Patents by Inventor Raghuveer S. Makala

Raghuveer S. Makala 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: 20220238453
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers, and memory stack structures vertically extending through the alternating stack. Each of the memory stack structures includes a respective vertical semiconductor channel and a respective vertical stack of memory elements located at levels of the electrically conductive layers. Each of the electrically conductive layers includes a respective conductive liner comprising molybdenum carbide or carbonitride, and a respective molybdenum metal fill material portion.
    Type: Application
    Filed: January 22, 2021
    Publication date: July 28, 2022
    Inventors: Rahul SHARANGPANI, Raghuveer S. MAKALA, Fei ZHOU
  • Patent number: 11398451
    Abstract: A semiconductor structure includes a memory die bonded to a support die. The memory die includes an alternating stack of insulating layers and electrically conductive layers located over a first single crystalline semiconductor layer, and memory stack structures extending through the alternating stack and containing respective memory film and a respective vertical semiconductor channel including a single crystalline channel semiconductor material. The support die includes a peripheral circuitry. Substrates employed to provide the memory die and the support die can be reused by replacing one of the substrates with an alternative low-cost substrate that provides structural support to the bonded assembly.
    Type: Grant
    Filed: November 30, 2020
    Date of Patent: July 26, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ashish Baraskar, Raghuveer S. Makala, Peter Rabkin
  • Publication number: 20220231048
    Abstract: A ferroelectric memory device includes an alternating stack of insulating layers and electrically conductive layers, a memory opening vertically extending through the alternating stack, and a memory opening fill structure located in the memory opening and containing a vertical stack of memory elements and a vertical semiconductor channel. Each memory element within the vertical stack of memory elements includes a crystalline ferroelectric memory material portion and an epitaxial template portion.
    Type: Application
    Filed: January 15, 2021
    Publication date: July 21, 2022
    Inventors: Rahul SHARANGPANI, Raghuveer S. MAKALA, Fei ZHOU, Adarsh RAJASHEKHAR
  • Patent number: 11393780
    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: Grant
    Filed: April 17, 2020
    Date of Patent: July 19, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ramy Nashed Bassely Said, Senaka Kanakamedala, Raghuveer S. Makala
  • Publication number: 20220223470
    Abstract: A method of forming a structure includes forming an alternating stack of first material layers and second material layers over a substrate, forming a mask layer over the alternating stack, forming a cavity in the mask layer, forming a first cladding liner on a sidewall of the cavity in the mask layer, and forming a via opening the alternating stack by performing an anisotropic etch process that transfers a pattern of the cavity in the mask layer through the alternating stack using a combination of the first cladding liner and the mask layer as an etch mask.
    Type: Application
    Filed: March 31, 2022
    Publication date: July 14, 2022
    Inventors: Roshan Jayakhar TIRUKKONDA, Monica TITUS, Senaka KANAKAMEDALA, Raghuveer S. MAKALA, Rahul SHARANGPANI, Adarsh RAJASHEKAR
  • Patent number: 11387244
    Abstract: An alternating stack of insulating layers and spacer material layers can be formed over a substrate. The spacer material layers may be formed as, or may be subsequently replaced with, electrically conductive layers. A memory opening can be formed through the alternating stack, and annular lateral recesses are formed at levels of the insulating layers. Metal portions are formed in the annular lateral recesses, and a semiconductor material layer is deposited over the metal portions. Metal-semiconductor alloy portions are formed by performing an anneal process, and are subsequently removed by performing a selective etch process. Remaining portions of the semiconductor material layer include a vertical stack of semiconductor material portions, which may be optionally converted, partly or fully, into silicon nitride material portions. The semiconductor material portions and/or the silicon nitride material portions can be employed as discrete charge storage elements.
    Type: Grant
    Filed: April 15, 2020
    Date of Patent: July 12, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Raghuveer S. Makala, Senaka Kanakamedala, Fei Zhou, Yao-Sheng Lee
  • Patent number: 11387250
    Abstract: A three-dimensional memory device includes a vertically alternating stack of insulating layers and electrically conductive layers located over a top surface of a substrate and memory stack structures extending through the alternating stack. Each of the memory stack structures contains a respective memory film and a respective vertical semiconductor channel, and each of the insulating layers contains a metal-organic framework (MOF) material portion. The MOF material portion has a low dielectric constant, and reduces RC coupling between the electrically conductive layers. An optional airgap may be located within the MOF material portion to further reduce the effective dielectric constant. Optionally, discrete charge storage regions or floating gates may be formed only at the levels of the electrically conductive layers to reduce program disturb and noise in the device.
    Type: Grant
    Filed: December 20, 2019
    Date of Patent: July 12, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ramy Nashed Bassely Said, Senaka Kanakamedala, Fei Zhou, Raghuveer S. Makala, Yao-Sheng Lee
  • Patent number: 11377733
    Abstract: A method of depositing tungsten over a substrate includes disposing the substrate into a vacuum enclosure of a tungsten deposition apparatus, performing a first tungsten deposition process that deposits a first tungsten layer over a physically exposed surface of the substrate by flowing a fluorine-containing tungsten precursor gas into the vacuum enclosure, performing an in-situ oxidation process by exposing the first tungsten layer to an oxidation agent gas while the substrate remains within the vacuum enclosure without breaking vacuum and forming a tungsten oxyfluoride gas which is pumped out of the vacuum enclosure, and performing a second tungsten deposition process that deposits a second tungsten layer on the first tungsten layer by flowing the fluorine-containing tungsten precursor gas into the vacuum enclosure in a second tungsten deposition process after the in-situ oxidation process.
    Type: Grant
    Filed: August 7, 2020
    Date of Patent: July 5, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Fei Zhou, Raghuveer S. Makala, Rahul Sharangpani, Yusuke Mukae, Naoki Takeguchi
  • Publication number: 20220208600
    Abstract: A source-level semiconductor layer and an alternating stack of first material layers and second material layers is formed above a substrate. A hard mask layer is formed over the alternating stack, and is subsequently patterned to provide a pattern of cavities therethrough. Via openings are formed through the alternating stack by performing an anisotropic etch process. A cladding liner is formed on sidewalls of the cavities in the hard mask layer and on a top surface of the hard mask layer. The via openings are vertically extended at least through the source-level semiconductor layer by performing a second anisotropic etch process employing a combination of the cladding liner and the hard mask layer as an etch mask.
    Type: Application
    Filed: October 22, 2021
    Publication date: June 30, 2022
    Inventors: Roshan Jayakhar TIRUKKONDA, Senaka KANAKAMEDALA, Raghuveer S. MAKALA, Rahul SHARANGPANI, Monica TITUS, Adarsh RAJASHEKHAR
  • Publication number: 20220208556
    Abstract: An alternating stack of first material layers and second material layers can be formed over a semiconductor material layer. A patterning film is formed over the alternating stack, and openings are formed through the patterning film. Via openings are formed through the alternating stack at least to a top surface of the semiconductor material layer by performing a first anisotropic etch process that transfers a pattern of the openings in the patterning film. A cladding liner can be formed on a top surface of the patterning film and sidewalls of the openings in the pattering film. The via openings can be vertically extended through the semiconductor material layer at least to a bottom surface of the semiconductor material layer by performing a second anisotropic etch process employing the cladding liner as an etch mask.
    Type: Application
    Filed: June 23, 2021
    Publication date: June 30, 2022
    Inventors: Roshan Jayakhar TIRUKKONDA, Senaka KANAKAMEDALA, Rahul SHARANGPANI, Raghuveer S. MAKALA, Monica TITUS
  • Publication number: 20220208776
    Abstract: A method includes forming an alternating stack of first and second layers, forming a composite hard mask layer over the alternating stack, forming openings in the hard mask, and forming via openings through the alternating stack by performing an anisotropic etch process that transfers a pattern of the openings in the composite hard mask layer through the alternating stack. The compositing hard mask includes a first cladding material layer which has higher etch resistance than upper and lower patterning films of the composite hard mask.
    Type: Application
    Filed: February 1, 2022
    Publication date: June 30, 2022
    Inventors: Monica TITUS, Roshan Jayakhar TIRUKKONDA, Senaka KANAKAMEDALA, Raghuveer S. MAKALA
  • Publication number: 20220208785
    Abstract: An alternating stack of first material layers and second material layers is formed over a substrate. A hard mask layer is formed over the alternating stack. Optionally, an additional hard mask layer can be formed over the hard mask layer. A photoresist layer is applied and patterned, and cavities are formed in the hard mask layer by performing a first anisotropic etch process that transfers a pattern of the openings in the photoresist layer through the hard mask layer. Via openings are formed through an upper portion of the alternating stack by performing a second anisotropic etch process. A cladding liner can be optionally formed on sidewalls of the cavities in the hard mask layer. The via openings can be vertically extend through all layers within the alternating stack by performing a third anisotropic etch process.
    Type: Application
    Filed: December 29, 2020
    Publication date: June 30, 2022
    Inventors: Monica TITUS, Senaka KANAKAMEDALA, Rahul SHARANGPANI, Raghuveer S. MAKALA, Yao-Sheng LEE
  • Patent number: 11374020
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers, and a memory stack structure vertically extending through the alternating stack. The memory stack structure includes a vertical semiconductor channel and a memory film. The vertical semiconductor channel can include a III-V compound semiconductor channel material. A III-V compound substrate semiconductor layer or a III-V compound semiconductor source region can be used to provide low-resistance electrical connection to a bottom end of the vertical semiconductor channel, and a drain region including a graded III-V compound semiconductor material can be used to provide low-resistance electrical connection to a top end of the vertical semiconductor channel.
    Type: Grant
    Filed: May 29, 2020
    Date of Patent: June 28, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ashish Baraskar, Peter Rabkin, Raghuveer S. Makala
  • Publication number: 20220189993
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers and memory stack structures vertically extending through the alternating stack. Each of the memory stack structures includes a vertical semiconductor channel and a vertical stack of ferroelectric memory elements surrounding the vertical semiconductor channel and located at levels of the electrically conductive layers. Each of the ferroelectric memory elements includes a respective vertical stack of a first ferroelectric material portion and a second ferroelectric material portion that differs from the first ferroelectric material portion by at least one of a material composition and a lateral thickness.
    Type: Application
    Filed: December 15, 2020
    Publication date: June 16, 2022
    Inventors: Roshan TIRUKKONDA, Ramy Nashed Bassely SAID, Senaka KANAKAMEDALA, Rahul SHARANGPANI, Raghuveer S. MAKALA, Adarsh RAJASHEKHAR, Fei ZHOU
  • Publication number: 20220165937
    Abstract: A method of forming a magnetoresistive random access memory (MRAM) device includes providing a first die containing a selector material layer located over a first substrate, providing a second die containing a MRAM layer stack located over a second substrate, and bonding the first die to the second die.
    Type: Application
    Filed: February 14, 2022
    Publication date: May 26, 2022
    Inventors: Jeffrey LILLE, Joyeeta NAG, Raghuveer S. MAKALA
  • Publication number: 20220157852
    Abstract: A ferroelectric transistor includes a semiconductor channel comprising a semiconductor material, a strained and/or defect containing ferroelectric gate dielectric layer located on a surface of the semiconductor channel, a source region located on a first end portion of the semiconductor channel, and a drain region located on a second end portion of the semiconductor channel.
    Type: Application
    Filed: November 13, 2020
    Publication date: May 19, 2022
    Inventors: Bhagwati PRASAD, Joyeeta NAG, Seung-Yeul YANG, Adarsh RAJASHEKHAR, Raghuveer S. MAKALA
  • Publication number: 20220157966
    Abstract: A ferroelectric transistor includes a semiconductor channel comprising a semiconductor material, a strained and/or defect containing ferroelectric gate dielectric layer located on a surface of the semiconductor channel, a source region located on a first end portion of the semiconductor channel, and a drain region located on a second end portion of the semiconductor channel.
    Type: Application
    Filed: November 13, 2020
    Publication date: May 19, 2022
    Inventors: Bhagwati PRASAD, Joyeeta NAG, Seung-Yeul YANG, Adarsh RAJASHEKHAR, Raghuveer S. MAKALA
  • Publication number: 20220139960
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers, a memory opening vertically extending through the alternating stack, and a memory opening fill structure located in the memory opening and including a vertical stack of charge storage elements, a vertical semiconductor channel, a ferroelectric material layer located between the vertical stack of charge storage elements and the vertical semiconductor channel, and a blocking dielectric layer located between the ferroelectric material layer and the vertical semiconductor channel. A tunneling dielectric layer is located between at least one of the electrically conductive layers and the vertical stack of charge storage elements.
    Type: Application
    Filed: January 19, 2022
    Publication date: May 5, 2022
    Inventors: Ramy Nashed Bassely SAID, Adarsh RAJASHEKHAR, Senaka KANAKAMEDALA, Raghuveer S. MAKALA
  • Publication number: 20220139949
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate. Each electrically conductive layer within a subset of the electrically conductive layers includes a respective first metal layer containing an elemental metal and a respective first metal silicide layer containing a metal silicide of the elemental metal. Memory openings vertically extend through the alternating stack. Memory opening fill structures located within the memory openings can include a respective memory film and a respective vertical semiconductor channel.
    Type: Application
    Filed: October 30, 2020
    Publication date: May 5, 2022
    Inventors: Rahul SHARANGPANI, Raghuveer S. MAKALA, Fei ZHOU, Adarsh RAJASHEKHAR
  • Patent number: 11322509
    Abstract: A memory device includes a silicon-germanium source contact layer, an alternating stack of insulating layers and electrically conductive layers located over the silicon-germanium source contact layer, and a memory stack structure vertically extending through the alternating stack. The memory stack structure comprises a memory film and a vertical semiconductor channel that contacts the memory film. The silicon-germanium source contact layer contacts a cylindrical portion of an outer sidewall of the vertical semiconductor channel. Logic circuits for operating the memory elements may be provided on a substrate within a same semiconductor die, or may be provided in another semiconductor die that is bonded to the semiconductor die containing the memory device.
    Type: Grant
    Filed: August 24, 2020
    Date of Patent: May 3, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ashish Baraskar, Raghuveer S. Makala, Peter Rabkin