Patents by Inventor Yanli Zhang

Yanli Zhang 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: 10083982
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, the alternating stack having a memory array region and a contact region containing stepped surfaces, and memory stack structures having a semiconductor channel and a memory film extending through the memory array region of the alternating stack. The electrically conductive layers include a drain select gate electrode and word lines, where the drain select gate electrode is thicker than each of the word lines.
    Type: Grant
    Filed: April 25, 2017
    Date of Patent: September 25, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Keisuke Shigemura, Junichi Ariyoshi, Masanori Tsutsumi, Michiaki Sano, Yanli Zhang, Raghuveer S. Makala
  • Patent number: 10074666
    Abstract: After formation of an alternating stack of insulating layers and sacrificial material layers, a memory opening can be formed through the alternating stack, which is subsequently filled with a columnar semiconductor pedestal portion and a memory stack structure. Breakage of the columnar semiconductor pedestal portion under mechanical stress can be avoided by growing a laterally protruding semiconductor portion by selective deposition of a semiconductor material after removal of the sacrificial material layers to form backside recesses. At least an outer portion of the laterally protruding semiconductor portion can be oxidized to form a tubular semiconductor oxide spacer. Electrically conductive layers can be formed in the backside recesses to provide word lines for a three-dimensional memory device.
    Type: Grant
    Filed: January 9, 2017
    Date of Patent: September 11, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Chun Ge, Yanli Zhang, Johann Alsmeier, Fabo Yu, Jixin Yu
  • Publication number: 20180248013
    Abstract: A trench having a uniform depth is provided in an upper portion of a semiconductor substrate. A continuous dielectric material layer is formed, which includes a gate dielectric that fills an entire volume of the trench. A gate electrode is formed over the gate dielectric such that the gate electrode overlies a center portion of the gate dielectric and does not overlie a first peripheral portion and a second peripheral portion of the gate dielectric that are located on opposing sides of the center portion of the gate dielectric. After formation of a dielectric gate spacer, a source extension region and a drain extension region are formed within the semiconductor substrate by doping respective portions of the semiconductor substrate.
    Type: Application
    Filed: February 28, 2017
    Publication date: August 30, 2018
    Inventors: Murshed CHOWDHURY, Andrew LIN, James KAI, Yanli ZHANG, Johann ALSMEIER
  • Publication number: 20180233513
    Abstract: A memory device includes an alternating stack of insulating layers and electrically conductive layers. Vertical NAND strings are formed through the alternating stack, each of which includes a drain region, memory cell charge storage transistors, and a pair of drain select transistors in a series connection. A common bit line is electrically connected to drain regions of two vertical NAND strings. The drain select transistors of the two vertical NAND strings are configured such that drain select transistors sharing a first common drain select gate electrode provide a higher threshold voltage for one of the two vertical NAND strings, and drain select transistors sharing a second common drain select gate electrode provide a higher threshold voltage for the other of the two vertical NAND strings. The different threshold voltages can be provided by a combination of a masked ion implantation and selective charge injection.
    Type: Application
    Filed: April 9, 2018
    Publication date: August 16, 2018
    Inventors: Yanli Zhang, James Kai, Johann Alsmeier
  • 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
  • Publication number: 20180197876
    Abstract: After formation of an alternating stack of insulating layers and sacrificial material layers, a memory opening can be formed through the alternating stack, which is subsequently filled with a columnar semiconductor pedestal portion and a memory stack structure. Breakage of the columnar semiconductor pedestal portion under mechanical stress can be avoided by growing a laterally protruding semiconductor portion by selective deposition of a semiconductor material after removal of the sacrificial material layers to form backside recesses. At least an outer portion of the laterally protruding semiconductor portion can be oxidized to form a tubular semiconductor oxide spacer. Electrically conductive layers can be formed in the backside recesses to provide word lines for a three-dimensional memory device.
    Type: Application
    Filed: January 9, 2017
    Publication date: July 12, 2018
    Inventors: Chun GE, Yanli ZHANG, Johann ALSMEIER, Fabo YU, Jixin YU
  • Patent number: 10020314
    Abstract: Disclosed herein are methods of forming non-volatile storage. An opening may be etched through a stack of two alternating materials to a semiconductor substrate. A silicon nitride film may be formed on a vertical sidewall of the opening. The semiconductor substrate may be cleaned to remove oxide from the semiconductor substrate. The silicon nitride film protects the materials in the stack while cleaning the semiconductor substrate. The silicon nitride film may be converted to an oxide after cleaning the semiconductor substrate. A semiconductor region may be formed in contact with the cleaned semiconductor substrate. A memory cell film may be formed over the oxide in the opening. Control gates may be formed by replacing one of the materials in the stack with a conductive material. The oxide may serve as a blocking layer between the control gates and charge storage regions in the memory cell film.
    Type: Grant
    Filed: March 2, 2017
    Date of Patent: July 10, 2018
    Assignee: SanDisk Technologies LLC
    Inventors: Ashish Baraskar, Liang Pang, Yanli Zhang, Ching-Huang Lu, Yingda Dong
  • Patent number: 10008570
    Abstract: The contact area between a source strap structure of a buried source layer and semiconductor channels within memory structures can be increased by laterally expanding a source-level volume in which the memory stack structures are formed. In one embodiment, sacrificial semiconductor pedestals can be formed in source-level memory openings prior to formation of a vertically alternating stack of insulating layers and sacrificial material layers. Memory openings can include bulging portions formed by removal of the sacrificial semiconductor pedestals. Memory stack structures can be formed with a greater sidewall surface area in the bulging portions to provide a greater contact area with the source strap structure. Alternatively, bottom portions of memory openings can be expanded selective to upper portions during, or after, formation of the memory openings to provide bulging portions and to increase the contact area with the source strap structure.
    Type: Grant
    Filed: March 14, 2017
    Date of Patent: June 26, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Jixin Yu, Kento Kitamura, Tong Zhang, Chun Ge, Yanli Zhang, Satoshi Shimizu, Yasuo Kasagi, Hiroyuki Ogawa, Daxin Mao, Kensuke Yamaguchi, Johann Alsmeier, James Kai
  • Publication number: 20180138193
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate and memory stack structures extending through the alternating stack. Each memory stack structure includes a memory film and a vertical semiconductor channel. An isolation trench laterally extends along a horizontal direction and divides at least two topmost electrically conductive layers. Two conductive rail structures are located on lengthwise sidewalls of the isolation trench and are electrically shorted to respective segments of the at least two topmost electrically conductive layers.
    Type: Application
    Filed: November 17, 2016
    Publication date: May 17, 2018
    Inventors: Yanli Zhang, Jin Liu, Raghuveer S. Makala, Murshed Chowdhury, Johann Alsmeier
  • Publication number: 20180138194
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, the alternating stack having a memory array region and a contact region containing stepped surfaces, and memory stack structures having a semiconductor channel and a memory film extending through the memory array region of the alternating stack. The electrically conductive layers include a drain select gate electrode and word lines, where the drain select gate electrode is thicker than each of the word lines.
    Type: Application
    Filed: April 25, 2017
    Publication date: May 17, 2018
    Inventors: Keisuke SHIGEMURA, Junichi ARIYOSHI, Masanori TSUTSUMI, Michiaki SANO, Yanli ZHANG, Raghuveer S. MAKALA
  • Patent number: 9972641
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate and memory stack structures extending through the alternating stack. Each memory stack structure includes a memory film and a vertical semiconductor channel. An isolation trench laterally extends along a horizontal direction and divides at least two topmost electrically conductive layers. Two conductive rail structures are located on lengthwise sidewalls of the isolation trench and are electrically shorted to respective segments of the at least two topmost electrically conductive layers.
    Type: Grant
    Filed: November 17, 2016
    Date of Patent: May 15, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Jin Liu, Raghuveer S. Makala, Murshed Chowdhury, Johann Alsmeier
  • Publication number: 20180122906
    Abstract: The contact area between a source strap structure of a buried source layer and semiconductor channels within memory structures can be increased by laterally expanding a source-level volume in which the memory stack structures are formed. In one embodiment, sacrificial semiconductor pedestals can be formed in source-level memory openings prior to formation of a vertically alternating stack of insulating layers and sacrificial material layers. Memory openings can include bulging portions formed by removal of the sacrificial semiconductor pedestals. Memory stack structures can be formed with a greater sidewall surface area in the bulging portions to provide a greater contact area with the source strap structure. Alternatively, bottom portions of memory openings can be expanded selective to upper portions during, or after, formation of the memory openings to provide bulging portions and to increase the contact area with the source strap structure.
    Type: Application
    Filed: March 14, 2017
    Publication date: May 3, 2018
    Inventors: Jixin YU, Kento KITAMURA, Tong ZHANG, Chun GE, Yanli ZHANG, Satoshi SHIMIZU, Yasuo KASAGI, Hiroyuki OGAWA, Daxin MAO, Kensuke YAMAGUCHI, Johann ALSMEIER, James KAI
  • Publication number: 20180122814
    Abstract: A three-dimensional non-volatile memory is provided with reduced programming variation across word lines. The gate lengths of word lines decrease from the top to the bottom of the memory hole. Increased programming speeds due to a narrow memory hole are offset by a smaller gate length at corresponding positions. A blocking dielectric thickness may also be varied, independently or in combination with a variable word line thickness. The blocking dielectric is formed with a horizontal thickness that is larger at regions adjacent to the lower word line layers and smaller at regions adjacent to the upper word line layers. The larger thickness at the lower word line layers reduces the programming speed in the memory hole for the lower word lines relative to the upper word lines. A variance in programming speed resulting from differences in memory hole diameter may be offset by a corresponding variance in blocking dielectric thickness.
    Type: Application
    Filed: December 19, 2017
    Publication date: May 3, 2018
    Applicant: SanDisk Technologies LLC
    Inventors: Ashish Baraskar, Liang Pang, Yanli Zhang, Raghuveer Makala, Yingda Dong
  • Patent number: 9960180
    Abstract: Memory openings can be formed through an alternating stack of insulating layers and sacrificial material layers. Memory stack structures including charge storage elements can be formed in the memory openings. Inter-level charge leakage in a three-dimensional memory device including a charge trapping layer can be minimized by employing a thin continuous charge trapping material layer within each memory opening. After removal of the sacrificial material layers and formation of backside recesses, discrete charge trapping material portions can be formed by selective growth of a charge trapping material from physically exposed surfaces of each thin continuous charge trapping material layer. The discrete charge trapping material portions can function as primary charge storage regions, and inter-level charge leakage can be minimized by the small thickness of the thin continuous charge trapping material layer.
    Type: Grant
    Filed: March 27, 2017
    Date of Patent: May 1, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Fei Zhou, Raghuveer Makala, Rahul Sharangpani, Keerti Shukla, Yanli Zhang, Peng Zhang
  • 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
  • Patent number: 9917100
    Abstract: A three-dimensional memory device includes an alternating stack of electrically conductive layers and insulating layers located over a substrate, an array of memory stack structures. A source conductive line structure is provided between the substrate and the alternating stack. The source conductive line structure includes a plurality of parallel conductive rail structures extending along a same horizontal direction and adjoined to a common conductive straddling structure. Each memory stack structure straddles a vertical interface between a conductive rail structure and a support matrix. A semiconductor channel in each memory stack structure contacts a respective conductive rail structure and the support matrix.
    Type: Grant
    Filed: November 17, 2016
    Date of Patent: March 13, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Tong Zhang, Johann Alsmeier, James Kai, Jin Liu, Yanli Zhang
  • Patent number: 9888224
    Abstract: Systems, devices and methods are described including determining a display type and a display mode, preparing stereoscopic image content in response to the display mode, where preparing the stereoscopic image content includes storing a full resolution left image and a full resolution right image in memory, and determining a display refresh rate in response to at least a content frame rate of the stereoscopic image content. The stereoscopic image content may then be processed for display according to the display type, the display refresh rate, and a power policy.
    Type: Grant
    Filed: July 12, 2016
    Date of Patent: February 6, 2018
    Assignee: Intel Corporation
    Inventor: Yanli Zhang
  • Patent number: 9887207
    Abstract: A monolithic three dimensional NAND string includes a plurality of control gate electrodes extending substantially parallel to a major surface of a substrate, a memory opening extending substantially perpendicular to the major surface of the substrate and filled with a memory opening material including a memory film, and a dummy opening extending substantially perpendicular to the major surface of the substrate and filled with a dummy channel material which is different from the memory opening material. The dummy channel material has a higher Young's modulus than the memory opening material to offset warpage of the substrate due to the one of compressive and tensile stress imposed by the plurality of control gate electrodes on the substrate.
    Type: Grant
    Filed: August 18, 2014
    Date of Patent: February 6, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Raghuveer S. Makala, Johann Alsmeier, Yao-Sheng Lee, Tiger Xu
  • Publication number: 20180033794
    Abstract: A three-dimensional non-volatile memory is provided with reduced programming variation across word lines. The gate lengths of word lines decrease from the top to the bottom of the memory hole. Increased programming speeds due to a narrow memory hole are offset by a smaller gate length at corresponding positions. A blocking dielectric thickness may also be varied, independently or in combination with a variable word line thickness. The blocking dielectric is formed with a horizontal thickness that is larger at regions adjacent to the lower word line layers and smaller at regions adjacent to the upper word line layers. The larger thickness at the lower word line layers reduces the programming speed in the memory hole for the lower word lines relative to the upper word lines. A variance in programming speed resulting from differences in memory hole diameter may be offset by a corresponding variance in blocking dielectric thickness.
    Type: Application
    Filed: July 27, 2016
    Publication date: February 1, 2018
    Applicant: SanDisk Technologies LLC
    Inventors: Ashish Baraskar, Liang Pang, Yanli Zhang, Raghuveer Makala, Yingda Dong
  • Patent number: 9852677
    Abstract: Techniques related to image dithering are described herein. The techniques include receiving an image to be displayed at a display device and entering a content adaptive backlight control mode. The image is dithered during the content adaptive backlight control mode. The dithering is disabled during a panel self-refresh mode.
    Type: Grant
    Filed: November 4, 2014
    Date of Patent: December 26, 2017
    Assignee: Intel Corporation
    Inventors: Yanli Zhang, Seh Kwa