formed by processing the conductive film using side-etching, and an insulating layer, a semiconductor layer, and a source and drain electrode layer are formed over the gate electrode layer, whereby a thin film transistor is manufactured. By provision of the opening portion, controllability of etching is improved.
    Type: Grant
    Filed: March 4, 2009
    Date of Patent: February 8, 2011
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Takafumi Mizoguchi
  • Patent number: 7872320
    Abstract: The present invention improves mechanical strength of a micro-electro-mechanical device (MEMS) having a movable portion to improve reliability. In a micro-electro-mechanical device (MEMS) having a movable portion, a portion which has been a hollow portion in the case of a conventional structure is filled with a filler material. As the filler material, a block copolymer that is highly flexible is used, for example. By filling the hollow portion, mechanical strength improves. Besides, warpage of an upper portion of a structure body in the manufacture process is prevented, whereby yield improves. A micro-electro-mechanical device thus manufactured is highly reliable.
    Type: Grant
    Filed: November 5, 2008
    Date of Patent: January 18, 2011
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Kaoru Tsuchiya, Takafumi Mizoguchi