Patents by Inventor Yujiro Sakurada

Yujiro Sakurada 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: 20150287831
    Abstract: A semiconductor device includes an oxide semiconductor film, a source electrode, a drain electrode, a gate insulating film, a gate electrode, and an insulating film. The source electrode includes a region in contact with the oxide semiconductor film. The drain electrode includes a region in contact with the oxide semiconductor film. The gate insulating film is provided between the oxide semiconductor film and the gate electrode. The insulating film is provided over the gate electrode and over the gate insulating film. The insulating film includes a first portion and a second portion. The first portion includes a step portion. The second portion includes a non-step portion. The first portion includes a portion with a first thickness. The second portion includes a portion with a second thickness. The second thickness is larger than or equal to 1.0 time and smaller than or equal to 2.0 times the first thickness.
    Type: Application
    Filed: April 2, 2015
    Publication date: October 8, 2015
    Inventors: Tetsuhiro TANAKA, Yujiro SAKURADA, Yutaka OKAZAKI
  • Patent number: 8368082
    Abstract: A non-single-crystal semiconductor layer is formed over a substrate, and then a single crystal semiconductor layer is formed over part of the non-single-crystal semiconductor layer. Thus, a semiconductor element of a region which requires a large area (e.g. a pixel region in a display device) can be formed using the non-single-crystal semiconductor layer, and a semiconductor element of a region which requires high speed operation (e.g. a driver circuit region in a display device) can be formed using the single crystal semiconductor layer.
    Type: Grant
    Filed: October 27, 2011
    Date of Patent: February 5, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Tomokazu Yokoi, Yujiro Sakurada
  • Publication number: 20130023108
    Abstract: An insulating layer is formed on a surface of a semiconductor wafer which is to be a bond substrate and an embrittlement region is formed in the semiconductor wafer by irradiation with accelerated ions. Then, a base substrate and the semiconductor wafer are attached to each other. After that, the semiconductor wafer is divided at the embrittlement region by performing heat treatment and an SOI substrate including a semiconductor layer over the base substrate with the insulating layer interposed therebetween is formed. Before the SOI substrate is formed, heat treatment is performed on the semiconductor wafer at a temperature of higher than or equal to 1100° C. under a non-oxidizing atmosphere in which the concentration of impurities is reduced. In this manner, the planarity of the film formed on the semiconductor wafer when heat treatment is performed can be improved.
    Type: Application
    Filed: July 18, 2012
    Publication date: January 24, 2013
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Kazuya HANAOKA, Yujiro SAKURADA, Hideki TSUYA, Makoto FURUNO, Miku FUJITA
  • Publication number: 20120037903
    Abstract: A non-single-crystal semiconductor layer is formed over a substrate, and then a single crystal semiconductor layer is formed over part of the non-single-crystal semiconductor layer. Thus, a semiconductor element of a region which requires a large area (e.g. a pixel region in a display device) can be formed using the non-single-crystal semiconductor layer, and a semiconductor element of a region which requires high speed operation (e.g. a driver circuit region in a display device) can be formed using the single crystal semiconductor layer.
    Type: Application
    Filed: October 27, 2011
    Publication date: February 16, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Tomokazu YOKOI, Yujiro SAKURADA
  • Patent number: 8048771
    Abstract: A non-single-crystal semiconductor layer is formed over a substrate, and then a single crystal semiconductor layer is formed over part of the non-single-crystal semiconductor layer. Thus, a semiconductor element of a region which requires a large area (e.g. a pixel region in a display device) can be formed using the non-single-crystal semiconductor layer, and a semiconductor element of a region which requires high speed operation (e.g. a driver circuit region in a display device) can be formed using the single crystal semiconductor layer.
    Type: Grant
    Filed: November 21, 2008
    Date of Patent: November 1, 2011
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Tomokazu Yokoi, Yujiro Sakurada
  • Publication number: 20090134397
    Abstract: A non-single-crystal semiconductor layer is formed over a substrate, and then a single crystal semiconductor layer is formed over part of the non-single-crystal semiconductor layer. Thus, a semiconductor element of a region which requires a large area (e.g. a pixel region in a display device) can be formed using the non-single-crystal semiconductor layer, and a semiconductor element of a region which requires high speed operation (e.g. a driver circuit region in a display device) can be formed using the single crystal semiconductor layer.
    Type: Application
    Filed: November 21, 2008
    Publication date: May 28, 2009
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Tomokazu YOKOI, Yujiro Sakurada