Patents by Inventor Shogo Mada

Shogo Mada 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: 10192877
    Abstract: A mesa structure is formed over a substrate. An alternating stack of insulating layers and spacer material layers having a total height of approximately double the height of the mesa structure is formed over the substrate and the mesa structure. The spacer material layers are formed as, or are replaced with, electrically conductive layers. Portions of the alternating stack are removed from above the mesa structure by a planarization process. Stepped surfaces can be concurrently formed in a first terrace region overlying the mesa structure and in a second terrace region located at an opposite side of a memory array region of the alternating stack. A pair of level shifted stepped surfaces is formed. Contacts to the alternating stack can reach down only to the lowest surface of the pair of level shifted stepped surfaces, and can be shorter than the alternating stack.
    Type: Grant
    Filed: March 7, 2017
    Date of Patent: January 29, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Naoto Norizuki, Yasuchika Okizumi, Shogo Mada, Hiroyuki Ogawa
  • Publication number: 20180261611
    Abstract: A mesa structure is formed over a substrate. An alternating stack of insulating layers and spacer material layers having a total height of approximately double the height of the mesa structure is formed over the substrate and the mesa structure. The spacer material layers are formed as, or are replaced with, electrically conductive layers. Portions of the alternating stack are removed from above the mesa structure by a planarization process. Stepped surfaces can be concurrently formed in a first terrace region overlying the mesa structure and in a second terrace region located at an opposite side of a memory array region of the alternating stack. A pair of level shifted stepped surfaces is formed. Contacts to the alternating stack can reach down only to the lowest surface of the pair of level shifted stepped surfaces, and can be shorter than the alternating stack.
    Type: Application
    Filed: March 7, 2017
    Publication date: September 13, 2018
    Inventors: Naoto NORIZUKI, Yasuchika OKIZUMI, Shogo MADA, Hiroyuki OGAWA
  • Publication number: 20180061850
    Abstract: A mesa structure is formed over peripheral devices on a substrate. An alternating stack of insulating layers and spacer material layers is formed over the substrate and the mesa structure. A region of the alternating stack overlying the mesa structure is removed to provide a region in which the layers in the alternating stack extend along a non-horizontal direction that is parallel to the dielectric sidewall of the mesa structure. Memory stack structures and backside contact via structures are formed through another region of the alternating stack that includes horizontally-extending portions of the layers within the alternating stack. The spacer material layers are provided as, or are replaced with, electrically conductive layers. Top surfaces of portions of the electrically conductive layers that extend parallel to the dielectric sidewall of the mesa structure can be contacted by word line contact via structures.
    Type: Application
    Filed: August 30, 2016
    Publication date: March 1, 2018
    Inventors: Shogo MADA, Akira TAKAHASHI, Motoki UMEYAMA
  • Patent number: 9905573
    Abstract: A mesa structure is formed over peripheral devices on a substrate. An alternating stack of insulating layers and spacer material layers is formed over the substrate and the mesa structure. A region of the alternating stack overlying the mesa structure is removed to provide a region in which the layers in the alternating stack extend along a non-horizontal direction that is parallel to the dielectric sidewall of the mesa structure. Memory stack structures and backside contact via structures are formed through another region of the alternating stack that includes horizontally-extending portions of the layers within the alternating stack. The spacer material layers are provided as, or are replaced with, electrically conductive layers. Top surfaces of portions of the electrically conductive layers that extend parallel to the dielectric sidewall of the mesa structure can be contacted by word line contact via structures.
    Type: Grant
    Filed: August 30, 2016
    Date of Patent: February 27, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Shogo Mada, Akira Takahashi, Motoki Umeyama