Patents by Inventor Tomohiko Kitajima

Tomohiko Kitajima 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: 20210233779
    Abstract: Memory devices and methods of manufacturing memory devices are provided. The device and methods described suppress oxidation of metal layers exposed to ambient oxygen. After an opening is formed, a nitridation process occurs to nitridate the surface of the exposed metal layer inside the opening. The nitridated region formed on the surface of metal layer inside the opening works as a barrier layer for oxygen diffusion. In addition, the nitridated region works as an electrode for charge trap memory cells.
    Type: Application
    Filed: January 13, 2021
    Publication date: July 29, 2021
    Applicant: Applied Materials, Inc.
    Inventors: Chang Seok Kang, Tomohiko Kitajima, Sung-Kwan Kang
  • Publication number: 20210217773
    Abstract: Embodiments of the present disclosure provide an apparatus and methods for forming stair-like structures with accurate profiles and dimension control for manufacturing three dimensional (3D) stacked memory cell semiconductor devices. In one embodiment, a memory cell device includes a film stack comprising alternating pairs of dielectric layers and conductive structures horizontally formed on a substrate, and an opening formed in the film stack, wherein the opening is filled with a metal dielectric layer, a multi-layer structure and a center filling layer, wherein the metal dielectric layer in the opening is interfaced with the conductive structure.
    Type: Application
    Filed: March 26, 2021
    Publication date: July 15, 2021
    Inventors: Changseok KANG, Tomohiko KITAJIMA
  • Patent number: 10998329
    Abstract: Methods and apparatus for forming a plurality of nonvolatile memory cells are provided herein. In some embodiments, the method, for example, includes forming a plurality of nonvolatile memory cells, comprising forming, on a substrate, a stack of alternating layers of metal including a first layer of metal and a second layer of metal different from the first layer of metal; removing the first layer of metal to form spaces between the alternating layers of the second layer of metal; and one of depositing a first layer of material to partially fill the spaces to leave air gaps therein or depositing a second layer of material to fill the spaces.
    Type: Grant
    Filed: July 22, 2019
    Date of Patent: May 4, 2021
    Assignee: APPLIED MATERIALS, INC.
    Inventors: Takehito Koshizawa, Mukund Srinivasan, Tomohiko Kitajima, Chang Seok Kang, Sung-Kwan Kang, Gill Y. Lee, Susmit Singha Roy
  • Publication number: 20210118691
    Abstract: Methods of etching film stacks to form gaps of uniform width are described. A film stack is etched through a hardmask. A conformal liner is deposited in the gap. The bottom of the liner is removed. The film stack is selectively etched relative to the liner. The liner is removed. The method may be repeated to a predetermined depth.
    Type: Application
    Filed: December 30, 2020
    Publication date: April 22, 2021
    Applicant: Applied Materials, Inc.
    Inventors: Shishi Jiang, Pramit Manna, Bo Qi, Abhijit Basu Mallick, Rui Cheng, Tomohiko Kitajima, Harry S. Whitesell, Huiyuan Wang
  • Patent number: 10964717
    Abstract: Methods and apparatus for forming a plurality of nonvolatile memory cells are provided herein. In some embodiments, the method, for example, includes forming, on a substrate, a stack of alternating layers including a first layer of material and a second layer of material different from the first layer of material; forming a memory hole in the stack of alternating layers of the first layer of material and the second layer of material; depositing a layer of blocking oxide on sides defining the memory hole; depositing a layer of silicon atop the layer of blocking oxide to form a silicon channel; deposit core oxide to fill the silicon channel; removing the first layer of material to form spaces between the alternating layers of the second material; and one of depositing a third layer of material to partially fill the spaces to leave air gaps therein or depositing a fourth layer of material to fill the spaces.
    Type: Grant
    Filed: August 1, 2019
    Date of Patent: March 30, 2021
    Assignee: APPLIED MATERIALS, INC.
    Inventors: Sung-Kwan Kang, Gill Lee, Chang Seok Kang, Tomohiko Kitajima
  • Patent number: 10886140
    Abstract: Methods of etching film stacks to from gaps of uniform width are described. A film stack is etched through a hardmask. A conformal liner is deposited in the gap. The bottom of the liner is removed. The film stack is selectively etched relative to the liner. The liner is removed. The method may be repeated to a predetermined depth.
    Type: Grant
    Filed: July 26, 2019
    Date of Patent: January 5, 2021
    Assignee: Applied Materials, Inc.
    Inventors: Shishi Jiang, Pramit Manna, Bo Qi, Abhijit Basu Mallick, Rui Cheng, Tomohiko Kitajima, Harry S. Whitesell, Huiyuan Wang
  • Publication number: 20200373310
    Abstract: Methods and apparatus for forming a plurality of nonvolatile memory cells are provided herein. In some embodiments, the method, for example, includes forming a plurality of nonvolatile memory cells, comprising forming, on a substrate, a stack of alternating layers of metal including a first layer of metal and a second layer of metal different from the first layer of metal; removing the first layer of metal to form spaces between the alternating layers of the second layer of metal; and one of depositing a first layer of material to partially fill the spaces to leave air gaps therein or depositing a second layer of material to fill the spaces.
    Type: Application
    Filed: July 22, 2019
    Publication date: November 26, 2020
    Inventors: Takehito Koshizawa, Mukund Srinivasan, Tomohiko Kitajima, Chang Seok Kang, Sung-Kwan Kang, Gill Y. Lee, Susmit Singha Roy
  • Publication number: 20200312874
    Abstract: Methods of manufacturing memory devices are provided. The methods decrease the thickness of the first layers and increase the thickness of the second layers. Semiconductor devices are described having a film stack comprising alternating nitride and second layers in a first portion of the device, the alternating nitride and second layers of the film stack having a nitride:oxide thickness ratio (Nf:Of); and a memory stack comprising alternating word line and second layers in a second portion of the device, the alternating word line and second layers of the memory stack having a word line:oxide thickness ratio (Wm:Om), wherein 0.1(Wm:Om)<Nf:Of<0.95(Wm:Om).
    Type: Application
    Filed: March 30, 2020
    Publication date: October 1, 2020
    Applicant: Applied Materials, Inc.
    Inventors: Chang Seok Kang, Tomohiko Kitajima, Mukund Srinivasan, Sanjay Natarajan
  • Publication number: 20200251151
    Abstract: Memory devices are described. The memory devices include a plurality of bit lines extending through a stack of alternating memory layers and dielectric layers. Each of the memory layers comprises a single crystalline-like silicon layer and includes a first word line, a second word line, a first capacitor, and a second capacitor. Methods of forming stacked memory devices are also described.
    Type: Application
    Filed: February 3, 2020
    Publication date: August 6, 2020
    Applicant: Applied Materials, Inc.
    Inventors: Chang Seok Kang, Tomohiko Kitajima, Gill Yong Lee, Sanjay Natarajan, Sung-Kwan Kang, Lequn Liu
  • Publication number: 20200235122
    Abstract: Methods and apparatus for forming a plurality of nonvolatile memory cells are provided herein. In some embodiments, the method, for example, includes forming, on a substrate, a stack of alternating layers including a first layer of material and a second layer of material different from the first layer of material; forming a memory hole in the stack of alternating layers of the first layer of material and the second layer of material; depositing a layer of blocking oxide on sides defining the memory hole; depositing a layer of silicon atop the layer of blocking oxide to form a silicon channel; deposit core oxide to fill the silicon channel; removing the first layer of material to form spaces between the alternating layers of the second material; and one of depositing a third layer of material to partially fill the spaces to leave air gaps therein or depositing a fourth layer of material to fill the spaces.
    Type: Application
    Filed: August 1, 2019
    Publication date: July 23, 2020
    Inventors: SUNG-KWAN KANG, GILL LEE, CHANG SEOK KANG, TOMOHIKO KITAJIMA
  • Publication number: 20200203373
    Abstract: Embodiments of the present disclosure provide an apparatus and methods for forming stair-like structures with accurate profiles and dimension control for manufacturing three dimensional (3D) stacked memory cell semiconductor devices. In one embodiment, a memory cell device includes a film stack comprising alternating pairs of dielectric layers and conductive structures horizontally formed on a substrate, and an opening formed in the film stack, wherein the opening is filled with a metal dielectric layer, a multi-layer structure and a center filling layer, wherein the metal dielectric layer in the opening is interfaced with the conductive structure.
    Type: Application
    Filed: October 18, 2019
    Publication date: June 25, 2020
    Inventors: ChangSeok KANG, Tomohiko KITAJIMA
  • Patent number: 10651098
    Abstract: A method of controlling polishing includes storing a base measurement, the base measurement being a measurement of a substrate after deposition of at least one layer overlying a semiconductor wafer and before deposition of an outer layer over the at least one layer, after deposition of the outer layer over the at least one layer and during polishing of the outer layer on substrate, receiving a sequence of raw measurements of the substrate from an in-situ monitoring system, normalizing each raw measurement in the sequence of raw measurement to generate a sequence of normalized measurements using the raw measurement and the base measurement, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on at least the sequence of normalized measurements.
    Type: Grant
    Filed: June 3, 2016
    Date of Patent: May 12, 2020
    Assignee: Applied Materials, Inc.
    Inventors: Tomohiko Kitajima, Jeffrey Drue David, Jun Qian, Taketo Sekine, Garlen C. Leung, Sidney P. Huey
  • Publication number: 20200035505
    Abstract: Methods of etching film stacks to from gaps of uniform width are described. A film stack is etched through a hardmask. A conformal liner is deposited in the gap. The bottom of the liner is removed. The film stack is selectively etched relative to the liner. The liner is removed. The method may be repeated to a predetermined depth.
    Type: Application
    Filed: July 26, 2019
    Publication date: January 30, 2020
    Inventors: Shishi Jiang, Pramit Manna, Bo Qi, Abhijit Basu Mallick, Rui Cheng, Tomohiko Kitajima, Harry S. Whitesell, Huiyuan Wang
  • Patent number: 10229842
    Abstract: A buff module and method for using the same are provided. In one embodiment, a buff module includes housing having an interior volume, a plurality of drive rollers and a pair of buff heads. The drive rollers are arranged to rotate a substrate within the interior volume on a substantially horizontal axis. The buff heads are disposed in the housing, each buff head rotatable on an axis substantially aligned with the horizontal axis and movable to a position substantially parallel with the horizontal axis.
    Type: Grant
    Filed: July 26, 2013
    Date of Patent: March 12, 2019
    Assignee: Applied Materials, Inc.
    Inventors: Clinton Sakata, Hui Chen, Jim K. Atkinson, Tomohiko Kitajima, Brian J. Brown
  • Patent number: 9811077
    Abstract: A method of controlling polishing includes storing a base spectrum, the base spectrum being a spectrum of light reflected from a substrate after deposition of a deposited dielectric layers overlying a metallic layer or semiconductor wafer and before deposition of a non-metallic layer over the plurality of deposited dielectric layer. After deposition of the non-metallic layer and during polishing of the non-metallic layer on the substrate, measurements of a sequence of raw spectra of light reflected the substrate during polishing are received from an in-situ optical monitoring system. Each raw spectrum is normalized to generate a sequence of normalized spectra using the raw spectrum and the base spectrum. At least one of a polishing endpoint or an adjustment for a polishing rate is determined based on at least one normalized predetermined spectrum from the sequence of normalized spectra.
    Type: Grant
    Filed: July 16, 2014
    Date of Patent: November 7, 2017
    Assignee: Applied Materials, Inc.
    Inventors: Tomohiko Kitajima, Jeffrey Drue David, Jun Qian, Taketo Sekine, Garlen C. Leung, Sidney P. Huey
  • Publication number: 20160284615
    Abstract: A method of controlling polishing includes storing a base measurement, the base measurement being a measurement of a substrate after deposition of at least one layer overlying a semiconductor wafer and before deposition of an outer layer over the at least one layer, after deposition of the outer layer over the at least one layer and during polishing of the outer layer on substrate, receiving a sequence of raw measurements of the substrate from an in-situ monitoring system, normalizing each raw measurement in the sequence of raw measurement to generate a sequence of normalized measurements using the raw measurement and the base measurement, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on at least the sequence of normalized measurements.
    Type: Application
    Filed: June 3, 2016
    Publication date: September 29, 2016
    Applicant: Applied Materials, Inc.
    Inventors: Tomohiko Kitajima, Jeffrey Drue David, Jun Qian, Taketo Sekine, Garlen C. Leung, Sidney P. Huey
  • Patent number: 9362186
    Abstract: A method of controlling polishing includes storing a base measurement, the base measurement being an eddy current measurement of a substrate after deposition of at least one layer overlying a semiconductor wafer and before deposition of a conductive layer over the at least one layer, after deposition of the conductive layer over the at least one layer and during polishing of the conductive layer on substrate, receiving a sequence of raw measurements of the substrate from an in-situ eddy current monitoring system, normalizing each raw measurement in the sequence of raw measurement to generate a sequence of normalized measurements using the raw measurement and the base measurement, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on at least the sequence of normalized measurements.
    Type: Grant
    Filed: July 15, 2015
    Date of Patent: June 7, 2016
    Assignee: Applied Materials, Inc.
    Inventors: Tomohiko Kitajima, Jeffrey Drue David, Jun Qian, Taketo Sekine, Garlen C. Leung, Sidney P. Huey
  • Publication number: 20160020157
    Abstract: A method of controlling polishing includes storing a base measurement, the base measurement being an eddy current measurement of a substrate after deposition of at least one layer overlying a semiconductor wafer and before deposition of a conductive layer over the at least one layer, after deposition of the conductive layer over the at least one layer and during polishing of the conductive layer on substrate, receiving a sequence of raw measurements of the substrate from an in-situ eddy current monitoring system, normalizing each raw measurement in the sequence of raw measurement to generate a sequence of normalized measurements using the raw measurement and the base measurement, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on at least the sequence of normalized measurements.
    Type: Application
    Filed: July 15, 2015
    Publication date: January 21, 2016
    Inventors: Tomohiko Kitajima, Jeffrey Drue David, Jun Qian, Taketo Sekine, Garlen C. Leung, Sidney P. Huey
  • Publication number: 20160018815
    Abstract: A method of controlling polishing includes storing a base spectrum, the base spectrum being a spectrum of light reflected from a substrate after deposition of a deposited dielectric layers overlying a metallic layer or semiconductor wafer and before deposition of a non-metallic layer over the plurality of deposited dielectric layer. After deposition of the non-metallic layer and during polishing of the non-metallic layer on the substrate, measurements of a sequence of raw spectra of light reflected the substrate during polishing are received from an in-situ optical monitoring system. Each raw spectrum is normalized to generate a sequence of normalized spectra using the raw spectrum and the base spectrum. At least one of a polishing endpoint or an adjustment for a polishing rate is determined based on at least one normalized predetermined spectrum from the sequence of normalized spectra.
    Type: Application
    Filed: July 16, 2014
    Publication date: January 21, 2016
    Inventors: Tomohiko Kitajima, Jeffrey Drue David, Jun Qian, Taketo Sekine, Garlen C. Leung, Sidney P. Huey
  • Patent number: 9005999
    Abstract: Methods for chemical mechanical polishing (CMP) of semiconductor substrates, and more particularly to temperature control during such chemical mechanical polishing are provided. In one aspect, the method comprises polishing the substrate with a polishing surface during a polishing process to remove a portion of the conductive material, repeatedly monitoring a temperature of the polishing surface during the polishing process, and exposing the polishing surface to a rate quench process in response to the monitored temperature so as to achieve a target value for the monitored temperature during the polishing process.
    Type: Grant
    Filed: June 30, 2012
    Date of Patent: April 14, 2015
    Assignee: Applied Materials, Inc.
    Inventors: Kun Xu, Jimin Zhang, David H. Mai, Stephen Jew, Shih-Haur Walters Shen, Zhihong Wang, Thomas H. Osterheld, Wen-Chiang Tu, Gary Ka Ho Lam, Tomohiko Kitajima