Patents by Inventor Aiko Shiga

Aiko Shiga 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: 20040157413
    Abstract: By adding a novel improvement to the technique disclosed in JP 8-78329 A, a manufacturing method in which film characteristics of a semiconductor film having a crystalline structure are improved is provided. In addition, a TFT having superior TFT characteristics, such as field effect mobility, which uses the semiconductor film as an active layer, and a method of manufacturing the TFT, are also provided. A metallic element which promotes the crystallization of silicon is added to a semiconductor film having an amorphous structure and an oxygen concentration within the film of less than 5×1018/cm3. The semiconductor film having an amorphous structure is then heat-treated, forming a semiconductor film having a crystalline structure. Subsequently, an oxide film on the surface is removed. Oxygen is introduced to the semiconductor film having a crystalline structure, and processing is performed such that the concentration of oxygen within the film is from 5×1018/cm3 to 1×1021/cm3.
    Type: Application
    Filed: February 5, 2004
    Publication date: August 12, 2004
    Applicants: Semiconductor Energy Laboratory Co., Ltd., Sharp Kabushiki Kaisha
    Inventors: Hidekazu Miyairi, Aiko Shiga, Katsumi Nomura, Naoki Makita, Takuya Matsuo
  • Patent number: 6767799
    Abstract: A laser beam irradiation method that achieves uniform crystallization, even if a film thickness of an a-Si film or the like fluctuates, is provided. The present invention provides a laser beam irradiation method in which a non-single crystal semiconductor film is formed on a substrate having an insulating surface and a laser beam having a wavelength longer than 350 nm is irradiated to the non-single crystal semiconductor film, thus crystallizing the non-single crystal silicon film. The non-single crystal semiconductor film has a film thickness distribution within the surface of the substrate, and a differential coefficient of a laser beam absorptivity with respect to the film thickness of the non-single crystal semiconductor film is positive.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: July 27, 2004
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akihisa Shimomura, Kenji Kasahara, Aiko Shiga, Hidekazu Miyairi, Koichiro Tanaka, Koji Dairiki
  • Patent number: 6764886
    Abstract: Island-like semiconductor films and markers are formed prior to laser irradiation. Markers are used as positional references so as not to perform laser irradiation all over the semiconductor within a substrate surface, but to perform a minimum crystallization on at least indispensable portion. Since the time required for laser crystallization can be reduced, it is possible to increase the substrate processing speed. By applying the above-described constitution to a conventional SLS method, a means for solving such problem in the conventional SLS method that the substrate processing efficiency is insufficient, is provided.
    Type: Grant
    Filed: December 10, 2002
    Date of Patent: July 20, 2004
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Akihisa Shimomura, Hisashi Ohtani, Masaaki Hiroki, Koichiro Tanaka, Aiko Shiga, Mai Akiba, Kenji Kasahara
  • Publication number: 20040132266
    Abstract: Provided are a laser apparatus of continuous oscillation that is capable of enhancing the efficiency of substrate processing, a laser irradiation method, and a manufacturing method for a semiconductor device using the laser apparatus. A portion of a semiconductor film that should be left on a substrate after patterning is grasped in accordance with a mask. Then, a portion to be scanned with a laser light is determined so that it is possible to crystallize at least the portion to be obtained through the patterning. Also, a beam spot is made to strike the portion to be scanned. As a result, the semiconductor film is partially crystallized. That is, with the present invention, the laser light is not scanned and irradiated onto the entire surface of a semiconductor film but is scanned so that at least an indispensable portion is crystallized.
    Type: Application
    Filed: December 19, 2003
    Publication date: July 8, 2004
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Hisashi Ohtani, Masaaki Hiroki, Koichiro Tanaka, Aiko Shiga, Mai Akiba
  • Publication number: 20040072411
    Abstract: A method for manufacturing a semiconductor device having steps of forming an amorphous semiconductor on a substrate having an insulating surface; patterning the amorphous semiconductor to form plural first island-like semiconductors; irradiating a linearly condensed laser beam on the plural first island-like semiconductors while relatively scanning the substrate, thus crystallizing the plural first island-like semiconductors; patterning the plural first island-like semiconductors that have been crystallized into to form plural second island-like semiconductors; forming plural transistors using the plural second island-like semiconductors; and forming a unit circuit using a predetermined number of the transistors, where the second island-like semiconductors used for the predetermined number of the transistors are formed from the first island-like semiconductors that are different from each other.
    Type: Application
    Filed: December 27, 2002
    Publication date: April 15, 2004
    Inventors: Munehiro Azami, Chiho Kokubo, Aiko Shiga, Atsuo Isobe, Hiroshi Shibata, Shunpei Yamazaki
  • Patent number: 6700096
    Abstract: Provided are a laser apparatus of continuous oscillation that is capable of enhancing the efficiency of substrate processing, a laser irradiation method, and a manufacturing method for a semiconductor device using the laser apparatus. A portion of a semiconductor film that should be left on a substrate after patterning is grasped in accordance with a mask. Then, a portion to be scanned with a laser light is determined so that it is possible to crystallize at least the portion to be obtained through the patterning. Also, a beam spot is made to strike the portion to be scanned. As a result, the semiconductor film is partially crystallized. That is, with the present invention, the laser light is not scanned and irradiated onto the entire surface of a semiconductor film but is scanned so that at least an indispensable portion is crystallized.
    Type: Grant
    Filed: October 25, 2002
    Date of Patent: March 2, 2004
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Hisashi Ohtani, Masaaki Hiroki, Koichiro Tanaka, Aiko Shiga, Mai Akiba
  • Publication number: 20030234395
    Abstract: In a conventional method of crystallization using a laser beam, variance (or dispersion) in a TFT characteristic becomes large, which causes various functions of a semiconductor device comprising TFTs as components of its electronic circuit to be restrained.
    Type: Application
    Filed: December 18, 2002
    Publication date: December 25, 2003
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD
    Inventors: Chiho Kokubo, Aiko Shiga, Shunpei Yamazaki, Hidekazu Miyairi, Koji Dairiki, Koichiro Tanaka
  • Publication number: 20030235971
    Abstract: Position control of a crystal grain in accordance with an arrangement of a TFT is achieved, and at the same time, a processing speed during a crystallization process is increased. More specifically, there is provided a manufacturing method for a semiconductor device, in which crystal having a large grain size can be continuously formed through super lateral growth that is artificially controlled and substrate processing efficiency during a laser crystallization process can be increased. In the manufacturing method for a semiconductor device, instead of performing laser irradiation on an entire semiconductor film within a substrate surface, a marker as a reference for positioning is formed so as to crystallize at least an indispensable portion at minimum. Thus, a time period required for laser crystallization can be reduced to make it possible to increase a processing speed for a substrate.
    Type: Application
    Filed: November 29, 2002
    Publication date: December 25, 2003
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Akihisa Shimomura, Hisashi Ohtani, Masaaki Hiroki, Koichiro Tanaka, Aiko Shiga, Mai Akiba, Kenji Kasahara
  • Publication number: 20030224550
    Abstract: To provide a method of efficiently configuring a circuit requiring high inter-device consistency by using thin-film transistors. A semiconductor layer is formed on a substrate and is patterned into desired shapes to form first semiconductor islands. The first semiconductor islands are uniformly crystallized by laser irradiation within the surface areas thereof. Thereafter, the semiconductor layers are patterned into desired shapes to become active layers of the thin-film transistors layer. Active layers of all of thin-film transistors constituting one unitary circuit are formed of one of the first semiconductor islands in this case. Thus, the TFTs mutually realize high consistency.
    Type: Application
    Filed: December 18, 2002
    Publication date: December 4, 2003
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Chiho Kokubo, Aiko Shiga, Yoshifumi Tanada, Shunpei Yamazaki
  • Publication number: 20030215973
    Abstract: Island-like semiconductor films and markers are formed prior to laser irradiation. Markers are used as positional references so as not to perform laser irradiation all over the semiconductor within a substrate surface, but to perform a minimum crystallization on at least indispensable portion. Since the time required for laser crystallization can be reduced, it is possible to increase the substrate processing speed. By applying the above-described constitution to a conventional SLS method, a means for solving such problem in the conventional SLS method that the substrate processing efficiency is insufficient, is provided.
    Type: Application
    Filed: December 10, 2002
    Publication date: November 20, 2003
    Applicant: Semiconductor Energy
    Inventors: Shunpei Yamazaki, Akihisa Shimomura, Hisashi Ohtani, Masaaki Hiroki, Koichiro Tanaka, Aiko Shiga, Mai Akiba, Kenji Kasahara
  • Publication number: 20030211714
    Abstract: A laser irradiation method using a laser crystallization method which can heighten an efficiency of substrate processing as compared to a conventional one and also heighten mobility of a semiconductor film is provided. It is an irradiation method of a laser beam in which, pattern information of a sub-island formed on a substrate is stored, and a beam spot of a laser beam is condensed so as to become linear, and by use of the stored pattern information, a scanning path of the beam spot is determined so as to include the sub-island, and by moving the beam spot along the scanning path, the laser beam is irradiated to the sub-island, characterized in that on the occasion of scanning the beam spot, when the beam spot has reached to the sub-island, the beam spot and the sub-island are contacted at a plurality of points.
    Type: Application
    Filed: December 13, 2002
    Publication date: November 13, 2003
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Shunpei Yamazaki, Chiho Kokubo, Aiko Shiga, Koichiro Tanaka, Hidekazu Miyairi, Koji Dairiki
  • Publication number: 20030178682
    Abstract: An object is to form a crystalline semiconductor film having good crystallinity by applying a CW laser thereto, and to achieve a TFT capable of very high speed operation by using the semiconductor film thus obtained. A p-type impurity element is added to crystalline silicon (semiconductor layer), which has a film thickness of 60 to 400 nm and is formed by using a CW laser, in particular, to a channel formation region in a region that becomes an n-channel TFT. The p-type impurity element is added at an acceleration energy of 30 to 120 keV so that its concentration becomes 1×1015 to 5×1018 /cm3.
    Type: Application
    Filed: December 20, 2002
    Publication date: September 25, 2003
    Inventors: Takeshi Noda, Tatsuya Arao, Aiko Shiga, Hidekazu Miyairi, Masayuki Kajiwara
  • Publication number: 20030180992
    Abstract: A laser beam irradiation method that achieves uniform crystallization, even if a film thickness of an a-Si film or the like fluctuates, is provided. The present invention provides a laser beam irradiation method in which a non-single crystal semiconductor film is formed on a substrate having an insulating surface and a laser beam having a wavelength longer than 350 nm is irradiated to the non-single crystal semiconductor film, thus crystallizing the non-single crystal silicon film. The non-single crystal semiconductor film has a film thickness distribution within the surface of the substrate, and a differential coefficient of a laser beam absorptivity with respect to the film thickness of the non-single crystal semiconductor film is positive.
    Type: Application
    Filed: December 20, 2002
    Publication date: September 25, 2003
    Inventors: Akihisa Shimomura, Kenji Kasahara, Aiko Shiga, Hidekazu Miyairi, Koichiro Tanaka, Koji Dairiki
  • Publication number: 20030171837
    Abstract: Providing a semiconductor fabricating apparatus using a laser crystallization technique for enhancing the processing efficiency for substrate and for increasing the mobility of a semiconductor film. The semiconductor fabricating apparatus of multi-chamber system includes a film formation equipment for forming a semiconductor film, and a laser irradiation equipment. The laser irradiation equipment includes first means for controlling a laser irradiation position relative to an irradiation object, second means (laser oscillator) for emitting laser light, third means (optical system) for processing or converging the laser light, and fourth means for controlling the oscillation of the second means and for controlling the first means in a manner that a beam spot of the laser light processed by the third means may cover a place determined based on data on a mask configuration (pattern information).
    Type: Application
    Filed: November 21, 2002
    Publication date: September 11, 2003
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Shunpei Yamazaki, Hisashi Ohtani, Masaaki Hiroki, Koichiro Tanaka, Aiko Shiga, Mai Akiba
  • Publication number: 20030153182
    Abstract: Each region, which should be left on a substrate after patterning, of a semiconductor film is grasped in accordance with a mask. Then, each region to be scanned with laser light is determined so that at least the region to be obtained through the patterning is crystallized, and a beam spot is made to hit the region to be scanned, thereby partially crystallizing the semiconductor film. Each portion with low output energy of the beam spot is shielded by a slit. In the present invention, the laser light is not scanned and irradiated onto the entire surface of the semiconductor film but is scanned such that at least each indispensable portion is crystallized to a minimum. With the construction described above, it becomes possible to save time taken to irradiate the laser light onto each portion to be removed through the patterning after the crystallization of the semiconductor film.
    Type: Application
    Filed: November 27, 2002
    Publication date: August 14, 2003
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Shunpei Yamazaki, Hisashi Ohtani, Masaaki Hiroki, Koichiro Tanaka, Aiko Shiga, Satoshi Murakami, Mai Akiba
  • Publication number: 20030148594
    Abstract: To provide a continuous-oscillating laser apparatus capable of improving the efficiency of substrate treatment, a method of irradiating a laser beam, and a method of manufacturing a semiconductor device using the laser apparatus. Of the entire semiconductor film, a portion that needs to be left on the substrate after patterning is identified according to a mask. Then, a portion to be scanned by respective lasers are defined, so that a laser beam is irradiated twice in different scanning directions to a portion to be obtained at least through patterning and beam spots are impinged upon the scanned portion, thereby partially crystallizing the semiconductor film. In other words, in the invention, it is arranged in such a manner that a laser beam is not irradiated by scanning a laser beam across the entire semiconductor film but by scanning a laser beam twice at least to the absolutely necessary portion.
    Type: Application
    Filed: November 7, 2002
    Publication date: August 7, 2003
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Shunpei Yamazaki, Hisashi Ohtani, Masaaki Hiroki, Koichiro Tanaka, Aiko Shiga, Akihisa Shimomura, Mai Akiba
  • Publication number: 20030136772
    Abstract: Provided are a laser apparatus of continuous oscillation that is capable of enhancing the efficiency of substrate processing, a laser irradiation method, and a manufacturing method for a semiconductor device using the laser apparatus. A portion of a semiconductor film that should be left on a substrate after patterning is grasped in accordance with a mask. Then, a portion to be scanned with a laser light is determined so that it is possible to crystallize at least the portion to be obtained through the patterning. Also, a beam spot is made to strike the portion to be scanned. As a result, the semiconductor film is partially crystallized. That is, with the present invention, the laser light is not scanned and irradiated onto the entire surface of a semiconductor film but is scanned so that at least an indispensable portion is crystallized.
    Type: Application
    Filed: October 25, 2002
    Publication date: July 24, 2003
    Inventors: Shunpei Yamazaki, Hisashi Ohtani, Masaaki Hiroki, Koichiro Tanaka, Aiko Shiga, Mai Akiba
  • Publication number: 20030089909
    Abstract: By adding a novel improvement to the technique disclosed in JP 8-78329 A, a manufacturing method in which film characteristics of a semiconductor film having a crystalline structure are improved is provided. In addition, a TFT having superior TFT characteristics, such as field effect mobility, which uses the semiconductor film as an active layer, and a method of manufacturing the TFT, are also provided. A metallic element which promotes the crystallization of silicon is added to a semiconductor film having an amorphous structure and an oxygen concentration within the film of less than 5×1018/cm3. The semiconductor film having an amorphous structure is then heat-treated, forming a semiconductor film having a crystalline structure. Subsequently, an oxide film on the surface is removed. Oxygen is introduced to the semiconductor film having a crystalline structure, and processing is performed such that the concentration of oxygen within the film is from 5×1018/cm3 to 1×1021/cm3.
    Type: Application
    Filed: October 8, 2002
    Publication date: May 15, 2003
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Aiko Shiga, Katsumi Nomura, Naoki Makita, Takuya Matsuo
  • Publication number: 20030089690
    Abstract: Continuous wave laser apparatus with enhanced processing efficiency is provided as well as a method of manufacturing a semiconductor device using the laser apparatus. The laser apparatus has: a laser oscillator; a unit for rotating a process object; a unit for moving the center of the rotation along a straight line; and an optical system for processing laser light that is outputted from the laser oscillator to irradiate with the laser light a certain region within the moving range of the process object. The laser apparatus is characterized in that the certain region is on a line extended from the straight line and that the position at which the certain region overlaps the process object is moved by rotating the process object while moving the center of the rotation along the straight line.
    Type: Application
    Filed: September 9, 2002
    Publication date: May 15, 2003
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Koichiro Tanaka, Hidekazu Miyairi, Aiko Shiga, Akihisa Shimomura, Mai Akiba
  • Publication number: 20030086182
    Abstract: The present invention is characterized in that by laser beam being slantly incident to the convex lens, an aberration such as astigmatism or the like is occurred, and the shape of the laser beam is made linear on the irradiation surface or in its neighborhood. Since the present invention has a very simple configuration, the optical adjustment is easier, and the device becomes compact in size. Furthermore, since the beam is slantly incident with respect to the irradiated body, the return beam can be prevented.
    Type: Application
    Filed: September 24, 2002
    Publication date: May 8, 2003
    Inventors: Koichiro Tanaka, Hidekazu Miyairi, Aiko Shiga, Akihisa Shimomura, Atsuo Isobe