Patents by Inventor Kavitha Devi Buddharaju

Kavitha Devi Buddharaju 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: 20160308013
    Abstract: A semiconductor device production method includes preparing a first structure having a first planar semiconductor layer, and a first columnar semiconductor layer on the first planar semiconductor layer. A first high concentration semiconductor layer is formed in a lower region of the first columnar semiconductor layer and in a region of the first planar semiconductor layer below the first columnar semiconductor layer. An insulating layer, a metal film, and a semiconductor film are sequentially formed on the first structure, and the semiconductor film, the metal film, and the insulating layer are sequentially etched with each leaving a sidewall shape on the sidewall on the first columnar semiconductor layer following etching. Another semiconductor film is then formed on the sidewall shape after etching the insulating film.
    Type: Application
    Filed: June 24, 2016
    Publication date: October 20, 2016
    Inventors: Fujio MASUOKA, Hiroki NAKAMURA, Shintaro ARAI, Tomohiko KUDO, King-Jien CHUI, Yisuo LI, Yu JIANG, Xiang LI, Zhixian CHEN, Nansheng SHEN, Vladimir BLIZNETSOV, Kavitha Devi BUDDHARAJU, Navab SINGH
  • Publication number: 20150357428
    Abstract: The semiconductor device according to the present invention is an nMOS SGT and is composed of a first n+ type silicon layer, a first gate electrode containing metal and a second n+ type silicon layer arranged on the surface of a first columnar silicon layer positioned vertically on a first planar silicon layer. Furthermore, a first insulating film is positioned between the first gate electrode and the first planar silicon layer, and a second insulating film is positioned on the top surface of the first gate electrode. In addition, the first gate electrode containing metal is surrounded by the first n+ type silicon layer, the second n+ type silicon layer, the first insulating film and the second insulating film.
    Type: Application
    Filed: August 20, 2015
    Publication date: December 10, 2015
    Inventors: Fujio MASUOKA, Hiroki NAKAMURA, Shintaro ARAI, Tomohiko KUDO, King-Jien CHUI, Yisuo LI, Yu JIANG, Xiang LI, Zhixian CHEN, Nansheng SHEN, Vladimir BLIZNETSOV, Kavitha Devi BUDDHARAJU, Navab SINGH
  • Patent number: 9153697
    Abstract: The semiconductor device according to the present invention is an nMOS SGT and is composed of a first n+ type silicon layer, a first gate electrode containing metal and a second n+ type silicon layer arranged on the surface of a first columnar silicon layer positioned vertically on a first planar silicon layer. Furthermore, a first insulating film is positioned between the first gate electrode and the first planar silicon layer, and a second insulating film is positioned on the top surface of the first gate electrode. In addition, the first gate electrode containing metal is surrounded by the first n+ type silicon layer, the second n+ type silicon layer, the first insulating film and the second insulating film.
    Type: Grant
    Filed: May 26, 2011
    Date of Patent: October 6, 2015
    Assignee: UNISANTIS ELECTRONICS SINGAPORE PTE LTD.
    Inventors: Fujio Masuoka, Hiroki Nakamura, Shintaro Arai, Tomohiko Kudo, King-Jien Chui, Yisuo Li, Yu Jiang, Xiang Li, Zhixian Chen, Nansheng Shen, Vladimir Bliznetsov, Kavitha Devi Buddharaju, Navab Singh
  • Patent number: 8609494
    Abstract: The semiconductor device includes: a columnar silicon layer on the planar silicon layer; a first n+ type silicon layer formed in a bottom area of the columnar silicon layer; a second n+ type silicon layer formed in an upper region of the columnar silicon layer; a gate insulating film formed in a perimeter of a channel region between the first and second n+ type silicon layers; a gate electrode formed in a perimeter of the gate insulating film, and having a first metal-silicon compound layer; an insulating film formed between the gate electrode and the planar silicon layer, an insulating film sidewall formed in an upper sidewall of the columnar silicon layer; a second metal-silicon compound layer formed in the planar silicon layer; and an electric contact formed on the second n+ type silicon layer.
    Type: Grant
    Filed: May 16, 2013
    Date of Patent: December 17, 2013
    Assignee: Unisantis Electronics Singapore Pte Ltd.
    Inventors: Fujio Masuoka, Hiroki Nakamura, Shintaro Arai, Tomohiko Kudo, Yu Jiang, King-Jien Chui, Yisuo Li, Xiang Li, Zhixian Chen, Nansheng Shen, Vladimir Bliznetsov, Kavitha Devi Buddharaju, Navab Singh
  • Patent number: 8563379
    Abstract: A method for producing a semiconductor device includes preparing a structure having a substrate, a planar semiconductor layer and a columnar semiconductor layer, forming a second drain/source region in the upper part of the columnar semiconductor layer, forming a contact stopper film and a contact interlayer film, and forming a contact layer on the second drain/source region. The step for forming the contact layer includes forming a pattern and etching the contact interlayer film to the contact stopper film using the pattern to form a contact hole for the contact layer and removing the contact stopper film remaining at the bottom of the contact hole by etching. The projection of the bottom surface of the contact hole onto the substrate is within the circumference of the projected profile of the contact stopper film formed on the top and side surface of the columnar semiconductor layer onto the substrate.
    Type: Grant
    Filed: December 10, 2012
    Date of Patent: October 22, 2013
    Assignee: Unisantis Electronics Singapore Pte Ltd.
    Inventors: Fujio Masuoka, Shintaro Arai, Hiroki Nakamura, Tomohiko Kudo, R. Ramana Murthy, Nansheng Shen, Kavitha Devi Buddharaju, Navab Singh
  • Publication number: 20130252413
    Abstract: The semiconductor device includes: a columnar silicon layer on the planar silicon layer; a first n+ type silicon layer formed in a bottom area of the columnar silicon layer; a second n+ type silicon layer formed in an upper region of the columnar silicon layer; a gate insulating film formed in a perimeter of a channel region between the first and second n+ type silicon layers; a gate electrode formed in a perimeter of the gate insulating film, and having a first metal-silicon compound layer; an insulating film formed between the gate electrode and the planar silicon layer, an insulating film sidewall formed in an upper sidewall of the columnar silicon layer; a second metal-silicon compound layer formed in the planar silicon layer; and an electric contact formed on the second n+ type silicon layer.
    Type: Application
    Filed: May 16, 2013
    Publication date: September 26, 2013
    Applicant: Unisantis Eletronics Singapore Pte.Ltd.
    Inventors: Fujio MASUOKA, Hiroki Nakamura, Shintaro Arai, Tomohiko Kudo, Yu Jiang, King-Jien Chui, Yisuo Li, Xiang Li, Zhixian Chen, Nansheng Shen, Vladimir Bliznetsov, Kavitha Devi Buddharaju, Navab Singh
  • Patent number: 8519475
    Abstract: A semiconductor device includes a first insulating film formed between a gate electrode and a first flat semiconductor layer, and a sidewall-shaped second insulating film formed to surround an upper sidewall of a first columnar silicon layer while contacting an upper surface of the gate electrode and to surround a sidewall of the gate electrode and the first insulating film. The semiconductor device further includes a metal-semiconductor compound formed on each of an upper surface of a first semiconductor layer of the second conductive type formed in the entirety or the upper portion of the first flat semiconductor layer, and an upper surface of the second semiconductor layer of the second conductive type formed in the upper portion of the first columnar semiconductor layer.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: August 27, 2013
    Assignee: Unisantis Electronics Singapore Pte Ltd.
    Inventors: Fujio Masuoka, Hiroki Nakamura, Shintaro Arai, Tomohiko Kudo, Navab Singh, Kavitha Devi Buddharaju, Shen Nansheng, Rukmani Devi Sayanthan
  • Patent number: 8486785
    Abstract: The semiconductor device includes: a columnar silicon layer on the planar silicon layer; a first n+ type silicon layer formed in a bottom area of the columnar silicon layer; a second n+ type silicon layer formed in an upper region of the columnar silicon layer; a gate insulating film formed in a perimeter of a channel region between the first and second n+ type silicon layers; a gate electrode formed in a perimeter of the gate insulating film, and having a first metal-silicon compound layer; an insulating film formed between the gate electrode and the planar silicon layer, an insulating film sidewall formed in an upper sidewall of the columnar silicon layer; a second metal-silicon compound layer formed in the planar silicon layer; and an electric contact formed on the second n+ type silicon layer.
    Type: Grant
    Filed: May 23, 2011
    Date of Patent: July 16, 2013
    Assignee: Unisantis Electronics Singapore Pte Ltd.
    Inventors: Fujio Masuoka, Hiroki Nakamura, Shintaro Arai, Tomohiko Kudo, Yu Jiang, King-Jien Chui, Yisuo Li, Xiang Li, Zhixian Chen, Nansheng Shen, Vladimir Bliznetsov, Kavitha Devi Buddharaju, Navab Singh
  • Patent number: 8466512
    Abstract: A method for producing a semiconductor device includes preparing a structure having a substrate, a planar semiconductor layer and a columnar semiconductor layer, forming a second drain/source region in the upper part of the columnar semiconductor layer, forming a contact stopper film and a contact interlayer film, and forming a contact layer on the second drain/source region. The step for forming the contact layer includes forming a pattern and etching the contact interlayer film to the contact stopper film using the pattern to form a contact hole for the contact layer and removing the contact stopper film remaining at the bottom of the contact hole by etching. The projection of the bottom surface of the contact hole onto the substrate is within the circumference of the projected profile of the contact stopper film formed on the top and side surface of the columnar semiconductor layer onto the substrate.
    Type: Grant
    Filed: August 18, 2010
    Date of Patent: June 18, 2013
    Assignee: Unisantis Electronics Singapore Pte Ltd.
    Inventors: Fujio Masuoka, Shintaro Arai, Hiroki Nakamura, Tomohiko Kudo, R. Ramana Murthy, Nansheng Shen, Kavitha Devi Buddharaju, Navab Singh
  • Publication number: 20120049252
    Abstract: A semiconductor device includes a first insulating film formed between a gate electrode and a first flat semiconductor layer, and a sidewall-shaped second insulating film formed to surround an upper sidewall of a first columnar silicon layer while contacting an upper surface of the gate electrode and to surround a sidewall of the gate electrode and the first insulating film. The semiconductor device further includes a metal-semiconductor compound formed on each of an upper surface of a first semiconductor layer of the second conductive type formed in the entirety or the upper portion of the first flat semiconductor layer, and an upper surface of the second semiconductor layer of the second conductive type formed in the upper portion of the first columnar semiconductor layer.
    Type: Application
    Filed: November 4, 2011
    Publication date: March 1, 2012
    Applicant: Unisantis Electronics Singapore PTE Ltd.
    Inventors: Fujio MASUOKA, Hiroki NAKAMURA, Shintaro ARAI, Tomohiko KUDO, Navab Singh, Kavitha Devi Buddharaju, Shen Nansheng, Rukmani Devi Sayanthan
  • Patent number: 8080458
    Abstract: A method of manufacturing a semiconductor device includes the steps of forming a first columnar semiconductor layer on a substrate forming a first flat semiconductor layer forming a first semiconductor layer of a second conductive type, and forming a first insulating film. The method further includes the steps of forming a gate insulating film and a gate electrode, forming a second semiconductor layer of the second conductive type, forming a semiconductor layer of a first conductive type and forming a metal-semiconductor compound. The first insulating film has a thickness larger than that of the gate insulating film formed around the first columnar silicon layer.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: December 20, 2011
    Assignee: Unisantis Electronics Singapore Pte. Ltd.
    Inventors: Fujio Masuoka, Hiroki Nakamura, Shintaro Arai, Tomohiko Kudo, Navab Singh, Kavitha Devi Buddharaju, Shen Nansheng, Rukmani Devi Sayanthan
  • Publication number: 20110303985
    Abstract: The semiconductor device includes: a columnar silicon layer on the planar silicon layer; a first n+ type silicon layer formed in a bottom area of the columnar silicon layer; a second n+ type silicon layer formed in an upper region of the columnar silicon layer; a gate insulating film formed in a perimeter of a channel region between the first and second n+ type silicon layers; a gate electrode formed in a perimeter of the gate insulating film, and having a first metal-silicon compound layer; an insulating film formed between the gate electrode and the planar silicon layer, an insulating film sidewall formed in an upper sidewall of the columnar silicon layer; a second metal-silicon compound layer formed in the planar silicon layer; and an electric contact formed on the second n+ type silicon layer.
    Type: Application
    Filed: May 23, 2011
    Publication date: December 15, 2011
    Inventors: Fujio Masuoka, Hiroki Nakamura, Shintaro Arai, Tomohiko Kudo, Yu Jiang, King-Jien Chui, Yisuo Li, Xiang Li, Zhixian Chen, Nansheng Shen, Vladimir Bliznetsov, Kavitha Devi Buddharaju, Navab Singh
  • Publication number: 20110303973
    Abstract: The semiconductor device according to the present invention is an nMOS SGT and is composed of a first n+ type silicon layer, a first gate electrode containing metal and a second n+ type silicon layer arranged on the surface of a first columnar silicon layer positioned vertically on a first planar silicon layer. Furthermore, a first insulating film is positioned between the first gate electrode and the first planar silicon layer, and a second insulating film is positioned on the top surface of the first gate electrode. In addition, the first gate electrode containing metal is surrounded by the first n+ type silicon layer, the second n+ type silicon layer, the first insulating film and the second insulating film.
    Type: Application
    Filed: May 26, 2011
    Publication date: December 15, 2011
    Inventors: Fujio Masuoka, Hiroki Nakamura, Shintaro Arai, Tomohiko Kudo, King-Jien Chui, Yisuo Li, Yu Jiang, Xiang Li, Zhixian Chen, Nansheng Shen, Vladimir Bliznetsov, Kavitha Devi Buddharaju, Navab Singh
  • Publication number: 20110042740
    Abstract: A method for producing a semiconductor device includes preparing a structure having a substrate, a planar semiconductor layer and a columnar semiconductor layer, forming a second drain/source region in the upper part of the columnar semiconductor layer, forming a contact stopper film and a contact interlayer film, and forming a contact layer on the second drain/source region. The step for forming the contact layer includes forming a pattern and etching the contact interlayer film to the contact stopper film using the pattern to form a contact hole for the contact layer and removing the contact stopper film remaining at the bottom of the contact hole by etching. The projection of the bottom surface of the contact hole onto the substrate is within the circumference of the projected profile of the contact stopper film formed on the top and side surface of the columnar semiconductor layer onto the substrate.
    Type: Application
    Filed: August 18, 2010
    Publication date: February 24, 2011
    Applicant: UNISANTIS ELECTRONICS (JAPAN) LTD.
    Inventors: Fujio MASUOKA, Shintaro ARAI, Hiroki NAKAMURA, Tomohiko KUDO, R. Ramana MURTHY, Nansheng SHEN, Kavitha Devi BUDDHARAJU, Navab SINGH
  • Publication number: 20100264485
    Abstract: This invention provides a method of manufacturing a semiconductor device, which comprises the steps of: forming a first columnar semiconductor layer on a first flat semiconductor layer; forming a first semiconductor layer of a second conductive type in a lower portion of the first columnar semiconductor layer; forming a first insulating film around a lower sidewall of the first columnar silicon layer; forming a gate insulating film and a gate electrode around the first columnar silicon layer; forming a sidewall-shaped second insulating film to surround an upper sidewall of the first columnar silicon layer; forming a semiconductor layer of a first conductive type between the first semiconductor layer of the second conductive type and a second semiconductor layer of the second conductive type; and forming a metal-semiconductor compound on an upper surface of the first semiconductor layer of the second conductive type.
    Type: Application
    Filed: April 16, 2010
    Publication date: October 21, 2010
    Inventors: Fujio Masuoka, Hiroki Nakamura, Shintaro Arai, Tomohiko Kudo, Navab Singh, Kavitha Devi Buddharaju, Shen Nansheng, Rukmani Devi Sayanthan