Patents by Inventor Prasad Venkatraman

Prasad Venkatraman 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: 20240088237
    Abstract: In an example, a semiconductor device includes an active trench region and an intersecting trench. The active region includes an active shield electrode and the intersecting trench includes an intersecting shield electrode. A coupling trench region connects the active trench region to the intersecting trench region. The coupling trench region includes a coupling shield electrode. The coupling shield electrode and the intersecting shield electrode are provided proximate to a termination mesa region. One or more of the coupling shield electrode or the intersecting shield electrode is thinner than the active shield electrode. The thinner shield electrode reduces depletion in the termination mesa region to improve, among other things, breakdown voltage performance.
    Type: Application
    Filed: August 23, 2023
    Publication date: March 14, 2024
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Balaji PADMANABHAN, Prasad VENKATRAMAN
  • Patent number: 11888060
    Abstract: A MOSFET device die includes an active area formed on a semiconductor substrate. The active area includes a first active area portion and a second active area portion. At least one mesa is formed in the semiconductor substrate extending in a longitudinal direction through the active area. The at least one mesa includes a channel region extending in a longitudinal direction. The channel region includes low threshold voltage channel portions and high threshold voltage channel portions. The first active area portion includes the channel portions in a first ratio of low threshold voltage channel portions to high threshold voltage channel portions, and the second active area portion includes channel portions in a second ratio of low threshold voltage channel portions to high threshold voltage channel portions. The first ratio is larger than the second ratio.
    Type: Grant
    Filed: September 1, 2021
    Date of Patent: January 30, 2024
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventor: Prasad Venkatraman
  • Publication number: 20230352577
    Abstract: An accumulation MOSFET includes a plurality of device cells. Each device cell includes a mesa adjoining a vertical trench is disposed in a doped semiconductor substrate. The mesa has a top mesa portion disposed on a bottom mesa portion. The top mesa portion has a width that is narrower than a width of the bottom mesa portion. The vertical trench adjoining the mesa has a top trench portion and a bottom trench portion. The top trench portion has a width that is wider than a width of the bottom trench portion. A dielectric is disposed on a sidewall of the vertical trench. A gate electrode disposed in the top trench portion forms an accumulation channel region in the top mesa portion and a shield electrode disposed in the bottom trench portion forms a depletion drift region in the bottom mesa portion.
    Type: Application
    Filed: February 17, 2023
    Publication date: November 2, 2023
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Peter MOENS, Balaji PADMANABHAN, Dean E. PROBST, Prasad VENKATRAMAN, Tirthajyoti SARKAR, Gary Horst LOECHELT
  • Patent number: 11742420
    Abstract: In one embodiment, a semiconductor device is formed having a plurality of active trenches formed within an active region of the semiconductor device. A first insulator is formed along at least a portion of sidewalls of each active trench. A perimeter termination trench is formed that surrounds the active region. The perimeter termination trench is formed having a first sidewall that is adjacent the active region and a second sidewall that is opposite the first sidewall. An insulator is formed along the second sidewall that has a thickness is greater than an insulator that is formed along the first sidewall.
    Type: Grant
    Filed: November 23, 2021
    Date of Patent: August 29, 2023
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Dean E. Probst, Peter A. Burke, Prasad Venkatraman
  • Publication number: 20230113308
    Abstract: In a general aspect, a vertical transistor can include a semiconductor region of a first conductivity type, and a plurality of perpendicularly intersecting trenches having a shielded gate structure of the vertical transistor disposed therein. A mesa of the semiconductor region can be defined by the plurality of perpendicularly intersecting trenches. The mesa can include a proximal end portion having a first doping concentration of the first conductivity type, a distal end portion having the first doping concentration of the first conductivity type, and a central portion disposed between the proximal end portion and the distal end portion. The central portion can have a second doping concentration of the first conductivity type that is less than the first doping concentration.
    Type: Application
    Filed: October 5, 2022
    Publication date: April 13, 2023
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Balaji PADMANABHAN, Prasad VENKATRAMAN, Sauvik CHOWDHURY
  • Publication number: 20230106080
    Abstract: A method includes forming an ion-implanted capping layer in a first epitaxial layer disposed on a silicon substrate. The ion-implanted capping layer is doped with a second dopant of a same conductivity type as a first dopant in the silicon substrate. The second dopant has a lower diffusivity than the diffusivity of the first dopant. The ion-implanted capping layer has a thickness configured to contain up-diffusion of the first dopant from the silicon wafer in the first epitaxial layer in thermal processes for fabricating a vertical MOSFET device in the substrate. The ion-implanted capping layer is configured to limit up-diffusion of the first dopant from the silicon wafer through the ion-implanted capping layer into a second epitaxial layer such that a concentration of the first dopant in the second epitaxial layer is lower than a concentration of the first dopant in the first epitaxial layer.
    Type: Application
    Filed: December 8, 2022
    Publication date: April 6, 2023
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventor: Prasad VENKATRAMAN
  • Patent number: 11621331
    Abstract: A circuit and physical structure can help to counteract non-linear COSS associated with power transistors that operate at higher switching speeds and lower RDSON. In an embodiment, a component with a pn junction can be coupled to an n-channel IGFET. The component can include a p-channel IGFET, a pnp bipolar transistor, or both. A gate/capacitor electrode can be within a trench that is adjacent to the active regions of the component and n-channel IGFET, where the active regions can be within a semiconductor pillar. The combination of a conductive member and the semiconductor pillar of the component can be a charge storage component. The physical structure may include a compensation region, a barrier doped region, or both. In a particular embodiment, doped surface regions can be coupled to a buried conductive region without the use of a topside interconnect or a deep collector type of structure.
    Type: Grant
    Filed: September 10, 2020
    Date of Patent: April 4, 2023
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Gary Horst Loechelt, Balaji Padmanabhan, Dean E. Probst, Tirthajyoti Sarkar, Prasad Venkatraman, Muh-Ling Ger
  • Publication number: 20230065659
    Abstract: A MOSFET device die includes an active area formed on a semiconductor substrate. The active area includes a first active area portion and a second active area portion. At least one mesa is formed in the semiconductor substrate extending in a longitudinal direction through the active area. The at least one mesa includes a channel region extending in a longitudinal direction. The channel region includes low threshold voltage channel portions and high threshold voltage channel portions. The first active area portion includes the channel portions in a first ratio of low threshold voltage channel portions to high threshold voltage channel portions, and the second active area portion includes channel portions in a second ratio of low threshold voltage channel portions to high threshold voltage channel portions. The first ratio is larger than the second ratio.
    Type: Application
    Filed: September 1, 2021
    Publication date: March 2, 2023
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventor: Prasad VENKATRAMAN
  • Patent number: 11552017
    Abstract: In a general aspect, a transistor can include a trench disposed in a semiconductor region and a gate electrode disposed in an upper portion of the trench. The gate electrode can include a first and second gate electrode segments. The transistor can also include a shield electrode having a first shield electrode portion disposed in a lower portion of the trench, and a second shield electrode portion orthogonally extending from the first shield electrode portion in the lower portion of the trench to the upper portion of the trench. The first shield electrode portion can be disposed below the first and second gate electrode segments, and the second shield electrode portion can being disposed between the first and second gate electrode segments. The transistor can also include a patterned buried conductor layer. The first and second gate electrode segments can be electrically coupled via the patterned buried conductor layer.
    Type: Grant
    Filed: January 25, 2021
    Date of Patent: January 10, 2023
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Prasad Venkatraman, Gary Horst Loechelt
  • Patent number: 11527618
    Abstract: A substrate for fabricating a MOSFET device includes a first epitaxial layer disposed on a silicon wafer. The silicon wafer is doped with a first dopant. A second epitaxial layer is disposed on the first epitaxial layer. An ion-implanted capping layer is disposed in the first epitaxial layer. The ion-implanted capping layer is doped with a second dopant. The first dopant has a diffusion coefficient in silicon higher than a diffusion coefficient of the second dopant in silicon. The ion-implanted capping layer is configured to limit up-diffusion of the first dopant from the silicon wafer into the second epitaxial layer.
    Type: Grant
    Filed: October 1, 2020
    Date of Patent: December 13, 2022
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventor: Prasad Venkatraman
  • Publication number: 20220310802
    Abstract: A method includes defining a plurality of trenches of a first type that extend in a longitudinal direction in a semiconductor substrate, and defining a trench of a second type extending in a lateral direction and intersecting the plurality of trenches of the first type. The trench of the second type is in fluid communication with each of the intersected plurality of trenches of the first type. The method further includes disposing a shield poly layer in the plurality of trenches of the first type and the trench of the second type, disposing an inter-poly dielectric layer and a gate poly layer above the shield poly layer in the plurality of trenches of the first type and the trench of the second type, and forming an electrical contact to the shield poly layer through an opening in the inter-poly dielectric layer and the gate poly layer disposed in the trench of the second type.
    Type: Application
    Filed: March 21, 2022
    Publication date: September 29, 2022
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Prasad VENKATRAMAN, Peter BURKE, Gary Horst LOECHELT, Balaji PADMANABHAN, Emily M. LINEHAN
  • Patent number: 11411077
    Abstract: An electronic device can include doped regions and a trench disposed between the doped regions, wherein the trench can include a conductive member. In an embodiment, a parasitic transistor can include doped regions as drain/source regions and the conductive member as a gate electrode. A semiconductor material can lie along a bottom or sidewall of the trench and be a channel region of the parasitic transistor. The voltage on the gate electrode or the dopant concentration can be selected so that the channel region does not reach inversion during the normal operation of the electronic device.
    Type: Grant
    Filed: September 10, 2020
    Date of Patent: August 9, 2022
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Gary Horst Loechelt, Balaji Padmanabhan, Dean E. Probst, Tirthajyoti Sarkar, Prasad Venkatraman, Muh-Ling Ger
  • Publication number: 20220238427
    Abstract: In a general aspect, a transistor can include a trench disposed in a semiconductor region and a gate electrode disposed in an upper portion of the trench. The gate electrode can include a first and second gate electrode segments. The transistor can also include a shield electrode having a first shield electrode portion disposed in a lower portion of the trench, and a second shield electrode portion orthogonally extending from the first shield electrode portion in the lower portion of the trench to the upper portion of the trench. The first shield electrode portion can be disposed below the first and second gate electrode segments, and the second shield electrode portion can being disposed between the first and second gate electrode segments. The transistor can also include a patterned buried conductor layer. The first and second gate electrode segments can be electrically coupled via the patterned buried conductor layer.
    Type: Application
    Filed: January 25, 2021
    Publication date: July 28, 2022
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Prasad VENKATRAMAN, Gary Horst LOECHELT
  • Publication number: 20220085204
    Abstract: In one embodiment, a semiconductor device is formed having a plurality of active trenches formed within an active region of the semiconductor device. A first insulator is formed along at least a portion of sidewalls of each active trench. A perimeter termination trench is formed that surrounds the active region. The perimeter termination trench is formed having a first sidewall that is adjacent the active region and a second sidewall that is opposite the first sidewall. An insulator is formed along the second sidewall that has a thickness is greater than an insulator that is formed along the first sidewall.
    Type: Application
    Filed: November 23, 2021
    Publication date: March 17, 2022
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Dean E. PROBST, Peter A. BURKE, Prasad VENKATRAMAN
  • Publication number: 20220077282
    Abstract: An electronic device can include doped regions and a trench disposed between the doped regions, wherein the trench can include a conductive member. In an embodiment, a parasitic transistor can include doped regions as drain/source regions and the conductive member as a gate electrode. A semiconductor material can lie along a bottom or sidewall of the trench and be a channel region of the parasitic transistor. The voltage on the gate electrode or the dopant concentration can be selected so that the channel region does not reach inversion during the normal operation of the electronic device.
    Type: Application
    Filed: September 10, 2020
    Publication date: March 10, 2022
    Applicant: Semiconductor Components Industries, LLC
    Inventors: Gary Horst Loechelt, Balaji Padmanabhan, Dean E. Probst, Tirthajyoti Sarkar, Prasad Venkatraman, Muh-Ling Ger
  • Publication number: 20220077290
    Abstract: A circuit and physical structure can help to counteract non-linear COSS associated with power transistors that operate at higher switching speeds and lower RDSON. In an embodiment, a component with a pn junction can be coupled to an n-channel IGFET. The component can include a p-channel IGFET, a pnp bipolar transistor, or both. A gate/capacitor electrode can be within a trench that is adjacent to the active regions of the component and n-channel IGFET, where the active regions can be within a semiconductor pillar. The combination of a conductive member and the semiconductor pillar of the component can be a charge storage component. The physical structure may include a compensation region, a barrier doped region, or both. In a particular embodiment, doped surface regions can be coupled to a buried conductive region without the use of a topside interconnect or a deep collector type of structure.
    Type: Application
    Filed: September 10, 2020
    Publication date: March 10, 2022
    Applicant: Semiconductor Components Industries, LLC
    Inventors: Gary Horst Loechelt, Balaji Padmanabhan, Dean E. Probst, Tirthajyoti Sarkar, Prasad Venkatraman, Muh-Ling Ger
  • Patent number: 11257916
    Abstract: Systems and methods of the disclosed embodiments include an electronic device that has a gate electrode for supplying a gate voltage, a source, a drain, and a channel doped to enable a current to flow from the drain to the source when a voltage is applied to the gate electrode. The electronic device may also include a gate insulator between the channel and the gate electrode. The gate insulator may include a first gate insulator section including a first thickness, and a second gate insulator section including a second thickness that is less than the first thickness. The gate insulator sections thereby improve the safe operating area by enabling the current to flow through the second gate insulator section at a lower voltage than the first gate insulator section.
    Type: Grant
    Filed: June 24, 2019
    Date of Patent: February 22, 2022
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Balaji Padmanabhan, Prasad Venkatraman, Zia Hossain, Donald Zaremba, Gordon M. Grivna, Alexander Young
  • Publication number: 20220020851
    Abstract: A substrate for fabricating a MOSFET device includes a first epitaxial layer disposed on a silicon wafer. The silicon wafer is doped with a first dopant. A second epitaxial layer is disposed on the first epitaxial layer. An ion-implanted capping layer is disposed in the first epitaxial layer. The ion-implanted capping layer is doped with a second dopant. The first dopant has a diffusion coefficient in silicon higher than a diffusion coefficient of the second dopant in silicon. The ion-implanted capping layer is configured to limit up-diffusion of the first dopant from the silicon wafer into the second epitaxial layer.
    Type: Application
    Filed: October 1, 2020
    Publication date: January 20, 2022
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventor: Prasad VENKATRAMAN
  • Patent number: 11227946
    Abstract: A device has an active area made of an array of first type of device cells and a gate or shield contact area made of an array of a second type of device cells that are laid out at a wider pitch than the array of first type of device cells. Each first type of device cell in the active area includes a trench that contains a gate electrode and an adjoining mesa that contains the drain, source, body, and channel regions of the device. Each second type of device cell in the gate or shield contact area includes a trench that is wider and deeper than the trench in the first type device cell.
    Type: Grant
    Filed: March 20, 2020
    Date of Patent: January 18, 2022
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Prasad Venkatraman, Dean E. Probst
  • Patent number: 11217689
    Abstract: In one embodiment, a semiconductor device is formed having a plurality of active trenches formed within an active region of the semiconductor device. A first insulator is formed along at least a portion of sidewalls of each active trench. A perimeter termination trench is formed that surrounds the active region. The perimeter termination trench is formed having a first sidewall that is adjacent the active region and a second sidewall that is opposite the first sidewall. An insulator is formed along the second sidewall that has a thickness is greater than an insulator that is formed along the first sidewall.
    Type: Grant
    Filed: August 20, 2019
    Date of Patent: January 4, 2022
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Dean E. Probst, Peter A. Burke, Prasad Venkatraman