Patents by Inventor Naoto Kusumoto

Naoto Kusumoto 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: 20050181583
    Abstract: A semiconductor material and a method for forming the same, said semiconductor material having produced by a process comprising melting a noncrystal semiconductor film containing therein carbon, nitrogen, and oxygen each at a concentration of 5×1019 atoms·cm?3 or lower, preferably 1×1019 atoms·cm?3 or lower, by irradiating a laser beam or a high intensity light equivalent to a laser beam to said noncrystal semiconductor film, and then recrystallizing the thus molten amorphous silicon film. The present invention provides thin film semiconductors having high mobility at an excellent reproducibility, said semiconductor materials being useful for fabricating thin film semiconductor devices such as thin film transistors improved in device characteristics.
    Type: Application
    Filed: April 14, 2005
    Publication date: August 18, 2005
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Hongyong Zhang, Naoto Kusumoto, Yasuhiko Takemura
  • Patent number: 6924212
    Abstract: A preparing method of a semiconductor, particularly a preparing method of a polycrystal semiconductor film which has a good electrical property is disclosed. In order to obtain a non-crystalline silicon film containing a lot of combination of hydrogen and silicon, a forming process of a non-crystalline silicon film by a low temperature gas phase chemical reaction, a process of a heat annealing to produce a lot of dangling bonds of silicon, so as to draw out hydrogen from said non-crystalline silicon film, and a process of applying a laser irradiation to said non-crystal silicon film having a lot of dangling bond of silicon are conducted.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: August 2, 2005
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Honyong Zhang, Naoto Kusumoto
  • Patent number: 6921686
    Abstract: An amorphous semiconductor film is etched so that a width of a narrowest portion thereof is 100 ?m or less, thereby forming island semiconductor regions. By irradiating an intense light such as a laser into the island semiconductor regions, photo-annealing is performed to crystallize it. Then, of end portions (peripheral portions) of the island semiconductor regions, at least a portion used to form a channel of a thin film transistor (TFT), or a portion that a gate electrode crosses is etched, so that a region that the distortion is accumulated is removed. By using such semiconductor regions, a TFT is produced.
    Type: Grant
    Filed: August 28, 2001
    Date of Patent: July 26, 2005
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Naoto Kusumoto, Shunpei Yamazaki
  • Patent number: 6916509
    Abstract: With a conventional cylindrical can method, a region used as a film formation ground electrode is a portion of the cylindrical can, and an apparatus becomes larger in size in proportion to the surface area of the electrode. A conveyor device and a film formation apparatus having the conveyor device are provided, which have a unit for continuously conveying a flexible substrate from one end to the other end, and which are characterized in that a plurality of cylindrical rollers are provided between the one end and the other end along an arc with a radius R, the cylindrical rollers being arranged such that their center axes run parallel to each other, and that a mechanism for conveying the flexible substrate while the substrate is in contact with each of the plurality of cylindrical rollers is provided.
    Type: Grant
    Filed: November 5, 2004
    Date of Patent: July 12, 2005
    Assignees: Semiconductor Energy Laboratory Co., Ltd., TDK Corporation
    Inventors: Masato Yonezawa, Naoto Kusumoto, Hisato Shinohara
  • Publication number: 20050116310
    Abstract: The present invention provides a semiconductor device formed over an insulating substrate, typically a semiconductor device having a structure in which mounting strength to a wiring board can be increased in an optical sensor, a solar battery, or a circuit using a TFT, and which can make it mount on a wiring board with high density, and further a method for manufacturing the same. According to the present invention, in a semiconductor device, a semiconductor element is formed on an insulating substrate, a concave portion is formed on a side face of the semiconductor device, and a conductive film electrically connected to the semiconductor element is formed in the concave portion.
    Type: Application
    Filed: October 5, 2004
    Publication date: June 2, 2005
    Inventors: Kazuo Nishi, Hiroki Adachi, Junya Maruyama, Naoto Kusumoto, Yuusuke Sugawara, Tomoyuki Aoki, Eiji Sugiyama, Hironobu Takahashi
  • Publication number: 20050082655
    Abstract: The present invention provides a semiconductor device having a structure that can be mounted on a wiring substrate, as for the semiconductor device formed over a thin film-thickness substrate, a film-shaped substrate, or a sheet-like substrate. In addition, the present invention provides a method for manufacturing a semiconductor device that is capable of raising a reliability of mounting on a wiring substrate. One feature of the present invention is to bond a semiconductor element formed on a substrate having isolation to a member that a conductive film is formed via a medium having an anisotropic conductivity.
    Type: Application
    Filed: September 29, 2004
    Publication date: April 21, 2005
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Kazuo Nishi, Hiroki Adachi, Naoto Kusumoto, Yuusuke Sugawara, Hidekazu Takahashi, Daiki Yamada, Yoshikazu Hiura
  • Patent number: 6881615
    Abstract: A semiconductor material and a method for forming the same, said semiconductor material having produced by a process comprising melting a noncrystal semiconductor film containing therein carbon, nitrogen, and oxygen each at a concentration of 5×1019 atoms·cm?3 or lower, preferably 1×1019 atoms·cm?3 or lower, by irradiating a laser beam or a high intensity light equivalent to a laser beam to said noncrystal semiconductor film, and then recrystallizing the thus molten amorphous silicon film. The present invention provides thin film semiconductors having high mobility at an excellent reproducibility, said semiconductor materials being useful for fabricating thin film semiconductor devices such as thin film transistors improved in device characteristics.
    Type: Grant
    Filed: October 18, 2001
    Date of Patent: April 19, 2005
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Hongyong Zhang, Naoto Kusumoto, Yasuhiko Takemura
  • Publication number: 20050061246
    Abstract: With a conventional cylindrical can method, a region used as a film formation ground electrode is a portion of the cylindrical can, and an apparatus becomes larger in size in proportion to the surface area of the electrode. A conveyor device and a film formation apparatus having the conveyor device are provided, which have a unit for continuously conveying a flexible substrate from one end to the other end, and which are characterized in that a plurality of cylindrical rollers are provided between the one end and the other end along an arc with a radius R, the cylindrical rollers being arranged such that their center axes run parallel to each other, and that a mechanism for conveying the flexible substrate while the substrate is in contact with each of the plurality of cylindrical rollers is provided.
    Type: Application
    Filed: November 5, 2004
    Publication date: March 24, 2005
    Inventors: Masato Yonezawa, Naoto Kusumoto, Hisato Shinohara
  • Publication number: 20050019997
    Abstract: In order to promote an effect of laser annealing in respect of a semiconductor film, moisture is intentionally included in an atmosphere in irradiating laser beam to the semiconductor film by which a temperature holding layer comprising water vapor is formed on the surface of the semiconductor film in irradiating the laser beam and the laser annealing operation can be performed effectively.
    Type: Application
    Filed: August 20, 2004
    Publication date: January 27, 2005
    Inventors: Naoto Kusumoto, Shunpei Yamazaki, Koichiro Tanaka
  • Publication number: 20050017243
    Abstract: A semiconductor device having a pair of impurity doped second semiconductor layers, formed on a first semiconductor layer having a channel formation region therein, an outer edge of the first semiconductor film being at least partly coextensive with an outer edge of the impurity doped second semiconductor layers. The semiconductor device further includes source and drain electrodes formed on the pair of impurity doped second semiconductor layers, wherein the pair of impurity doped second semiconductor layers extend beyond inner sides edges of the source and drain electrodes so that a stepped portion is formed from an upper surface of the source and drain electrodes to a surface of the first semiconductor film.
    Type: Application
    Filed: August 26, 2004
    Publication date: January 27, 2005
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hongyong Zhang, Naoto Kusumoto
  • Patent number: 6847064
    Abstract: A semiconductor device having a pair of impurity doped second semiconductor layers, formed on a first semiconductor layer having a channel formation region therein, an outer edge of the first semiconductor film being at least partly coextensive with an outer edge of the impurity doped second semiconductor layers. The semiconductor device further includes source and drain electrodes formed on the pair of impurity doped second semiconductor layers, wherein the pair of impurity doped second semiconductor layers extend beyond inner sides edges of the source and drain electrodes so that a stepped portion is formed from an upper surface of the source and drain electrodes to a surface of the first semiconductor film.
    Type: Grant
    Filed: May 8, 2002
    Date of Patent: January 25, 2005
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hongyong Zhang, Naoto Kusumoto
  • Patent number: 6835675
    Abstract: A laser-irradiation method which comprises a process for fabricating a semiconductor device, comprising: a first step of forming a thin film amorphous semiconductor on a substrate having an insulating surface; a second step of modifying the thin film amorphous semiconductor into a crystalline thin film semiconductor by irradiating a pulse-type linear light and/or by applying a heat treatment; a third step of implanting an impurity element which imparts a one conductive type to the crystalline thin film semiconductor; and a fourth step of activating the impurity element by irradiating a pulse-type linear light and/or by applying a heat treatment; wherein the peak value, the peak width at half height, and the threshold width of the laser energy in the second and the fourth steps above are each distributed within a range of approximately ±3% of the standard value. Also claimed is a laser irradiation device which realizes the method above.
    Type: Grant
    Filed: December 10, 2002
    Date of Patent: December 28, 2004
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Satoshi Teramoto, Naoto Kusumoto, Takeshi Fukunaga, Setsuo Nakajima, Tadayoshi Miyamoto, Atsushi Yoshinouchi
  • Patent number: 6827787
    Abstract: With a conventional cylindrical can method, a region used as a film formation ground electrode is a portion of the cylindrical can, and an apparatus becomes larger in size in proportion to the surface area of the electrode. A conveyor device and a film formation apparatus having the conveyor device are provided, which have a unit for continuously conveying a flexible substrate from one end to the other end, and which are characterized in that a plurality of cylindrical rollers are provided between the one end and the other end along an arc with a radius R, the cylindrical rollers being arranged such that their center axes run parallel to each other, and that a mechanism for conveying the flexible substrate while the substrate is in contact with each of the plurality of cylindrical rollers is provided.
    Type: Grant
    Filed: February 5, 2001
    Date of Patent: December 7, 2004
    Assignees: Semiconductor Energy Laboratory Co., Ltd., TDK Corporation
    Inventors: Masato Yonezawa, Naoto Kusumoto, Hisato Shinohara
  • Patent number: 6797548
    Abstract: A method of fabricating silicon TFTs (thin-film transistors) is disclosed. The method comprises a crystallization step by laser irradiation effected after the completion of the device structure. First, amorphous silicon TFTs are fabricated. In each of the TFTs, the channel formation region, the source and drain regions are exposed to laser radiation illuminated from above or below the substrate. Then, the laser radiation is illuminated to crystallize and activate the channel formation region, and source and drain regions. After the completion of the device structure, various electrical characteristics of the TFTs are controlled. Also, the amorphous TFTs can be changed to polysilicon TFTs.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: September 28, 2004
    Assignee: Semiconductor Energy Laboratory Co., Inc.
    Inventors: Hongyong Zhang, Naoto Kusumoto
  • Publication number: 20040152290
    Abstract: In a process for manufacturing a thin film transistor having a semiconductor layer constituting source and drain regions and a channel forming region, by the semiconductor layer being made thinner in the source and drain regions than in the channel forming region a structure is realized wherein, at the boundary between the source region and the channel forming region and the boundary between the drain region and the channel forming region, portions where electric field concentrations occur are displaced from the portion where a channel is formed. By reducing the OFF current (the leak current) without also reducing the ON current, a high mutual conductance is realized.
    Type: Application
    Filed: January 21, 2004
    Publication date: August 5, 2004
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Naoto Kusumoto
  • Patent number: 6770143
    Abstract: A method for manufacturing a semiconductor device including preparing a multi-chamber system having at least first and second chambers, the first chamber for forming a film and the second chamber for processing an object with a laser light; processing a substrate in one of the first and second chambers; transferring the substrate to the other one of the first and second chambers; and processing the substrate in the other one of the chambers, wherein the first and second chambers can be isolated from one another by using a gate valve.
    Type: Grant
    Filed: August 22, 2002
    Date of Patent: August 3, 2004
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hongyong Zhang, Naoto Kusumoto
  • Patent number: 6756258
    Abstract: A method of fabricating silicon TFTs (thin-film transistors) is disclosed. The method comprises a crystallization step by laser irradiation effected after the completion of the device structure. First, amorphous silicon TFTs are fabricated. In each of the TFTs, the channel formation region, the source and drain regions are exposed to laser radiation illuminated from above or below the substrate. Then, the laser radiation is illuminated to crystallize and activate the channel formation region, and source and drain regions. After the completion of the device structure, various electrical characteristics of the TFTs are controlled. Also, the amorphous TFTs can be changed into polysilicon TFTs.
    Type: Grant
    Filed: May 8, 2002
    Date of Patent: June 29, 2004
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hongyong Zhang, Naoto Kusumoto
  • Publication number: 20040087069
    Abstract: In crystallizing an amorphous silicon film by illuminating it with linear pulse laser beams having a normal-distribution type beam profile or a similar beam profile, the linear pulse laser beams are applied in an overlapped manner. There can be obtained effects similar to those as obtained by a method in which the laser illumination power is gradually increased and then decreased in a step-like manner in plural scans.
    Type: Application
    Filed: June 25, 2003
    Publication date: May 6, 2004
    Applicant: Semiconductor Energy Laboratory Co., Ltd. a Japan Corporation
    Inventors: Naoto Kusumoto, Koichiro Tanaka
  • Patent number: 6709905
    Abstract: An amorphous semiconductor film is etched so that a width of a narrowest portion thereof is 100 &mgr;m or less, thereby forming island semiconductor regions. By irradiating an intense light such as a laser into the island semiconductor regions, photo-annealing is performed to crystallize it. Then, of end portions (peripheral portions) of the island semiconductor regions, at least a portion used to form a channel of a thin film transistor (TFT), or a portion that a gate electrode crosses is etched, so that a region that the distortion is accumulated is removed. By using such semiconductor regions, a TFT is produced.
    Type: Grant
    Filed: August 28, 2001
    Date of Patent: March 23, 2004
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Naoto Kusumoto, Shunpei Yamazaki
  • Patent number: 6683350
    Abstract: In a process for manufacturing a thin film transistor having a semiconductor layer constituting source and drain regions and a channel forming region, by the semiconductor layer being made thinner in the source and drain regions than in the channel forming region a structure is realized wherein, at the boundary between the source region and the channel forming region and the boundary between the drain region and the channel forming region, portions where electric field concentrations occur are displaced from the portion where a channel is formed. By reducing the OFF current (the leak current) without also reducing the ON current, a high mutual conductance is realized.
    Type: Grant
    Filed: March 6, 2000
    Date of Patent: January 27, 2004
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Naoto Kusumoto