Patents by Inventor Akira Hatsugai

Akira Hatsugai 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: 7473945
    Abstract: Disclosed is an optical semiconductor integrated circuit device has an opening portion in an insulating layer, which is formed in a light receiving region of a photodiode stepwise. Thus, a step of the opening portion is reduced, leading to an improvement of a step coverage of a light shadowing film formed on the insulating film so as to cover the insulating film. By the improvement of the step coverage of the opening portion, the light shadowing film located on a plane of the light shadowing film of the photodiode is not broken. A problem that a conventional light shadowing film is broken is solved in the photodiode for a blue laser beam.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: January 6, 2009
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tsuyoshi Takahashi, Katsuya Okabe, Akira Hatsugai
  • Patent number: 7235418
    Abstract: In an existing optical semiconductor integrated circuit device, a multi-layered wiring layer is formed on a top surface of a substrate. Therefore, a film thickness of an insulating layer on a top surface of a photodiode could be uniformed with difficulty. Thus there was a problem in the constitution of the insulating layer wherein light incidence was caused to fluctuate, and thereby a desired sensitivity to light could not be obtained. In an optical semiconductor integrated circuit device according to the present invention, after a multi-layered wiring layer is formed on a top surface of a substrate, an insulating layer on a top surface of an anti-reflection film of a photodiode is dry-etched to remove. At this time, a barrier metal layer is used as an etching stopper film. Thereby, in the invention, a manufacturing process can be simplified and owing to adoption of the dry etching miniaturization can be realized.
    Type: Grant
    Filed: September 27, 2004
    Date of Patent: June 26, 2007
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tsuyoshi Takahashi, Katsuya Okabe, Akira Hatsugai
  • Patent number: 7067347
    Abstract: In an existing optical semiconductor integrated circuit device, a silicon nitride film that is an anti-reflection film is used as an etching stopper film at the etching of an insulating film and by means of wet etching the insulating film is removed once for all. Accordingly, there is a problem in that the processing accuracy is poor. In an optical semiconductor integrated circuit device according to the present invention, after a multi-layered wiring layer is formed on a top surface of a silicon substrate, an insulating layer on a top surface of an anti-reflection film of a photodiode is removed by means of dry etching. At this time, a polycrystal silicon film is used as an etching stopper film. Thereby, in the photodiode according to the invention, although the dry etching is used, since a silicon nitride film that is an anti-reflection film is not over-etched, the dispersion of film thickness thereof can be inhibited from occurring.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: June 27, 2006
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tsuyoshi Takahashi, Katsuya Okabe, Akira Hatsugai
  • Publication number: 20050218417
    Abstract: Disclosed is an optical semiconductor integrated circuit device has an opening portion in an insulating layer, which is formed in a light receiving region of a photodiode stepwise. Thus, a step of the opening portion is reduced, leading to an improvement of a step coverage of a light shadowing film formed on the insulating film so as to cover the insulating film. By the improvement of the step coverage of the opening portion, the light shadowing film located on a plane of the light shadowing film of the photodiode is not broken. A problem that a conventional light shadowing film is broken is solved in the photodiode for a blue laser beam.
    Type: Application
    Filed: March 23, 2005
    Publication date: October 6, 2005
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Tsuyoshi Takahashi, Katsuya Okabe, Akira Hatsugai
  • Publication number: 20050118815
    Abstract: In an existing optical semiconductor integrated circuit device, a silicon nitride film that is an anti-reflection film is used as an etching stopper film at the etching of an insulating film and by means of wet etching the insulating film is removed once for all. Accordingly, there is a problem in that the processing accuracy is poor. In an optical semiconductor integrated circuit device according to the present invention, after a multi-layered wiring layer is formed on a top surface of a silicon substrate, an insulating layer on a top surface of an anti-reflection film of a photodiode is removed by means of dry etching. At this time, a polycrystal silicon film is used as an etching stopper film. Thereby, in the photodiode according to the invention, although the dry etching is used, since a silicon nitride film that is an anti-reflection film is not over-etched, the dispersion of film thickness thereof can be inhibited from occurring.
    Type: Application
    Filed: September 24, 2004
    Publication date: June 2, 2005
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Tsuyoshi Takahashi, Katsuya Okabe, Akira Hatsugai
  • Publication number: 20050106767
    Abstract: In an existing optical semiconductor integrated circuit device, a multi-layered wiring layer is formed on a top surface of a substrate. Therefore, a film thickness of an insulating layer on a top surface of a photodiode could be uniformed with difficulty. Thus there was a problem in the constitution of the insulating layer wherein light incidence was caused to fluctuate, and thereby a desired sensitivity to light could not be obtained. In an optical semiconductor integrated circuit device according to the present invention, after a multi-layered wiring layer is formed on a top surface of a substrate, an insulating layer on a top surface of an anti-reflection film of a photodiode is dry-etched to remove. At this time, a barrier metal layer is used as an etching stopper film. Thereby, in the invention, a manufacturing process can be simplified and owing to adoption of the dry etching miniaturization can be realized.
    Type: Application
    Filed: September 27, 2004
    Publication date: May 19, 2005
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Tsuyoshi Takahashi, Katsuya Okabe, Akira Hatsugai
  • Patent number: 6114744
    Abstract: A lead electrode is formed to expose an active base region. A lead electrode for an emitter electrode is formed on the lead electrode in an emitter region, through an insulating film. The insulating film on the lead electrode is then etched to form a contact hole. After that, the emitter contact hole is formed to expose the lead electrode. Also, a silicon nitride film SN is interposed between the lead electrode and insulating film and between the lead electrode and LOCOS oxide film each to decrease resistance of the lead electrodes.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: September 5, 2000
    Assignee: Sanyo Electric Company
    Inventors: Masayuki Kawaguchi, Yasunari Tagami, Hirotsugu Hata, Akira Hatsugai