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: 9672916
    Abstract: Methods for performing memory operations on a memory array that includes inverted NAND strings are described. The memory operations may include erase operations, read operations, programming operations, program verify operations, and erase verify operations. An inverted NAND string may include a string of inverted floating gate transistors or a string of inverted charge trap transistors. In one embodiment, an inverted floating gate transistor may include a tunneling layer between a floating gate of the inverted floating gate transistor and a control gate of the inverted floating gate transistor. The arrangement of the tunneling layer between the floating gate and the control gate allows electrons to be added to or removed from the floating gate via F-N tunneling between the floating gate and the control gate. The inverted NAND string may be formed above a substrate and oriented such that the inverted NAND string is orthogonal to the substrate.
    Type: Grant
    Filed: March 28, 2016
    Date of Patent: June 6, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, George Samachisa, Johann Alsmeier, Jian Chen
  • Patent number: 9673213
    Abstract: A method of manufacturing a structure includes forming an in-process alternating stack including insulating layers and spacer material layers over a substrate, forming two sets of stepped surfaces by dividing the in-process alternating stack into a first alternating stack and a second alternating stack, the first alternating stack having first stepped surfaces and the second alternating stack having second stepped surfaces, forming at least one memory stack structure through the first alternating stack, each of the at least one memory stack structure including charge storage regions, a tunneling dielectric, and a semiconductor channel, replacing portions of the insulating layers in the first alternating stack with electrically conductive layers while leaving intact portions of the insulating layers in the second alternating stack, and forming a contact via structure through the second alternating stack to contact a peripheral semiconductor device under the second stack.
    Type: Grant
    Filed: February 15, 2016
    Date of Patent: June 6, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Jixin Yu, Yanli Zhang, Zhenyu Lu, Johann Alsmeier, Daxin Mao
  • Patent number: 9672917
    Abstract: Systems and methods for implementing and using stacked vertical memory array architectures. A first NAND string may be formed or arranged above a second NAND string. The first NAND string may include a first drain-side select gate connected to a first set of memory cell transistors connected to a first source-side select gate. The second NAND string may include a second drain-side select gate connected to a second set of memory cell transistors connected to a second source-side select gate. The first NAND string and the second NAND string may comprise portions of the same or different memory array architectures (e.g., the first NAND string may be part of a memory array that uses U-shaped NAND strings and the second NAND string may be part of a memory array that uses single vertical NAND strings).
    Type: Grant
    Filed: May 26, 2016
    Date of Patent: June 6, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Xiying Costa, Henry Chien, Yao-Sheng Lee, Yanli Zhang
  • Publication number: 20170148810
    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. An alternating sequence of support pedestal structures and conductive rail structures extending along a same horizontal direction are provided between the substrate and the alternating stack. Each memory stack structure straddles a vertical interface between a conductive rail structure and a support pedestal structure. A semiconductor channel in each memory stack structure contacts a respective conductive rail structure, and is electrically isolated from an adjacent support pedestal structure by a portion of a memory film. The conductive rail structures can function as source regions of memory device.
    Type: Application
    Filed: August 1, 2016
    Publication date: May 25, 2017
    Inventors: James Kai, Johann Alsmeier, Jin Liu, Yanli Zhang
  • Publication number: 20170148800
    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, each memory stack structure extending through the alternating stack and including a memory film and a semiconductor channel laterally surrounded by the memory film, and an array of dielectric pillars located between the alternating stack and the substrate.
    Type: Application
    Filed: February 8, 2016
    Publication date: May 25, 2017
    Inventors: Masatoshi NISHIKAWA, Jin LIU, Chun GE, Yanli ZHANG
  • Publication number: 20170148811
    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: Application
    Filed: November 17, 2016
    Publication date: May 25, 2017
    Inventors: Tong ZHANG, Johann ALSMEIER, James KAI, Jin LIU, Yanli ZHANG
  • Patent number: 9646990
    Abstract: Methods of making monolithic three-dimensional memory devices include performing a first etch to form a memory opening and a second etch using a different etching process to remove a damaged portion of the semiconductor substrate from the bottom of the memory opening. A single crystal semiconductor material is formed over the substrate in the memory opening using an epitaxial growth process. Additional embodiments include improving the quality of the interface between the semiconductor channel material and the underlying semiconductor layers in the memory opening which may be damaged by the bottom opening etch, including forming single crystal semiconductor channel material by epitaxial growth from the bottom surface of the memory opening and/or oxidizing surfaces exposed to the bottom opening etch and removing the oxidized surfaces prior to forming the channel material. Monolithic three-dimensional memory devices formed by the embodiment methods are also disclosed.
    Type: Grant
    Filed: June 10, 2016
    Date of Patent: May 9, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Sateesh Koka, Raghuveer S. Makala, Yanli Zhang, Senaka Kanakamedala, Rahul Sharangpani, Yao-Sheng Lee, George Matamis
  • Patent number: 9627399
    Abstract: An alternating stack of insulating layers and sacrificial material layers is formed on a substrate. Separator insulator structures can be optionally formed through the alternating stack. Memory opening are formed through the alternating stack, and the sacrificial material layers are removed selective to the insulating layers. Electrically conductive layers are formed in the lateral recesses by deposition of at least one conductive material. Metal-semiconductor alloy regions are appended to the electrically conductive layers by depositing at least a semiconductor material and inducing reaction of the semiconductor material with the material of the electrically conductive layers and/or a sacrificial metal layer. Memory stack structures can be formed in the memory openings and directly on the metal-semiconductor alloy regions of the electrically conductive layers.
    Type: Grant
    Filed: July 24, 2015
    Date of Patent: April 18, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Senaka Kanakamedala, Raghuveer S. Makala, Yanli Zhang, Yao-Sheng Lee, George Matamis
  • Patent number: 9627395
    Abstract: A stack including an alternating plurality of first material layers and second material layers is provided. A memory opening is formed and at least a contiguous semiconductor material portion including a semiconductor channel is formed therein. The contiguous semiconductor material portion includes an amorphous or polycrystalline semiconductor material. A metallic material portion is provided at a bottom surface of the semiconductor channel, at a top surface of the semiconductor channel, or on portions of an outer sidewall surface of the semiconductor channel. An anneal is performed to induce diffusion of a metal from the metallic material portion through the semiconductor channel, thereby inducing conversion of the amorphous or polycrystalline semiconductor material into a crystalline semiconductor material. The crystalline semiconductor material has a relatively large grain size due to the catalytic crystallization process, and can provide enhanced charge carrier mobility.
    Type: Grant
    Filed: February 11, 2015
    Date of Patent: April 18, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Raghuveer S. Makala, Johann Alsmeier
  • Patent number: 9620514
    Abstract: A memory device includes a plurality of memory cells arranged in a string substantially perpendicular to the major surface of the substrate in a plurality of device levels, at least one first select gate electrode located between the major surface of the substrate and the plurality of memory cells, at least one second select gate electrode located above the plurality of memory cells, a semiconductor channel having a portion that extends vertically along a direction perpendicular to the major surface, a first memory film contacting a first side of the semiconductor channel, and a second memory film contacting a second side of the semiconductor channel. The second memory film is electrically isolated from the first memory film, and is located at a same level as the first memory film.
    Type: Grant
    Filed: June 24, 2015
    Date of Patent: April 11, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: James K. Kai, Yanli Zhang, Henry Chien, Johann Alsmeier
  • Publication number: 20170098655
    Abstract: A memory stack structure includes a cavity including a back gate electrode, a back gate dielectric, a semiconductor channel, and at least one charge storage element. In one embodiment, a line trench can be filled with a memory film layer, and a plurality of semiconductor channels can straddle the line trench. The back gate electrode can extend along the lengthwise direction of the line trench. In another embodiment, an isolated memory opening overlying a patterned conductive layer can be filled with a memory film, and the back gate electrode can be formed within a semiconductor channel and on the patterned conductive layer. A dielectric cap portion electrically isolates the back gate electrode from a drain region. The back gate electrode can be employed to bias the semiconductor channel, and to enable sensing of multinary bits corresponding to different amounts of electrical charges stored in a memory cell.
    Type: Application
    Filed: December 15, 2016
    Publication date: April 6, 2017
    Inventors: Xiying COSTA, Dana LEE, Yanli ZHANG, Johann ALSMEIER, Yingda DONG, Akira MATSUDAIRA
  • Publication number: 20170084623
    Abstract: Metal floating gate electrodes can be formed for a three-dimensional memory device by forming a memory opening having lateral recesses at levels of spacer material layers between insulating layers, depositing a continuous metal layer, and inducing diffusion and agglomeration of the metal into the lateral recesses to form discrete metal portions employing an anneal process. The metallic material can migrate and form the discrete metal portions due to surface tension, which operates to minimize the surface area of the metallic material. Optionally, two or more continuous metal layers can be employed to form discrete metal portions including at least two metals. Optionally, a selective metal deposition process can be performed to deposit additional metal portions including a different metallic material on the discrete metal portions. The metal floating gate electrodes can be formed without employing an etch process. A tunneling dielectric layer and a semiconductor channel can be subsequently formed.
    Type: Application
    Filed: February 29, 2016
    Publication date: March 23, 2017
    Inventors: Rahul SHARANGPANI, Somesh PERI, Raghuveer S. MAKALA, Yanli ZHANG
  • Patent number: 9576975
    Abstract: A vertically repeating stack of a unit layer stack is formed over a substrate. The unit layer stack includes a sacrificial material layer, a lower silicon oxide material layer, a first silicon oxide material layer, and an upper silicon oxide material layer. A memory opening can be formed through the vertically repeating stack, and a layer stack including a blocking dielectric layer, a memory material layer, a tunneling dielectric, and a semiconductor channel can be formed in the memory opening. The sacrificial material layers are replaced with electrically conductive layers. The first silicon oxide material layer can be removed to form backside recesses. Optionally, portions of the memory material layer can be removed to from discrete charge storage regions. The backside recesses can be filled with a low-k dielectric material and/or can include cavities within a dielectric material to provide reduced coupling between electrically conductive layers.
    Type: Grant
    Filed: December 3, 2015
    Date of Patent: February 21, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, James Kai, Raghuveer S. Makala, Jin Liu, Murshed Chowdhury, Camilla Huang, Johann Alsmeier
  • Patent number: 9576971
    Abstract: A memory stack structure includes a cavity including a back gate electrode, a back gate dielectric, a semiconductor channel, and at least one charge storage element. In one embodiment, a line trench can be filled with a memory film layer, and a plurality of semiconductor channels can straddle the line trench. The back gate electrode can extend along the lengthwise direction of the line trench. In another embodiment, an isolated memory opening overlying a patterned conductive layer can be filled with a memory film, and the back gate electrode can be formed within a semiconductor channel and on the patterned conductive layer. A dielectric cap portion electrically isolates the back gate electrode from a drain region. The back gate electrode can be employed to bias the semiconductor channel, and to enable sensing of multinary bits corresponding to different amounts of electrical charges stored in a memory cell.
    Type: Grant
    Filed: December 9, 2014
    Date of Patent: February 21, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Johann Alsmeier, Yingda Dong, Akira Matsudaira
  • Patent number: 9570463
    Abstract: A three-dimensional memory device including multiple stack structures can be formed with a joint region electrode, which is an electrode formed at a joint region located near the interface between an upper stack structure and a lower stack structure. A memory stack structure is formed through the multiple stack structures. The joint region electrode laterally surrounds a portion of the memory stack structure in proximity to the interface between different stack structures. The joint region electrode includes a layer portion having a thickness and a collar portion that laterally surrounds the memory stack structure and having a greater vertical extent than the thickness of the layer portion. The increased vertical extent of the collar portion with respect to the vertical extent of the layer portion provides enhanced control of a portion of a semiconductor channel in the memory stack structure located near the interface between different stack structures.
    Type: Grant
    Filed: October 15, 2015
    Date of Patent: February 14, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Raghuveer S. Makala, Jin Liu, Murshed Chowdhury, Yao-Sheng Lee, Johann Alsmeier
  • Publication number: 20170025431
    Abstract: An alternating stack of insulating layers and sacrificial material layers is formed on a substrate. Separator insulator structures can be optionally formed through the alternating stack. Memory opening are formed through the alternating stack, and the sacrificial material layers are removed selective to the insulating layers. Electrically conductive layers are formed in the lateral recesses by deposition of at least one conductive material. Metal-semiconductor alloy regions are appended to the electrically conductive layers by depositing at least a semiconductor material and inducing reaction of the semiconductor material with the material of the electrically conductive layers and/or a sacrificial metal layer. Memory stack structures can be formed in the memory openings and directly on the metal-semiconductor alloy regions of the electrically conductive layers.
    Type: Application
    Filed: July 24, 2015
    Publication date: January 26, 2017
    Inventors: Senaka KANAKAMEDALA, Raghuveer S. MAKALA, Yanli ZHANG, Yao-Sheng LEE, George MATAMIS
  • Patent number: 9553146
    Abstract: A monolithic three dimensional NAND string includes a semiconductor channel, where at least one end portion of the semiconductor channel extending substantially perpendicular to a major surface of a substrate, a plurality of control gate electrodes extending substantially parallel to the major surface of the substrate, an interlevel insulating layer located between adjacent control gate electrodes, a blocking dielectric layer located in contact with the plurality of control gate electrodes and an interlevel insulating layer, a charge storage layer located at least partially in contact with the blocking dielectric layer, and a tunnel dielectric located between the charge storage layer and the semiconductor channel. The charge storage layer has a curved profile.
    Type: Grant
    Filed: June 5, 2014
    Date of Patent: January 24, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Matthias Baenninger, Akira Matsudaira, Yao-Sheng Lee, Johann Alsmeier
  • Patent number: 9538624
    Abstract: An apparatus may include a backlight for illuminating a liquid crystal display and a control module for controlling the illumination of the backlight. The control module may alternate between turning the backlight on and off at a first frequency and turning the backlight on and off at a second frequency.
    Type: Grant
    Filed: December 29, 2011
    Date of Patent: January 3, 2017
    Assignee: INTEL CORPORATION
    Inventors: Yanli Zhang, Akihiro Takagi, Achintya K. Bhowmik, Anil V. Nanduri
  • Patent number: 9530791
    Abstract: A three-dimensional memory device including multiple stack structures can be formed with a joint region electrode, which is an electrode formed at a joint region located near the interface between an upper stack structure and a lower stack structure. A memory stack structure is formed through the multiple stack structures. The joint region electrode laterally surrounds a portion of the memory stack structure in proximity to the interface between different stack structures. The joint region electrode includes a layer portion having a thickness and a collar portion that laterally surrounds the memory stack structure and having a greater vertical extent than the thickness of the layer portion. The increased vertical extent of the collar portion with respect to the vertical extent of the layer portion provides enhanced control of a portion of a semiconductor channel in the memory stack structure located near the interface between different stack structures.
    Type: Grant
    Filed: October 15, 2015
    Date of Patent: December 27, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Raghuveer S. Makala, Jin Liu, Murshed Chowdhury, Yao-Sheng Lee, Johann Alsmeier
  • Publication number: 20160372482
    Abstract: A NAND memory cell region of a NAND device includes a conductive source line that extends substantially parallel to a major surface of a substrate, a first semiconductor channel that extends substantially perpendicular to a major surface of the substrate, and a second semiconductor channel that extends substantially perpendicular to the major surface of the substrate. At least one of a bottom portion and a side portion of the first semiconductor channel contacts the conductive source line and at least one of a bottom portion and a side portion of the second semiconductor channel contacts the conductive source line.
    Type: Application
    Filed: September 2, 2016
    Publication date: December 22, 2016
    Inventors: Yanli Zhang, Go Shoji, Johann Alsmeier, Jayavel Pachamuthu, Yingda Dong, Jiahui Yuan