Patents by Inventor Ashish Baraskar

Ashish Baraskar 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: 11721727
    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: August 8, 2023
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ashish Baraskar, Raghuveer S. Makala, Peter Rabkin
  • Patent number: 11538828
    Abstract: A memory device can include a strained single-crystalline silicon layer and an alternating stack of insulating layers and electrically conductive layers located over the strained single-crystalline silicon layer. A memory opening fill structure extending through the alternating stack may include an epitaxial silicon-containing pedestal channel portion, and a vertical semiconductor channel, and a vertical stack of memory elements located adjacent to the vertical semiconductor channel. Additionally or alternatively, a drain region can include a semiconductor drain portion and a nickel-aluminum-semiconductor alloy drain portion.
    Type: Grant
    Filed: August 4, 2020
    Date of Patent: December 27, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ashish Baraskar, Raghuveer S. Makala, Peter Rabkin
  • Patent number: 11508748
    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: November 22, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ashish Baraskar, Peter Rabkin, Raghuveer S. Makala
  • Patent number: 11495613
    Abstract: A memory device can include a strained single-crystalline silicon layer and an alternating stack of insulating layers and electrically conductive layers located over the strained single-crystalline silicon layer. A memory opening fill structure extending through the alternating stack may include an epitaxial silicon-containing pedestal channel portion, and a vertical semiconductor channel, and a vertical stack of memory elements located adjacent to the vertical semiconductor channel Additionally or alternatively, a drain region can include a semiconductor drain portion and a nickel-aluminum-semiconductor alloy drain portion.
    Type: Grant
    Filed: August 4, 2020
    Date of Patent: November 8, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ashish Baraskar, Raghuveer S. Makala, Peter Rabkin
  • 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
  • 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
  • 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
  • Patent number: 11282857
    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: March 22, 2022
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ashish Baraskar, Peter Rabkin, Raghuveer S. Makala
  • Publication number: 20220045088
    Abstract: A memory device can include a strained single-crystalline silicon layer and an alternating stack of insulating layers and electrically conductive layers located over the strained single-crystalline silicon layer. A memory opening fill structure extending through the alternating stack may include an epitaxial silicon-containing pedestal channel portion, and a vertical semiconductor channel, and a vertical stack of memory elements located adjacent to the vertical semiconductor channel Additionally or alternatively, a drain region can include a semiconductor drain portion and a nickel-aluminum-semiconductor alloy drain portion.
    Type: Application
    Filed: August 4, 2020
    Publication date: February 10, 2022
    Inventors: Ashish BARASKAR, Raghuveer S. MAKALA, Peter RABKIN
  • Publication number: 20220045087
    Abstract: A memory device can include a strained single-crystalline silicon layer and an alternating stack of insulating layers and electrically conductive layers located over the strained single-crystalline silicon layer. A memory opening fill structure extending through the alternating stack may include an epitaxial silicon-containing pedestal channel portion, and a vertical semiconductor channel, and a vertical stack of memory elements located adjacent to the vertical semiconductor channel. Additionally or alternatively, a drain region can include a semiconductor drain portion and a nickel-aluminum-semiconductor alloy drain portion.
    Type: Application
    Filed: August 4, 2020
    Publication date: February 10, 2022
    Inventors: Ashish BARASKAR, Raghuveer S. MAKALA, Peter RABKIN
  • Patent number: 11244734
    Abstract: A memory apparatus and method of operation is provided. The apparatus includes memory cells coupled to a control circuit. The control circuit is configured to perform a first programming stage including iteratively programming each of the memory cells to first program states and verifying that the memory cells have a threshold voltage above one of a plurality of first verify voltages corresponding to the first program states. The first programming stage ends before all of the memory cells are verified thereby leaving a fraction of the memory cells below the one of the plurality of first verify voltages. The control circuit also performs a second programming stage including iteratively programming each of the memory cells to second program states and verifying that at least a predetermined number of the memory cells have the threshold voltage above one of a plurality of second verify voltages corresponding to the second program states.
    Type: Grant
    Filed: December 27, 2019
    Date of Patent: February 8, 2022
    Assignee: SanDisk Technologies LLC
    Inventors: Ashish Baraskar, Henry Chin, Ching-Huang Lu
  • Publication number: 20210375908
    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: Application
    Filed: May 29, 2020
    Publication date: December 2, 2021
    Inventors: Ashish BARASKAR, Peter RABKIN, Raghuveer S. MAKALA
  • Publication number: 20210375910
    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: Application
    Filed: May 29, 2020
    Publication date: December 2, 2021
    Inventors: Ashish BARASKAR, Peter RABKIN, Raghuveer S. MAKALA
  • Publication number: 20210375909
    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: Application
    Filed: May 29, 2020
    Publication date: December 2, 2021
    Inventors: Ashish BARASKAR, Peter RABKIN, Raghuveer S. MAKALA
  • Patent number: 11101288
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory openings vertically extending through the alternating stack, and memory stack structures extending through the alternating stack. Each of the memory stack structures contains a memory film and a vertical semiconductor channel. At least one of the electrically conductive layers contains a first conductive material portion having a respective inner sidewall that contacts a respective one of the memory films at a vertical interface, and a second conductive material portion that has a different composition from the first conductive material portion, and contacting the first electrically conductive material portion. The first conductive material portion has a lower work function than the second conductive material portion.
    Type: Grant
    Filed: December 11, 2019
    Date of Patent: August 24, 2021
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Dong-il Moon, Raghuveer S. Makala, Peng Zhang, Wei Zhao, Ashish Baraskar
  • Patent number: 11063063
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory openings vertically extending through the alternating stack, and memory stack structures extending through the alternating stack. Each of the memory stack structures contains a memory film and a vertical semiconductor channel. At least one of the electrically conductive layers contains a first conductive material portion having a respective inner sidewall that contacts a respective one of the memory films at a vertical interface, and a second conductive material portion that has a different composition from the first conductive material portion, and contacting the first electrically conductive material portion. The first conductive material portion has a lower work function than the second conductive material portion.
    Type: Grant
    Filed: December 11, 2019
    Date of Patent: July 13, 2021
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Dong-il Moon, Raghuveer S. Makala, Peng Zhang, Wei Zhao, Ashish Baraskar
  • Publication number: 20210202022
    Abstract: A memory apparatus and method of operation is provided. The apparatus includes memory cells coupled to a control circuit. The control circuit is configured to perform a first programming stage including iteratively programming each of the memory cells to first program states and verifying that the memory cells have a threshold voltage above one of a plurality of first verify voltages corresponding to the first program states. The first programming stage ends before all of the memory cells are verified thereby leaving a fraction of the memory cells below the one of the plurality of first verify voltages. The control circuit also performs a second programming stage including iteratively programming each of the memory cells to second program states and verifying that at least a predetermined number of the memory cells have the threshold voltage above one of a plurality of second verify voltages corresponding to the second program states.
    Type: Application
    Filed: December 27, 2019
    Publication date: July 1, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Ashish Baraskar, Henry Chin, Ching-Huang Lu
  • Publication number: 20210183883
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory openings vertically extending through the alternating stack, and memory stack structures extending through the alternating stack. Each of the memory stack structures contains a memory film and a vertical semiconductor channel. At least one of the electrically conductive layers contains a first conductive material portion having a respective inner sidewall that contacts a respective one of the memory films at a vertical interface, and a second conductive material portion that has a different composition from the first conductive material portion, and contacting the first electrically conductive material portion. The first conductive material portion has a lower work function than the second conductive material portion.
    Type: Application
    Filed: December 11, 2019
    Publication date: June 17, 2021
    Inventors: Yanli ZHANG, Dong-il MOON, Raghuveer S. MAKALA, Peng ZHANG, Wei ZHAO, Ashish BARASKAR
  • Publication number: 20210183882
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory openings vertically extending through the alternating stack, and memory stack structures extending through the alternating stack. Each of the memory stack structures contains a memory film and a vertical semiconductor channel. At least one of the electrically conductive layers contains a first conductive material portion having a respective inner sidewall that contacts a respective one of the memory films at a vertical interface, and a second conductive material portion that has a different composition from the first conductive material portion, and contacting the first electrically conductive material portion. The first conductive material portion has a lower work function than the second conductive material portion.
    Type: Application
    Filed: December 11, 2019
    Publication date: June 17, 2021
    Inventors: Yanli ZHANG, Dong-il MOON, Raghuveer S. MAKALA, Peng ZHANG, Wei ZHAO, Ashish BARASKAR
  • Patent number: 11037640
    Abstract: Techniques are provided to reduce neighbor word line interference and charge loss in a multi-pass program operation. In one implementation, the first pass of a multi-pass program operation uses one or more program pulses without performing associated verify tests. The memory cells may be programmed to different intermediate threshold voltage (Vth) distributions in the first program pass. Different bit line voltages can be used to obtain the different intermediate Vth distributions when the single program pulse is applied. In other cases, multiple program pulses are applied without performing verify tests. The intermediate Vth distributions can be provided for the memory cells assigned to the higher data states but not the lower data states, or for memory cells assigned to both the higher and lower data states.
    Type: Grant
    Filed: June 12, 2020
    Date of Patent: June 15, 2021
    Assignee: SanDisk Technologies LLC
    Inventors: Ashish Baraskar, Ching-Huang Lu, Vinh Diep, Yingda Dong