Patents by Inventor Ishan Wathuthanthri

Ishan Wathuthanthri 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: 20250048719
    Abstract: A method of integrating a phase change switch (PCS) into a Bipolar (Bi)/Complementary Metal Oxide Semiconductor (CMOS) (BiCMOS) process, comprises providing a base structure including BiCMOS circuitry on a semiconductor substrate, and forming on the base structure a dielectric contact window layer having metal through-plugs that contact the BiCMOS circuitry. The method includes constructing the PCS on the contact window layer. The PCS includes: a phase change region, between ohmic contacts on the phase change region, to operate as a switch controlled by heat. The method further includes forming, on the contact window layer and the PCS, a stack of alternating patterned metal layers and dielectric layers that interconnect the patterned metal layers, such that the stack connects a first of the ohmic contacts to the BiCMOS circuitry and provides connections to a second of the ohmic contacts and to the resistive heater.
    Type: Application
    Filed: October 18, 2024
    Publication date: February 6, 2025
    Inventors: Patrick B. Shea, Robert M. Young, Keith H. Chung, Andris Ezis, Ishan Wathuthanthri
  • Patent number: 12150316
    Abstract: A method of integrating a phase change switch (PCS) into a Bipolar (Bi)/Complementary Metal Oxide Semiconductor (CMOS) (BiCMOS) process, comprises providing a base structure including BiCMOS circuitry on a semiconductor substrate, and forming on the base structure a dielectric contact window layer having metal through-plugs that contact the BiCMOS circuitry. The method includes constructing the PCS on the contact window layer. The PCS includes: a phase change region, between ohmic contacts on the phase change region, to operate as a switch controlled by heat. The method further includes forming, on the contact window layer and the PCS, a stack of alternating patterned metal layers and dielectric layers that interconnect the patterned metal layers, such that the stack connects a first of the ohmic contacts to the BiCMOS circuitry and provides connections to a second of the ohmic contacts and to the resistive heater.
    Type: Grant
    Filed: November 7, 2022
    Date of Patent: November 19, 2024
    Assignee: Northrop Grumman Systems Corporation
    Inventors: Patrick B. Shea, Robert M. Young, Keith H. Chung, Andris Ezis, Ishan Wathuthanthri
  • Publication number: 20230056901
    Abstract: A method of integrating a phase change switch (PCS) into a Bipolar (Bi)/Complementary Metal Oxide Semiconductor (CMOS) (BiCMOS) process, comprises providing a base structure including BiCMOS circuitry on a semiconductor substrate, and forming on the base structure a dielectric contact window layer having metal through-plugs that contact the BiCMOS circuitry. The method includes constructing the PCS on the contact window layer. The PCS includes: a phase change region, between ohmic contacts on the phase change region, to operate as a switch controlled by heat. The method further includes forming, on the contact window layer and the PCS, a stack of alternating patterned metal layers and dielectric layers that interconnect the patterned metal layers, such that the stack connects a first of the ohmic contacts to the BiCMOS circuitry and provides connections to a second of the ohmic contacts and to the resistive heater.
    Type: Application
    Filed: November 7, 2022
    Publication date: February 23, 2023
    Inventors: Patrick B. Shea, Robert M. Young, Keith H. Chung, Andris Ezis, Ishan Wathuthanthri
  • Patent number: 11522010
    Abstract: A method of integrating a phase change switch (PCS) into a Bipolar (Bi)/Complementary Metal Oxide Semiconductor (CMOS) (BiCMOS) process, comprises providing a base structure including BiCMOS circuitry on a semiconductor substrate, and forming on the base structure a dielectric contact window layer having metal through-plugs that contact the BiCMOS circuitry. The method includes constructing the PCS on the contact window layer. The PCS includes: a phase change region, between ohmic contacts on the phase change region, to operate as a switch controlled by heat. The method further includes forming, on the contact window layer and the PCS, a stack of alternating patterned metal layers and dielectric layers that interconnect the patterned metal layers, such that the stack connects a first of the ohmic contacts to the BiCMOS circuitry and provides connections to a second of the ohmic contacts and to the resistive heater.
    Type: Grant
    Filed: August 19, 2019
    Date of Patent: December 6, 2022
    Assignee: Northrop Grumman Systems Corporation
    Inventors: Patrick B. Shea, Robert M. Young, Keith H. Chung, Andris Ezis, Ishan Wathuthanthri
  • Patent number: 11342440
    Abstract: A transistor is provided that comprises a source region overlying a base structure, a drain region overlying the base structure, and a block of semiconducting material overlying the base structure and being disposed between the source region and the drain region. The block of semiconducting material comprises a gate controlled region adjacent the source region, and a drain access region disposed between the gate controlled region and the drain region. The drain access region is formed of a plurality of semiconducting material ridges spaced apart from one another by non-channel trench openings, wherein at least a portion of the non-channel trench openings being filled with a doped material to provide a depletion region to improve breakdown voltage of the transistor.
    Type: Grant
    Filed: July 22, 2019
    Date of Patent: May 24, 2022
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Ishan Wathuthanthri, Ken Alfred Nagamatsu, William J. Sweet, James T. Kelliher, John S. Mason, Jr., Jonah Paul Sengupta
  • Publication number: 20210057487
    Abstract: A method of integrating a phase change switch (PCS) into a Bipolar (Bi)/Complementary Metal Oxide Semiconductor (CMOS) (BiCMOS) process, comprises providing a base structure including BiCMOS circuitry on a semiconductor substrate, and forming on the base structure a dielectric contact window layer having metal through-plugs that contact the BiCMOS circuitry. The method includes constructing the PCS on the contact window layer. The PCS includes: a phase change region, between ohmic contacts on the phase change region, to operate as a switch controlled by heat. The method further includes forming, on the contact window layer and the PCS, a stack of alternating patterned metal layers and dielectric layers that interconnect the patterned metal layers, such that the stack connects a first of the ohmic contacts to the BiCMOS circuitry and provides connections to a second of the ohmic contacts and to the resistive heater.
    Type: Application
    Filed: August 19, 2019
    Publication date: February 25, 2021
    Inventors: Patrick B. Shea, Robert M. Young, Keith H. Chung, Andris Ezis, Ishan Wathuthanthri
  • Publication number: 20210028295
    Abstract: A transistor is provided that comprises a source region overlying a base structure, a drain region overlying the base structure, and a block of semiconducting material overlying the base structure and being disposed between the source region and the drain region. The block of semiconducting material comprises a gate controlled region adjacent the source region, and a drain access region disposed between the gate controlled region and the drain region. The drain access region is formed of a plurality of semiconducting material ridges spaced apart from one another by non-channel trench openings, wherein at least a portion of the non-channel trench openings being filled with a doped material to provide a depletion region to improve breakdown voltage of the transistor.
    Type: Application
    Filed: July 22, 2019
    Publication date: January 28, 2021
    Applicant: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: ISHAN WATHUTHANTHRI, KEN ALFRED NAGAMATSU, WILLIAM J. SWEET, JAMES T. KELLIHER, JOHN S. MASON, JR., JONAH PAUL SENGUPTA
  • Patent number: 8681315
    Abstract: A two-beam interference lithography system offers large-area nanopatterning with tunability of pattern periodicities. The tunable feature is achieved by placing two rotatable mirrors in the two expanded beam paths which can conveniently be regulated for the designed pattern periodicities. While the effective interference pattern coverage is mainly determined by the optical coherence length and mirror size, the minimum pattern coverage area is as large as the effective coherence length of the laser and the selected mirror size over a wide range of periodicities.
    Type: Grant
    Filed: July 12, 2012
    Date of Patent: March 25, 2014
    Assignee: The Trustees of the Stevens Institute of Technology
    Inventors: Weidong Mao, Ishan Wathuthanthri, Chang-Hwan Choi
  • Publication number: 20130017498
    Abstract: A two-beam interference lithography system offers large-area nanopatterning with tunability of pattern periodicities. The tunable feature is achieved by placing two rotatable mirrors in the two expanded beam paths which can conveniently be regulated for the designed pattern periodicities. While the effective interference pattern coverage is mainly determined by the optical coherence length and mirror size, the minimum pattern coverage area is as large as the effective coherence length of the laser and the selected mirror size over a wide range of periodicities.
    Type: Application
    Filed: July 12, 2012
    Publication date: January 17, 2013
    Inventors: Weidong Mao, Ishan Wathuthanthri, Chang-Hwan Choi