Patents by Inventor Daisuke Tsurumi

Daisuke Tsurumi 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: 8884353
    Abstract: A semiconductor memory device includes a source region, a drain region, a channel region, a charge storage layer, and a control gate electrode. The source region and drain region are formed separately from each other in a surface of a semiconductor substrate. The channel region is formed in the semiconductor substrate and located between the source region and the drain region. The charge storage layer is formed on the channel region with a first insulating film interposed therebetween. The control gate electrode is formed on the charge storage layer with a second insulating film interposed therebetween. The control gate has an upper corner portion rounded with a radius of curvature of 5 nm or more.
    Type: Grant
    Filed: April 22, 2011
    Date of Patent: November 11, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Tsurumi, Mitsuhiro Noguchi, Haruhiko Koyama
  • Publication number: 20110193155
    Abstract: A semiconductor memory device includes a source region, a drain region, a channel region, a charge storage layer, and a control gate electrode. The source region and drain region are formed separately from each other in a surface of a semiconductor substrate. The channel region is formed in the semiconductor substrate and located between the source region and the drain region. The charge storage layer is formed on the channel region with a first insulating film interposed therebetween. The control gate electrode is formed on the charge storage layer with a second insulating film interposed therebetween. The control gate has an upper corner portion rounded with a radius of curvature of 5 nm or more.
    Type: Application
    Filed: April 22, 2011
    Publication date: August 11, 2011
    Inventors: Daisuke TSURUMI, Mitsuhiro Noguchi, Haruhiko Koyama
  • Patent number: 7952132
    Abstract: A semiconductor memory device includes a source region, a drain region, a channel region, a charge storage layer, and a control gate electrode. The source region and drain region are formed separately from each other in a surface of a semiconductor substrate. The channel region is formed in the semiconductor substrate and located between the source region and the drain region. The charge storage layer is formed on the channel region with a first insulating film interposed therebetween. The control gate electrode is formed on the charge storage layer with a second insulating film interposed therebetween. The control gate has an upper corner portion rounded with a radius of curvature of 5 nm or more.
    Type: Grant
    Filed: December 9, 2009
    Date of Patent: May 31, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Tsurumi, Mitsuhiro Noguchi, Haruhiko Koyama
  • Publication number: 20100084703
    Abstract: A semiconductor memory device includes a source region, a drain region, a channel region, a charge storage layer, and a control gate electrode. The source region and drain region are formed separately from each other in a surface of a semiconductor substrate. The channel region is formed in the semiconductor substrate and located between the source region and the drain region. The charge storage layer is formed on the channel region with a first insulating film interposed therebetween. The control gate electrode is formed on the charge storage layer with a second insulating film interposed therebetween. The control gate has an upper corner portion rounded with a radius of curvature of 5 nm or more.
    Type: Application
    Filed: December 9, 2009
    Publication date: April 8, 2010
    Inventors: Daisuke TSURUMI, Mitsuhiro Noguchi, Haruhiko Koyama
  • Patent number: 7652319
    Abstract: A semiconductor memory device includes a source region, a drain region, a channel region, a charge storage layer, and a control gate electrode. The source region and drain region are formed separately from each other in a surface of a semiconductor substrate. The channel region is formed in the semiconductor substrate and located between the source region and the drain region. The charge storage layer is formed on the channel region with a first insulating film interposed therebetween. The control gate electrode is formed on the charge storage layer with a second insulating film interposed therebetween. The control gate has an upper corner portion rounded with a radius of curvature of 5 nm or more.
    Type: Grant
    Filed: November 15, 2007
    Date of Patent: January 26, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Tsurumi, Mitsuhiro Noguchi, Haruhiko Koyama
  • Publication number: 20080116503
    Abstract: A semiconductor memory device includes a source region, a drain region, a channel region, a charge storage layer, and a control gate electrode. The source region and drain region are formed separately from each other in a surface of a semiconductor substrate. The channel region is formed in the semiconductor substrate and located between the source region and the drain region. The charge storage layer is formed on the channel region with a first insulating film interposed therebetween. The control gate electrode is formed on the charge storage layer with a second insulating film interposed therebetween. The control gate has an upper corner portion rounded with a radius of curvature of 5 nm or more.
    Type: Application
    Filed: November 15, 2007
    Publication date: May 22, 2008
    Inventors: Daisuke Tsurumi, Mitsuhiro Noguchi, Haruhiko Koyama