Patents by Inventor Tomohiko Kudo

Tomohiko Kudo 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: 20230011948
    Abstract: Disclosed herein is a method that includes epitaxially growing SiGe layer on a silicon substrate, etching the SiGe layer and the silicon substrate to form an active region covered with the SiGe layer, first etching the SiGe layer formed on a first region of the active region without etching the SiGe layer formed on a second region of the active region to form a first trench, and second etching the SiGe layer remaining on an inner wall of the first trench.
    Type: Application
    Filed: July 7, 2021
    Publication date: January 12, 2023
    Applicant: Micron Technology, Inc.
    Inventor: Tomohiko Kudo
  • 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: 9076767
    Abstract: A semiconductor device includes a first-conductive type first pillar, a first dielectric surrounding the first pillar, a gate surrounding the dielectric, a second pillar underneath the first pillar, and a third pillar on a top of the first pillar. The second pillar has a second-conductive type region in a surface thereof except at least a part of a contact surface with the first pillar, and a first-conductive type region surrounded by the second-conductive type region. The third pillar has a second-conductive type impurity region in a surface thereof except a part of a contact surface with the first pillar, and a first-conductive type region therein and surrounded by the second-conductive type region of the third pillar. The first-conductive type region of each of the second and third pillars has a length greater than that of a depletion layer extending from a base of the second-conductive type region of one of the second and third pillars.
    Type: Grant
    Filed: September 5, 2014
    Date of Patent: July 7, 2015
    Assignee: UNISANTIS ELECTRONICS SINGAPORE PTE LTD.
    Inventors: Fujio Masuoka, Tomohiko Kudo
  • Publication number: 20150001614
    Abstract: A semiconductor device includes a first-conductive type first pillar, a first dielectric surrounding the first pillar, a gate surrounding the dielectric, a second pillar underneath the first pillar, and a third pillar on a top of the first pillar. The second pillar has a second-conductive type region in a surface thereof except at least a part of a contact surface with the first pillar, and a first-conductive type region surrounded by the second-conductive type region. The third pillar has a second-conductive type impurity region in a surface thereof except a part of a contact surface with the first pillar, and a first-conductive type region therein and surrounded by the second-conductive type region of the third pillar. The first-conductive type region of each of the second and third pillars has a length greater than that of a depletion layer extending from a base of the second-conductive type region of one of the second and third pillars.
    Type: Application
    Filed: September 5, 2014
    Publication date: January 1, 2015
    Inventors: Fujio MASUOKA, Tomohiko KUDO
  • Patent number: 8901640
    Abstract: The object of the invention is to provide a semiconductor device realizing high-speed operation of surrounding gate transistors (SGTs), which are three-dimensional semiconductors, by increasing the ON current of the SGTs. This object is achieved by a semiconductor element being provided in which a source, a drain and a gate are positioned in layers on a substrate, the semiconductor element being provided with: a silicon column; an insulating body surrounding the side surface of the silicon column; a gate surrounding the insulating body; a source region positioned above or below the silicon column; and a drain region positioned below or above the silicon column; wherein the contact surface of the silicon column with the source region is smaller than the contact surface of the silicon column with the drain region.
    Type: Grant
    Filed: November 11, 2010
    Date of Patent: December 2, 2014
    Assignee: Unisantis Electronics Singapore PTE Ltd.
    Inventors: Fujio Masuoka, Tomohiko Kudo
  • Patent number: 8896056
    Abstract: It is intended to solve a problem of increase in power consumption and reduction in operating speed due to an increase in parasitic capacitance of a surrounding gate transistor (SGT) as a three-dimensional semiconductor device, to provide an SGT achieving an increase in speed and power consumption reduction in a semiconductor circuit. The semiconductor device comprises a second-conductive type impurity region (510) formed in a part of a first-conductive type semiconductor substrate (100), a first silicon pillar (810) of an arbitrary cross-sectional shape formed on the second-conductive type impurity region, a first insulating body (310) surrounding a part of a surface of the first silicon pillar, a gate (210) surrounding the first insulating body, and a second silicon pillar (820) which is formed on the first silicon pillar and which includes a second-conductive type impurity region (540).
    Type: Grant
    Filed: February 11, 2010
    Date of Patent: November 25, 2014
    Assignee: Unisantis Electronics Singapore Pte Ltd.
    Inventors: Fujio Masuoka, Tomohiko Kudo
  • Patent number: 8860128
    Abstract: A semiconductor device includes a first pillar, a second pillar underneath the first pillar, and a third pillar on a top of the first pillar. The second pillar has a second-conductive type region in a surface thereof except at least a part of a contact surface region with the first pillar, and a first-conductive type region therein and surrounded by the second-conductive type region. The third pillar has a second-conductive type region in a surface thereof except at least a part of a contact surface region with the first pillar, and a first-conductive type region therein and surrounded by the second-conductive type region. The first-conductive type region of each of the second pillar and the third pillar has a length greater than that of a depletion layer extending from a base portion of the second-conductive type region of a respective one of the second pillar and the third pillar.
    Type: Grant
    Filed: July 2, 2013
    Date of Patent: October 14, 2014
    Assignee: Unisantis Electronics Singapore Pte Ltd.
    Inventors: Fujio Masuoka, Tomohiko Kudo
  • Publication number: 20130341707
    Abstract: A semiconductor device includes a first pillar, a second pillar underneath the first pillar, and a third pillar on a top of the first pillar. The second pillar has a second-conductive type region in a surface thereof except at least a part of a contact surface region with the first pillar, and a first-conductive type region therein and surrounded by the second-conductive type region. The third pillar has a second-conductive type region in a surface thereof except at least a part of a contact surface region with the first pillar, and a first-conductive type region therein and surrounded by the second-conductive type region. The first-conductive type region of each of the second pillar and the third pillar has a length greater than that of a depletion layer extending from a base portion of the second-conductive type region of a respective one of the second pillar and the third pillar.
    Type: Application
    Filed: July 2, 2013
    Publication date: December 26, 2013
    Inventors: Fujio MASUOKA, Tomohiko KUDO
  • 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: 8502303
    Abstract: Provided is a semiconductor device which is capable of preventing an increase in power consumption of an SGT, i.e., a three-dimensional semiconductor transistor, due to an increase in off-leak current. The semiconductor device comprises: a first-conductive type first silicon pillar: a first dielectric surrounding a side surface of the first silicon pillar; a gate surrounding the dielectric; a second silicon pillar provided underneath the first silicon pillar; and a third silicon pillar provided on a top of the first silicon pillar. The second silicon pillar has a second-conductive type high-concentration impurity region formed in a surface thereof except at least a part of a contact surface region with the first silicon pillar, and a first-conductive type impurity region formed therein and surrounded by the second-conductive type high-concentration impurity region.
    Type: Grant
    Filed: May 26, 2010
    Date of Patent: August 6, 2013
    Assignee: Unisantis Electronics Singapore Pte Ltd.
    Inventors: Fujio Masuoka, Tomohiko Kudo
  • 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
  • Patent number: 8395208
    Abstract: It is an object to provide an SGT production method capable of obtaining a structure for reducing a resistance of a gate, a desired gate length, desired source and drain configurations and a desired diameter of a pillar-shaped semiconductor.
    Type: Grant
    Filed: May 23, 2012
    Date of Patent: March 12, 2013
    Assignee: Unisantis Electronics Singapore Pte Ltd.
    Inventors: Fujio Masuoka, Shintaro Arai, Hiroki Nakamura, Tomohiko Kudo
  • Publication number: 20130059423
    Abstract: Provided is a method of manufacturing a semiconductor device, including: forming an active region surrounded by an element isolation region in a substrate; forming a pair of gate trenches in the active region; forming a pair of gate electrodes by embedding a conductor in the gate trenches; forming an implanted layer by implanting ions into a substrate surface between the gate electrodes; and thermally diffusing impurities of the implanted layer at least to a depth of bottom portions of the gate trenches by a transient enhanced diffusion method to form a diffusion layer region between the gate electrodes at least to a depth of bottom portions of the gate electrodes.
    Type: Application
    Filed: August 24, 2012
    Publication date: March 7, 2013
    Applicant: ELPIDA MEMORY, INC.
    Inventors: Tomohiko KUDO, Kiyonori OYU
  • Publication number: 20120299068
    Abstract: It is an object to provide an SGT production method capable of obtaining a structure for reducing a resistance of a gate, a desired gate length, desired source and drain configurations and a desired diameter of a pillar-shaped semiconductor.
    Type: Application
    Filed: May 23, 2012
    Publication date: November 29, 2012
    Inventors: Fujio Masuoka, Shintaro Arai, Hiroki Nakamura, Tomohiko Kudo