Patents by Inventor Yao-Sheng Lee

Yao-Sheng Lee 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: 10950629
    Abstract: A three-dimensional memory device includes alternating stacks of insulating strips and electrically conductive strips laterally spaced apart by line trenches, and an alternating two-dimensional array of memory stack assemblies and dielectric pillar structures located in the line trenches. Each of the line trenches is filled with a respective laterally alternating sequence of memory stack assemblies and dielectric pillar structures. Each memory stack assembly includes a vertical semiconductor channel and a pair of memory film. The vertical semiconductor channel includes a semiconductor channel layer having large grains, which can be provided by a selective semiconductor growth from seed semiconductor material layers, sacrificial semiconductor material layers, or a single crystalline semiconductor material in a semiconductor substrate underlying the alternating stacks.
    Type: Grant
    Filed: May 19, 2020
    Date of Patent: March 16, 2021
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Raghuveer S. Makala, Fei Zhou, Senaka Krishna Kanakamedala, Yao-Sheng Lee
  • 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: 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
  • Publication number: 20200279868
    Abstract: A three-dimensional memory device includes alternating stacks of insulating strips and electrically conductive strips laterally spaced apart by line trenches, and an alternating two-dimensional array of memory stack assemblies and dielectric pillar structures located in the line trenches. Each of the line trenches is filled with a respective laterally alternating sequence of memory stack assemblies and dielectric pillar structures. Each memory stack assembly includes a vertical semiconductor channel and a pair of memory film. The vertical semiconductor channel includes a semiconductor channel layer having large grains, which can be provided by a selective semiconductor growth from seed semiconductor material layers, sacrificial semiconductor material layers, or a single crystalline semiconductor material in a semiconductor substrate underlying the alternating stacks.
    Type: Application
    Filed: May 19, 2020
    Publication date: September 3, 2020
    Inventors: Raghuveer S. Makala, Fei Zhou, Senaka Krishna Kanakamedala, Yao-Sheng Lee
  • Patent number: 10741572
    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 insulating layers and sacrificial material layers. After formation of backside recesses through removal of the sacrificial material layers selective to the insulating layers, a backside blocking dielectric layer may be 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 metallic material portion is formed on the metallic barrier material portion. Subsequently, a metal portion comprising a material selected from cobalt and ruthenium is formed directly on a sidewall of the metallic barrier material portion and a sidewall of the metallic material portion and an overlying insulating surface and an underlying insulating surface.
    Type: Grant
    Filed: June 15, 2017
    Date of Patent: August 11, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Rahul Sharangpani, Raghuveer Makala, Yanli Zhang, Yao-Sheng Lee
  • 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: 10700086
    Abstract: A three-dimensional memory device includes alternating stacks of insulating strips and electrically conductive strips laterally spaced apart by line trenches, and an alternating two-dimensional array of memory stack assemblies and dielectric pillar structures located in the line trenches. Each of the line trenches is filled with a respective laterally alternating sequence of memory stack assemblies and dielectric pillar structures. Each memory stack assembly includes a vertical semiconductor channel and a pair of memory film. The vertical semiconductor channel includes a semiconductor channel layer having large grains, which can be provided by a selective semiconductor growth from seed semiconductor material layers, sacrificial semiconductor material layers, or a single crystalline semiconductor material in a semiconductor substrate underlying the alternating stacks.
    Type: Grant
    Filed: June 28, 2018
    Date of Patent: June 30, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Raghuveer S. Makala, Fei Zhou, Senaka Krishna Kanakamedala, Yao-Sheng Lee
  • 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: 20200006376
    Abstract: A three-dimensional memory device includes alternating stacks of insulating strips and electrically conductive strips laterally spaced apart by line trenches, and an alternating two-dimensional array of memory stack assemblies and dielectric pillar structures located in the line trenches. Each of the line trenches is filled with a respective laterally alternating sequence of memory stack assemblies and dielectric pillar structures. Each memory stack assembly includes a vertical semiconductor channel and a pair of memory film. The vertical semiconductor channel includes a semiconductor channel layer having large grains, which can be provided by a selective semiconductor growth from seed semiconductor material layers, sacrificial semiconductor material layers, or a single crystalline semiconductor material in a semiconductor substrate underlying the alternating stacks.
    Type: Application
    Filed: June 28, 2018
    Publication date: January 2, 2020
    Inventors: Raghuveer S. Makala, Fei Zhou, Senaka Krishna Kanakamedala, Yao-Sheng Lee
  • 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: 10475879
    Abstract: Multiple tier structures including a respective alternating stack of insulating layers and electrically conductive layers is formed over a substrate. A memory opening fill structure extends through the alternating stacks, and includes a vertical semiconductor channel and a memory film. A support pillar structure extends through at least an upper alternating stack, and includes a dummy memory film and a dummy memory film. The support pillar structure may be narrower than the memory opening fill structure at a bottommost layer of the upper alternating stack. Additionally or alternatively, the dummy memory film may be located above a horizontal plane including a topmost surface of a lower alternating stack. Optionally, another support pillar structure including a dielectric material may be provided underneath the support pillar structure in the lower alternating stack.
    Type: Grant
    Filed: June 28, 2018
    Date of Patent: November 12, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Jayavel Pachamuthu, Hiroyuki Kinoshita, Yao-Sheng Lee
  • 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
  • Patent number: 10461163
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate. Memory stack structures are located in a memory array region, each of which includes a memory film and a vertical semiconductor channel. Contact via structures located in the terrace region and contact a respective one of the electrically conductive layers. Each of the electrically conductive layers has a respective first thickness throughout the memory array region and includes a contact portion having a respective second thickness that is greater than the respective first thickness within a terrace region. The greater thickness of the contact portion prevents an etch-through during formation of contact via cavities for forming the contact via structures.
    Type: Grant
    Filed: November 15, 2017
    Date of Patent: October 29, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Senaka Krishna Kanakamedala, Yoshihiro Kanno, Raghuveer S. Makala, Yanli Zhang, Jin Liu, Murshed Chowdhury, Yao-Sheng Lee
  • Patent number: 10438964
    Abstract: A strap level sacrificial layer and an alternating stack of insulating layers and spacer material layers are formed over a substrate. An array of memory stack structures is formed through the alternating stack and the strap level sacrificial layer. Each memory film in the memory stack structures includes a metal oxide blocking dielectric. After formation of a source cavity by removal of the strap level sacrificial layer, an atomic layer etch process can be employed to remove portions of the metal oxide blocking dielectrics at the level of the source cavity. Outer sidewalls of semiconductor channels in the memory stack structures are exposed by additional etch processes, and a source strap layer is selectively deposited in the source cavity in contact with the semiconductor channel. If the spacer material layers are sacrificial material layers, all volumes of the sacrificial material layers can be replaced with the electrically conductive layers.
    Type: Grant
    Filed: June 26, 2017
    Date of Patent: October 8, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Raghuveer S. Makala, Senaka Krishna Kanakamedala, Yanli Zhang, 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
  • Patent number: 10381434
    Abstract: Multiple tier structures including a respective alternating stack of insulating layers and electrically conductive layers is formed over a substrate. A memory opening fill structure extends through the alternating stacks, and includes a vertical semiconductor channel and a memory film. A support pillar structure extends through at least an upper alternating stack, and includes a dummy memory film and a dummy memory film. The support pillar structure may be narrower than the memory opening fill structure at a bottommost layer of the upper alternating stack. Additionally or alternatively, the dummy memory film may be located above a horizontal plane including a topmost surface of a lower alternating stack. Optionally, another support pillar structure including a dielectric material may be provided underneath the support pillar structure in the lower alternating stack.
    Type: Grant
    Filed: June 28, 2018
    Date of Patent: August 13, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Jayavel Pachamuthu, Hiroyuki Kinoshita, Yao-Sheng Lee
  • Publication number: 20190148506
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate. Memory stack structures are located in a memory array region, each of which includes a memory film and a vertical semiconductor channel. Contact via structures located in the terrace region and contact a respective one of the electrically conductive layers. Each of the electrically conductive layers has a respective first thickness throughout the memory array region and includes a contact portion having a respective second thickness that is greater than the respective first thickness within a terrace region. The greater thickness of the contact portion prevents an etch-through during formation of contact via cavities for forming the contact via structures.
    Type: Application
    Filed: November 15, 2017
    Publication date: May 16, 2019
    Inventors: Senaka Krishna KANAKAMEDALA, Yoshihiro KANNO, Raghuveer S. MAKALA, Yanli ZHANG, Jin LIU, Murshed CHOWDHURY, Yao-Sheng LEE
  • Patent number: 10269620
    Abstract: Contacts to peripheral devices extending through multiple tier structures of a three-dimensional memory device can be formed with minimal additional processing steps. First peripheral via cavities through a first tier structure can be formed concurrently with formation of first memory openings. Sacrificial via fill structures can be formed in the first peripheral via cavities concurrently with formation of sacrificial memory opening fill structures that are formed in the first memory openings. Second peripheral via cavities through a second tier structure can be formed concurrently with formation of word line contact via cavities that extend to top surfaces of electrically conductive layers in the first and second tier structures. After removal of the sacrificial via fill structures, the first and second peripheral via cavities can be filled with a conductive material to form peripheral contact via structures concurrently with formation of word line contact via structures.
    Type: Grant
    Filed: September 23, 2016
    Date of Patent: April 23, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Jixin Yu, Zhenyu Lu, Hiroyuki Ogawa, Daxin Mao, Kensuke Yamaguchi, Sung Tae Lee, Yao-sheng Lee, Johann Alsmeier
  • Patent number: 10262945
    Abstract: A three-dimensional memory device includes driver transistors containing boron doped semiconductor active regions, device contact via structures in physical contact with the boron doped semiconductor active regions, the device contact via structures containing at least one of tantalum, tungsten, and cobalt, and a three-dimensional memory array located over the driver transistors and including an alternating stack of insulating layers and electrically conductive layers and memory structures vertically extending through the alternating stack.
    Type: Grant
    Filed: April 28, 2017
    Date of Patent: April 16, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Raghuveer S. Makala, Murshed Chowdhury, Keerti Shukla, Tomohisa Abe, Yao-Sheng Lee, James Kai