Patents by Inventor Venkatraman Prabhakar

Venkatraman Prabhakar 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: 10332599
    Abstract: A memory device that includes a non-volatile memory (NVM) array, divided into a flash memory portion and an electrically erasable programmable read-only memory (EEPROM) portion. The NVM array includes charge-trapping memory cells arranged in rows and columns, in which each memory cell has a memory transistor including an angled lightly doped drain (LDD) implant, and a select transistor including a shared source region with a halo implant. The flash memory portion and the EEPROM portion are disposed within one single semiconductor die. Other embodiments are also disclosed.
    Type: Grant
    Filed: March 12, 2018
    Date of Patent: June 25, 2019
    Assignee: LONGITUDE FLASH MEMORY SOLUTIONS LTD.
    Inventors: Gary Menezes, Krishnaswamy Ramkumar, Ali Keshavarzi, Venkatraman Prabhakar
  • Publication number: 20190147960
    Abstract: A memory device that includes a non-volatile memory (NVM) array, divided into a flash memory portion and an electrically erasable programmable read-only memory (EEPROM) portion. The NVM array includes charge-trapping memory cells arranged in rows and columns, in which each memory cell has a memory transistor including an angled lightly doped drain (LDD) implant, and a select transistor including a shared source region with a halo implant. The flash memory portion and the EEPROM portion are disposed within one single semiconductor die. Other embodiments are also disclosed.
    Type: Application
    Filed: March 12, 2018
    Publication date: May 16, 2019
    Applicant: Cypress Semiconductor Corporation
    Inventors: Gary Menezes, Krishnaswamy Ramkumar, Ali Keshavarzi, Venkatraman Prabhakar
  • Patent number: 10262747
    Abstract: A non-volatile memory that includes a shared source line configuration and methods of operating the same to reduce disturbs is provided. In one embodiment, the method includes coupling a first positive high voltage to a first global wordline in a first row of an array of memory cells, and coupling a second negative high voltage (VNEG) to a first bitline in a first column of the array to apply a bias to a non-volatile memory transistor in a selected memory cell to program the selected memory cell. A margin voltage having a magnitude less than VNEG is coupled to a second global wordline in a second row of the array, and an inhibit voltage coupled to a second bitline in a second column of the array.
    Type: Grant
    Filed: November 8, 2017
    Date of Patent: April 16, 2019
    Assignee: Cypress Semiconductor Corporation
    Inventors: Ryan T. Hirose, Igor G. Kouznetsov, Venkatraman Prabhakar, Kaveh Shakeri, Bogdan Georgescu
  • Publication number: 20190088487
    Abstract: A method to integrate silicon-oxide-nitride-oxide-silicon (SONOS) transistors into a complementary metal-oxide-semiconductor (CMOS) flow including a triple gate oxide structure. The memory device may include a non-volatile memory (NVM) transistor that has a charge-trapping layer and a blocking dielectric, a first field-effect transistor (FET) including a first gate oxide of a first thickness, a second FET including a second gate oxide of a second thickness, a third FET including a third gate oxide of a third thickness, in which the first thickness is greater than the second thickness and the second thickness is greater than the third thickness.
    Type: Application
    Filed: August 8, 2018
    Publication date: March 21, 2019
    Applicant: Cypress Semiconductor Corporation
    Inventors: Krishnaswamy Ramkumar, Igor Kouznetsov, Venkatraman Prabhakar, Ali Keshavarzi
  • Patent number: 10204691
    Abstract: A non-volatile memory that includes a shared source line configuration and methods of operating the same to reduce disturbs is provided. In one embodiment, the method includes coupling a first positive high voltage to a first global wordline in a first row of an array of memory cells, and coupling a second negative high voltage (VNEG) to a first bitline in a first column of the array to apply a bias to a non-volatile memory transistor in a selected memory cell to program the selected memory cell. A margin voltage having a magnitude less than VNEG is coupled to a second global wordline in a second row of the array, and an inhibit voltage coupled to a second bitline in a second column of the array.
    Type: Grant
    Filed: November 8, 2017
    Date of Patent: February 12, 2019
    Assignee: Cypress Semiconductor Corporation
    Inventors: Ryan T. Hirose, Igor G. Kouznetsov, Venkatraman Prabhakar, Kaveh Shakeri, Bogdan Georgescu
  • Patent number: 10192622
    Abstract: A method for operating a memory device includes the steps of providing a first voltage to a first transistor of a first memory cell and a third transistor of a second memory cell, providing a second voltage to a gate of a second transistor of the first memory cell and a gate of a fourth transistor of the second memory cell, and providing a third voltage to a gate of the first transistor of the first memory cell and a gate of the third transistor of the second memory cell. Other embodiments are also described.
    Type: Grant
    Filed: October 12, 2017
    Date of Patent: January 29, 2019
    Assignee: Cypress Semiconductor Corporation
    Inventors: Xiaojun Yu, Venkatraman Prabhakar, Igor Kouznetsov, Long Hinh, Bo Jin
  • Publication number: 20180358097
    Abstract: A method of performing an operation on a non-volatile memory (NVM) cell of a memory device is disclosed. The pass transistor of the NVM cell is an asymmetric transistor including a source with a halo implant. The source of the pass transistor is coupled to a common source line (CSL) that is shared among NVM cells of a sector of NVM cells. The operation may be performed by applying a first signal to a word line (WLS) coupled to a gate of a memory transistor of the NVM cell and applying a second signal to a bit line (BL) coupled to a drain of the memory transistor of the NVM cell.
    Type: Application
    Filed: July 3, 2018
    Publication date: December 13, 2018
    Applicant: Cypress Semiconductor Corporation
    Inventors: Sungkwon Lee, Venkatraman Prabhakar
  • Patent number: 10103244
    Abstract: A method of making a semiconductor device is provided. The method includes forming a deep well (DWELL) and a well (WELL) in a first region of a substrate, the WELL adjacent a surface of the substrate so that an interface between the WELL and DWELL is exposed on the surface of the substrate. A channel for a DEMOS transistor is formed in the first region over the interface and includes a first channel formed in the WELL and a second channel formed in the DWELL. A gate layer is deposited and patterned to concurrently form in the first region a first gate for the DEMOS transistor and in a second region a second gate for an ESD device. Dopants are implanted in the first and second regions to concurrently form a drain extension of the DEMOS transistor, and an ESD diffusion region of the ESD device.
    Type: Grant
    Filed: February 17, 2016
    Date of Patent: October 16, 2018
    Assignee: Cypress Semiconductor Corporation
    Inventors: Venkatraman Prabhakar, Igor Kouznetsov
  • Patent number: 10062573
    Abstract: A method to integrate silicon-oxide-nitride-oxide-silicon (SONOS) transistors into a complementary metal-oxide-semiconductor (CMOS) flow including a triple gate oxide structure. The memory device may include a non-volatile memory (NVM) transistor that has a charge-trapping layer and a blocking dielectric, a first field-effect transistor (FET) including a first gate oxide of a first thickness, a second FET including a second gate oxide of a second thickness, a third FET including a third gate oxide of a third thickness, in which the first thickness is greater than the second thickness and the second thickness is greater than the third thickness.
    Type: Grant
    Filed: August 22, 2017
    Date of Patent: August 28, 2018
    Assignee: Cypress Semiconductor Corporation
    Inventors: Krishnaswamy Ramkumar, Igor Kouznetsov, Venkatraman Prabhakar, Ali Keshavarzi
  • Patent number: 10020060
    Abstract: A method of performing an operation on a non-volatile memory (NVM) cell of a memory device is disclosed. The pass transistor of the NVM cell is an asymmetric transistor including a source with a halo implant. The source of the pass transistor is coupled to a common source line (CSL) that is shared among NVM cells of a sector of NVM cells. The operation may be performed by applying a first signal to a word line (WLS) coupled to a gate of a memory transistor of the NVM cell and applying a second signal to a bit line (BL) coupled to a drain of the memory transistor of the NVM cell.
    Type: Grant
    Filed: January 30, 2017
    Date of Patent: July 10, 2018
    Assignee: Cypress Semiconductor Corporation
    Inventors: Sungkwon Lee, Venkatraman Prabhakar
  • Patent number: 10002878
    Abstract: Methods of integrating complementary SONOS devices into a CMOS process flow are described. The method begins with depositing and patterning a first photoresist mask over a surface of a substrate to expose a N-SONOS region, and implanting a channel for a NSONOS device through a first pad oxide, followed by depositing and patterning a second photoresist mask to expose a P-SONOS region, and implanting a channel for a PSONOS device through a second pad oxide. Next, a number of Nwells are concurrently implanted for the PSONOS device and a PMOS device in a core region of the substrate. Finally, the first and second pad oxides, which were left in place to separate the P-SONOS region and the N-SONOS region from the first and second photoresist masks, are concurrently removed. In one embodiment, implanting the Nwells includes implanting a single, contiguous deep Nwell for the PSONOS and PMOS device.
    Type: Grant
    Filed: September 18, 2017
    Date of Patent: June 19, 2018
    Assignee: Cypress Semiconductor Corporation
    Inventors: Venkatraman Prabhakar, Krishnaswamy Ramkumar, Igor Kouznetsov
  • Patent number: 9997528
    Abstract: Methods of integrating complementary SONOS devices into a CMOS process flow are described. In one embodiment, the method begins with depositing a hardmask (HM) over a substrate including a first-SONOS region and a second-SONOS region. A first tunnel mask (TUNM) is formed over the HM exposing a first portion of the HM in the second-SONOS region. The first portion of the HM is etched, a channel for a first SONOS device implanted through a first pad oxide overlying the second-SONOS region and the first TUNM removed. A second TUNM is formed exposing a second portion of the HM in the first-SONOS region. The second portion of the HM is etched, a channel for a second SONOS device implanted through a second pad oxide overlying the first-SONOS region and the second TUNM removed. The first and second pad oxides are concurrently etched, and the HM removed.
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: June 12, 2018
    Assignee: Cypress Semiconductor Corporation
    Inventors: Venkatraman Prabhakar, Krishnaswamy Ramkumar, Igor Kouznetsov
  • Publication number: 20180082746
    Abstract: A method for operating a memory device includes the steps of providing a first voltage to a first transistor of a first memory cell and a third transistor of a second memory cell, providing a second voltage to a gate of a second transistor of the first memory cell and a gate of a fourth transistor of the second memory cell, and providing a third voltage to a gate of the first transistor of the first memory cell and a gate of the third transistor of the second memory cell. Other embodiments are also described.
    Type: Application
    Filed: October 12, 2017
    Publication date: March 22, 2018
    Applicant: Cypress Semiconductor Corporation
    Inventors: Xiaojun Yu, Venkatraman Prabhakar, Igor Kouznetsov, Long Hinh, Bo Jin
  • Patent number: 9922988
    Abstract: Memory devices and methods for forming the same are disclosed. In one embodiment, the device includes a non-volatile memory (NVM) transistor formed in a first region of a substrate, the NVM transistor comprising a channel and a gate stack on the substrate overlying the channel. The gate stack includes a dielectric layer on the substrate, a charge-trapping layer on the dielectric layer, an oxide layer overlying the charge-trapping layer, a first gate overlying the oxide layer, and a first silicide region overlying the first gate. The device includes a metal-oxide-semiconductor transistor formed in a second region of the substrate comprising a gate oxide overlying the substrate in the second region, a second gate overlying the gate oxide, and second silicide region overlying the second gate. A strain inducing structure overlies at least the NVM transistor and a surface of the substrate in the first region of the substrate.
    Type: Grant
    Filed: March 6, 2017
    Date of Patent: March 20, 2018
    Assignee: Cypress Semiconductor Corporation
    Inventors: Krishnaswamy Ramkumar, Igor G. Kouznetsov, Venkatraman Prabhakar
  • Publication number: 20180068735
    Abstract: A non-volatile memory that includes a shared source line configuration and methods of operating the same to reduce disturbs is provided. In one embodiment, the method includes coupling a first positive high voltage to a first global wordline in a first row of an array of memory cells, and coupling a second negative high voltage (VNEG) to a first bitline in a first column of the array to apply a bias to a non-volatile memory transistor in a selected memory cell to program the selected memory cell. A margin voltage having a magnitude less than VNEG is coupled to a second global wordline in a second row of the array, and an inhibit voltage coupled to a second bitline in a second column of the array.
    Type: Application
    Filed: November 8, 2017
    Publication date: March 8, 2018
    Applicant: Cypress Semiconductor Corporation
    Inventors: Ryan T. Hirose, Igor G. Kouznetsov, Venkatraman Prabhakar, Kaveh Shakeri, Bogdan Georgescu
  • Patent number: 9893172
    Abstract: A method of forming a transistor is described. In one embodiment the method includes: forming a channel of a transistor in a surface of a substrate; forming a dielectric stack including a first oxide layer overlying the surface of the substrate, a middle layer comprising nitride overlying the first oxide layer and a second oxide layer overlying the middle layer; forming over the dielectric stack a mask exposing source and drain (S/D) regions of the transistor; etching the dielectric stack through the mask to thin the dielectric stack by removing the second oxide layer and at least a first portion of the middle layer in S/D regions of the transistor; and implanting dopants into S/D regions of the transistor through the thinned dielectric stack to form a lightly-doped drain (LDD) adjacent to the channel of the transistor. Other embodiments are also described.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: February 13, 2018
    Assignee: Cypress Semiconductor Corporation
    Inventors: Krishnaswamy Ramkumar, Venkatraman Prabhakar
  • Publication number: 20180040625
    Abstract: Methods of integrating complementary SONOS devices into a CMOS process flow are described. The method begins with depositing and patterning a first photoresist mask over a surface of a substrate to expose a N-SONOS region, and implanting a channel for a NSONOS device through a first pad oxide, followed by depositing and patterning a second photoresist mask to expose a P-SONOS region, and implanting a channel for a PSONOS device through a second pad oxide. Next, a number of Nwells are concurrently implanted for the PSONOS device and a PMOS device in a core region of the substrate. Finally, the first and second pad oxides, which were left in place to separate the P-SONOS region and the N-SONOS region from the first and second photoresist masks, are concurrently removed. In one embodiment, implanting the Nwells includes implanting a single, contiguous deep Nwell for the PSONOS and PMOS device.
    Type: Application
    Filed: September 18, 2017
    Publication date: February 8, 2018
    Inventors: Venkatraman Prabhakar, Krishnaswamy Ramkumar, Igor Kouznetsov
  • Patent number: 9865711
    Abstract: A method of forming a transistor is described. In one embodiment the method includes: forming a channel of a transistor in a surface of a substrate; forming a dielectric stack including a first oxide layer overlying the surface of the substrate, a middle layer comprising nitride overlying the first oxide layer and a second oxide layer overlying the middle layer; forming over the dielectric stack a mask exposing source and drain (S/D) regions of the transistor; etching the dielectric stack through the mask to thin the dielectric stack by removing the second oxide layer and at least a first portion of the middle layer in S/D regions of the transistor; and implanting dopants into S/D regions of the transistor through the thinned dielectric stack to form a lightly-doped drain (LDD) adjacent to the channel of the transistor. Other embodiments are also described.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: January 9, 2018
    Assignee: Cypress Semiconductor Corporation
    Inventors: Krishnaswamy Ramkumar, Venkatraman Prabhakar
  • Patent number: 9847137
    Abstract: A non-volatile memory and methods of operating the same to reduce disturbs is provided. In one embodiment, the method includes coupling a first positive high voltage to a first global wordline in a first row of an array of memory cells, and coupling a second negative high voltage (VNEG) to a first bitline in a first column of the array to apply a bias to a non-volatile memory transistor in a selected memory cell to program the selected memory cell. A margin voltage having a magnitude less than VNEG is coupled to a second global wordline in a second row of the array, and an inhibit voltage coupled to a second bitline in a second column of the array to reduce a bias applied to a non-volatile memory transistor in an unselected memory cell to reduce program disturb of data programmed in the unselected memory cell due to programming.
    Type: Grant
    Filed: August 30, 2016
    Date of Patent: December 19, 2017
    Assignee: Cypress Semiconductor Corporation
    Inventors: Ryan T. Hirose, Igor G. Kouznetsov, Venkatraman Prabhakar, Kaveh Shakeri, Bogdan Georgescu
  • Patent number: 9818484
    Abstract: Systems, methods, and apparatus are disclosed for implementing memory cells having common source lines. The methods may include receiving a first voltage at a first transistor. The first transistor may be coupled to a second transistor and included in a first memory cell. The methods include receiving a second voltage at a third transistor. The third transistor may be coupled to a fourth transistor and included in a second memory cell. The first and second memory cells may be coupled to a common source line. The methods include receiving a third voltage at a gate of the second transistor and a gate of the fourth transistor that may cause them to operate in cutoff mode. The methods may include receiving a fourth voltage at a gate of the first transistor. The fourth voltage may cause a change in a charge storage layer included in the first transistor.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: November 14, 2017
    Assignee: Cypress Semiconductor Corporation
    Inventors: Xiaojun Yu, Venkatraman Prabhakar, Igor G. Kouznetsov, Long T Hinh, Bo Jin