Patents by Inventor Senaka Kanakamedala

Senaka Kanakamedala 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: 20210066347
    Abstract: A joint level dielectric material layer is formed over a first alternating stack of first insulating layers and first spacer material layers. A first memory opening is formed with a tapered sidewall of the joint level dielectric material layer. A second alternating stack of second insulating layers and second spacer material layers is formed over the joint level dielectric material layer. An inter-tier memory opening is formed, which includes a volume of an second memory opening that extends through the second alternating stack and a volume of the first memory opening. A memory film and a semiconductor channel are formed in the inter-tier memory opening with respective tapered portions overlying the tapered sidewall of the joint level dielectric material layer.
    Type: Application
    Filed: November 16, 2020
    Publication date: March 4, 2021
    Inventors: Monica Titus, Zhixin Cui, Senaka Kanakamedala, Yao-Sheng Lee, Chih-Yu Lee
  • Patent number: 10910272
    Abstract: A support substrate including a plurality of channels on a front side is provided. A cover layer is formed by anisotropically depositing a sacrificial cover material over the plurality of channels. Cavities laterally extend within the plurality of channels underneath a horizontally extending portion of the cover layer. An encapsulation layer is conformally deposited. First semiconductor devices, first metal interconnect structures, and first bonding pads are formed over a top surface of the encapsulation layer. A device substrate with second bonding pads is provided. The second bonding pads are bonded with the first bonding pads to form a bonded assembly. Peripheral portions of the encapsulation layer are removes and peripheral portions of the cover layer are physically exposed. The cover layer is removed employing an isotropic etch process by propagating an isotropic etchant through the cavities to separate the support substrate from the bonded assembly.
    Type: Grant
    Filed: October 22, 2019
    Date of Patent: February 2, 2021
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Fei Zhou, Senaka Kanakamedala, Raghuveer S Makala
  • Publication number: 20210028136
    Abstract: At least one polymer material may be employed to facilitate bonding between the semiconductor dies. Plasma treatment, formation of a blended polymer, or formation of polymer hairs may be employed to enhance bonding. Alternatively, air gaps can be formed by subsequently removing the polymer material to reduce capacitive coupling between adjacent bonding pads.
    Type: Application
    Filed: April 17, 2020
    Publication date: January 28, 2021
    Inventors: Ramy Nashed Bassely SAID, Senaka KANAKAMEDALA, Raghuveer S. MAKALA
  • Publication number: 20210028135
    Abstract: At least one polymer material may be employed to facilitate bonding between the semiconductor dies. Plasma treatment, formation of a blended polymer, or formation of polymer hairs may be employed to enhance bonding. Alternatively, air gaps can be formed by subsequently removing the polymer material to reduce capacitive coupling between adjacent bonding pads.
    Type: Application
    Filed: April 17, 2020
    Publication date: January 28, 2021
    Inventors: Ramy Nashed Bassely SAID, Senaka KANAKAMEDALA, Raghuveer S. MAKALA
  • Patent number: 10847408
    Abstract: A first semiconductor die and a second semiconductor die can be bonded in a manner that enhances alignment of bonding pads. Non-uniform deformation of a first wafer including first semiconductor dies can be compensated for by forming a patterned stress-generating film on a backside of the first wafer. Metallic bump portions can be formed on concave surfaces of metallic bonding pads by a selective metal deposition process to reduce gaps between pairs of bonded metallic bonding pads. Pad-to-pad pitch can be adjusted on a semiconductor die to match the pad-to-pad pitch of another semiconductor die employing a tilt-shift operation in a lithographic exposure tool. A chuck configured to provide non-uniform displacement across a wafer can be employed to hold a wafer in a contoured shape for bonding with another wafer in a matching contoured position. Independently height-controlled pins can be employed to hold a wafer in a non-planar configuration.
    Type: Grant
    Filed: January 31, 2019
    Date of Patent: November 24, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Raghuveer S. Makala, Senaka Kanakamedala, Yao-Sheng Lee, Jian Chen
  • Patent number: 10748925
    Abstract: A three-dimensional memory device includes a vertical semiconductor channel surrounding a vertical dielectric core. Laterally extending dielectric pegs structurally support the vertical semiconductor channel and the vertical dielectric core. The vertical semiconductor channel may be a single crystalline semiconductor channel.
    Type: Grant
    Filed: February 5, 2019
    Date of Patent: August 18, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Masanori Tsutsumi, Manabu Kakazu, Raghuveer S. Makala, Senaka Kanakamedala
  • Publication number: 20200251486
    Abstract: A three-dimensional memory device includes a vertical semiconductor channel surrounding a vertical dielectric core. Laterally extending dielectric pegs structurally support the vertical semiconductor channel and the vertical dielectric core. The vertical semiconductor channel may be a single crystalline semiconductor channel.
    Type: Application
    Filed: February 5, 2019
    Publication date: August 6, 2020
    Inventors: Masanori TSUTSUMI, Manabu KAKAZU, Raghuveer S. MAKALA, Senaka KANAKAMEDALA
  • Publication number: 20200251443
    Abstract: A first semiconductor die and a second semiconductor die can be bonded in a manner that enhances alignment of bonding pads. Non-uniform deformation of a first wafer including first semiconductor dies can be compensated for by forming a patterned stress-generating film on a backside of the first wafer. Metallic bump portions can be formed on concave surfaces of metallic bonding pads by a selective metal deposition process to reduce gaps between pairs of bonded metallic bonding pads. Pad-to-pad pitch can be adjusted on a semiconductor die to match the pad-to-pad pitch of another semiconductor die employing a tilt-shift operation in a lithographic exposure tool. A chuck configured to provide non-uniform displacement across a wafer can be employed to hold a wafer in a contoured shape for bonding with another wafer in a matching contoured position. Independently height-controlled pins can be employed to hold a wafer in a non-planar configuration.
    Type: Application
    Filed: January 31, 2019
    Publication date: August 6, 2020
    Inventors: Senaka KANAKAMEDALA, Raghuveer S. MAKALA, Yao-Sheng LEE, Jian CHEN
  • Publication number: 20200251374
    Abstract: A first semiconductor die and a second semiconductor die can be bonded in a manner that enhances alignment of bonding pads. Non-uniform deformation of a first wafer including first semiconductor dies can be compensated for by forming a patterned stress-generating film on a backside of the first wafer. Metallic bump portions can be formed on concave surfaces of metallic bonding pads by a selective metal deposition process to reduce gaps between pairs of bonded metallic bonding pads. Pad-to-pad pitch can be adjusted on a semiconductor die to match the pad-to-pad pitch of another semiconductor die employing a tilt-shift operation in a lithographic exposure tool. A chuck configured to provide non-uniform displacement across a wafer can be employed to hold a wafer in a contoured shape for bonding with another wafer in a matching contoured position. Independently height-controlled pins can be employed to hold a wafer in a non-planar configuration.
    Type: Application
    Filed: January 31, 2019
    Publication date: August 6, 2020
    Inventors: Raghuveer S. MAKALA, Senaka KANAKAMEDALA, Yao-Sheng LEE, Jian CHEN
  • Patent number: 10622369
    Abstract: A three-dimensional memory device includes semiconductor devices located on a semiconductor substrate, lower interconnect level dielectric layers embedding lower interconnect structures, an alternating stack of insulating layers and electrically conductive layers overlying the lower interconnect level dielectric layers and including stepped surfaces, memory stack structures vertically extending through the alternating stack, and contact via structures extending downward from the stepped surfaces through underlying portions of the alternating stack to the lower interconnect structures. Each of the contact via structures laterally contacts an electrically conductive layer located at the stepped surfaces, and provides electrical interconnection to an underlying semiconductor device. A top portion of each contact via structures contacts an electrically conductive layer, and is electrically isolated from other underlying electrically conductive layers.
    Type: Grant
    Filed: January 22, 2018
    Date of Patent: April 14, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Fei Zhou, Raghuveer S. Makala, Hiroyuki Kinoshita, Yanli Zhang, James Kai, Johann Alsmeier, Stephen Ross, Senaka Kanakamedala
  • Patent number: 10622368
    Abstract: Azimuthally-split metal-semiconductor alloy floating gate electrodes can be formed by providing an alternating stack of insulating layers and spacer material layers, forming a dielectric separator structure extending through the alternating stack, and forming memory openings that divides the dielectric separator structure into a plurality of dielectric separator structures. The spacer material layers are formed as, or are replaced with, electrically conductive layers, which are laterally recessed selective to the insulating layers and the plurality of dielectric separator structures to form a pair of lateral cavities at each level of the electrically conductive layers in each memory opening. After formation of a blocking dielectric layer, a pair of physically disjoined metal-semiconductor alloy portions are formed in each pair of lateral cavities as floating gate electrodes. A tunneling dielectric layer and a semiconductor channel layer is subsequently formed in each memory opening.
    Type: Grant
    Filed: August 3, 2016
    Date of Patent: April 14, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Senaka Kanakamedala, Raghuveer S. Makala, Rahul Sharangpani, Somesh Peri, Yao-Sheng Lee, James Kai
  • Publication number: 20190371803
    Abstract: Azimuthally-split metal-semiconductor alloy floating gate electrodes can be formed by providing an alternating stack of insulating layers and spacer material layers, forming a dielectric separator structure extending through the alternating stack, and forming memory openings that divides the dielectric separator structure into a plurality of dielectric separator structures. The spacer material layers are formed as, or are replaced with, electrically conductive layers, which are laterally recessed selective to the insulating layers and the plurality of dielectric separator structures to form a pair of lateral cavities at each level of the electrically conductive layers in each memory opening. After formation of a blocking dielectric layer, a pair of physically disjoined metal-semiconductor alloy portions are formed in each pair of lateral cavities as floating gate electrodes. A tunneling dielectric layer and a semiconductor channel layer is subsequently formed in each memory opening.
    Type: Application
    Filed: August 3, 2016
    Publication date: December 5, 2019
    Inventors: Senaka Kanakamedala, Raghuveer S. Makala, Rahul Sharangpani, Somesh Peri, Yao-Sheng Lee, James Kai
  • Patent number: 10468596
    Abstract: First stacked rail structures including a first conductive rail, a selector rail, and a sacrificial material rail and separated by first trenches are formed over a substrate. First dielectric isolation structures are formed in the first trenches. Second trenches are formed, which divides the first stacked rail structures above the first conductive rails. Second dielectric isolation structures in the second trenches. Pillar structures are formed, which include a respective vertical stack of a selector element and a sacrificial material pillar. The sacrificial material pillars are replaced with phase change memory material pillars by a damascene method that deposits and planarizes a phase change memory material. Second conductive rails are formed over the phase change memory material pillars. Sidewalls of the phase change memory material pillars are not subjected to etch damage, thereby enhancing electrical characteristics of the phase change memory material pillars.
    Type: Grant
    Filed: February 21, 2018
    Date of Patent: November 5, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Raghuveer S. Makala, Senaka Kanakamedala, Yao-Sheng Lee
  • Publication number: 20190259946
    Abstract: First stacked rail structures including a first conductive rail, a selector rail, and a sacrificial material rail and separated by first trenches are formed over a substrate. First dielectric isolation structures are formed in the first trenches. Second trenches are formed, which divides the first stacked rail structures above the first conductive rails. Second dielectric isolation structures in the second trenches. Pillar structures are formed, which include a respective vertical stack of a selector element and a sacrificial material pillar. The sacrificial material pillars are replaced with phase change memory material pillars by a damascene method that deposits and planarizes a phase change memory material. Second conductive rails are formed over the phase change memory material pillars. Sidewalls of the phase change memory material pillars are not subjected to etch damage, thereby enhancing electrical characteristics of the phase change memory material pillars.
    Type: Application
    Filed: February 21, 2018
    Publication date: August 22, 2019
    Inventors: Raghuveer S. Makala, Senaka Kanakamedala, Yao-Sheng Lee
  • Publication number: 20190229125
    Abstract: A three-dimensional memory device includes semiconductor devices located on a semiconductor substrate, lower interconnect level dielectric layers embedding lower interconnect structures, an alternating stack of insulating layers and electrically conductive layers overlying the lower interconnect level dielectric layers and including stepped surfaces, memory stack structures vertically extending through the alternating stack, and contact via structures extending downward from the stepped surfaces through underlying portions of the alternating stack to the lower interconnect structures. Each of the contact via structures laterally contacts an electrically conductive layer located at the stepped surfaces, and provides electrical interconnection to an underlying semiconductor device. A top portion of each contact via structures contacts an electrically conductive layer, and is electrically isolated from other underlying electrically conductive layers.
    Type: Application
    Filed: January 22, 2018
    Publication date: July 25, 2019
    Inventors: Fei Zhou, Raghuveer S. Makala, Hiroyuki Kinoshita, Yanli Zhang, James Kai, Johann Alsmeier, Stephen Ross, Senaka Kanakamedala
  • Patent number: 10256247
    Abstract: A vertically alternating sequence of silicon-containing semiconductor layers and sacrificial material layers is formed over a substrate. Memory stack structures are formed through the vertically alternating sequence. After formation of backside trenches, backside recesses are formed by removing the sacrificial material layers employing an isotropic etchant introduced through the backside trenches. Composite electrically conductive layers are formed by reacting a metal layer with surface portions of silicon-containing semiconductor layers. A dielectric material can be anisotropically deposited to form a continuous material portion that includes vertically-extending dielectric material portions formed in the backside trenches and cavity-containing layers formed in the backside recesses. The composite electrically conductive layers include word lines, which are vertically spaced by cavity-containing layers.
    Type: Grant
    Filed: February 8, 2018
    Date of Patent: April 9, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Senaka Kanakamedala, Raghuveer S. Makala, Yao-Sheng Lee
  • Publication number: 20180331117
    Abstract: A joint level dielectric material layer is formed over a first alternating stack of first insulating layers and first spacer material layers. A first memory opening is formed with a tapered sidewall of the joint level dielectric material layer. A second alternating stack of second insulating layers and second spacer material layers is formed over the joint level dielectric material layer. An inter-tier memory opening is formed, which includes a volume of an second memory opening that extends through the second alternating stack and a volume of the first memory opening. A memory film and a semiconductor channel are formed in the inter-tier memory opening with respective tapered portions overlying the tapered sidewall of the joint level dielectric material layer.
    Type: Application
    Filed: May 12, 2017
    Publication date: November 15, 2018
    Inventors: Monica TITUS, Zhixin CUI, Senaka KANAKAMEDALA, Yao-Sheng LEE, Chih-Yu LEE
  • Patent number: 10050054
    Abstract: A layer stack including an alternating stack of insulating layers and sacrificial material layers is formed over a substrate. After formation of memory stack structures, backside trenches are formed through the layer stack. The sacrificial material layers are replaced with electrically conductive layers. Drain select level dielectric isolation structures are formed through drain select level of the stack after formation of the electrically conductive layers. The drain select level dielectric isolation structures laterally separate portions of conductive layers that are employed as drain select level gate electrodes for the memory stack structures.
    Type: Grant
    Filed: October 5, 2016
    Date of Patent: August 14, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Johann Alsmeier, Raghuveer S. Makala, Senaka Kanakamedala, Rahul Sharangpani, James Kai
  • Patent number: 9984963
    Abstract: A memory stack structure including a memory film and a vertical semiconductor channel can be formed within each memory opening that extends through a stack including an alternating plurality of insulator layers and sacrificial material layers. After formation of backside recesses through removal of the sacrificial material layers selective to the insulator layers, a backside blocking dielectric layer is formed in the backside recesses and sidewalls of the memory stack structures. A metallic barrier material portion can be formed in each backside recess. A cobalt metal portion can be formed in each backside recess. Each backside recess can be filled with a portion of a backside blocking dielectric layer, a metallic barrier material portion, a cobalt metal portion, and a metallic material portion including a material other than cobalt.
    Type: Grant
    Filed: July 29, 2016
    Date of Patent: May 29, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Somesh Peri, Rahul Sharangpani, Raghuveer S. Makala, Senaka Kanakamedala, Keerti Shukla
  • Publication number: 20180097009
    Abstract: A layer stack including an alternating stack of insulating layers and sacrificial material layers is formed over a substrate. After formation of memory stack structures, backside trenches are formed through the layer stack. The sacrificial material layers are replaced with electrically conductive layers. Drain select level dielectric isolation structures are formed through drain select level of the stack after formation of the electrically conductive layers. The drain select level dielectric isolation structures laterally separate portions of conductive layers that are employed as drain select level gate electrodes for the memory stack structures.
    Type: Application
    Filed: October 5, 2016
    Publication date: April 5, 2018
    Inventors: Yanli ZHANG, Johann ALSMEIER, Raghuveer S. MAKALA, Senaka KANAKAMEDALA, Rahul SHARANGPANI, James KAI