Patents by Inventor Sujith Subramanian

Sujith Subramanian 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: 20240206145
    Abstract: The present disclosure relates to static random access memory (SRAM). In particular, the disclosure provides a stacked SRAM cell, and a method for fabricating the stacked SRAM cell. The stacked SRAM cell comprises two first transistor structures and two second transistor structures, which form a pair of cross-coupled inverters, an comprises one or two pass gate (PG) transistor structures. Further, the stacked SRAM cell comprises a first power rail and/or a second power rail arranged above the transistor structures, wherein the first power rail is connected by respective first vias to the first transistor structures from above, and/or the second power rail is connected by respective second vias to the second transistor structures from above. The SRAM cell also comprises one or two bit lines arranged below the PG transistor structures. Each bit line is connected by a respective third via to one PG transistor structure from below.
    Type: Application
    Filed: December 19, 2023
    Publication date: June 20, 2024
    Inventors: Hsiao-Hsuan Liu, Shairfe Muhammad Salahuddin, Boon Teik Chan, Sujith Subramanian
  • Publication number: 20240128124
    Abstract: A method for forming a stacked transistor device is disclosed, in which a nanosheet field-effect transistor (FET) structure and a fin FET structure are formed. The method comprises forming a first fin structure and a second fin structure from a vertical stack, wherein the second fin structure is arranged above the first fin structure, and wherein the vertical stack comprises a middle layer arranged between the first and second fin structures. The method further comprises forming, from above, a gate structure across a channel region of the second fin structure, forming, from below, a gate structure across a channel region of the first fin structure, and forming source and drain regions for the first and second fin structures.
    Type: Application
    Filed: June 28, 2023
    Publication date: April 18, 2024
    Inventor: Sujith Subramanian
  • Publication number: 20230420544
    Abstract: In one aspect, a method of forming a semiconductor device including a plurality of stacked transistor devices having a bottom transistor device and a top transistor device can include: forming a plurality of parallel fin structures on a substrate; forming a sacrificial gate across the fin structures; forming bottom source/drain bodies for each bottom transistor device by epitaxy; forming a bottom dummy contact layer covering the bottom source/drain bodies; forming top source/drain bodies for each top transistor device over the bottom dummy contact layer by epitaxy; depositing an insulating material over the bottom dummy contact layer and the top source/drain bodies; replacing the sacrificial gate with a functional gate stack by a replacement metal gate process; patterning holes extending through the insulating material, with each hole exposing an upper surface portion of the bottom dummy contact layer; replacing the bottom dummy contact layer with one or more contact metals, which can include etching the dumm
    Type: Application
    Filed: June 26, 2023
    Publication date: December 28, 2023
    Inventors: Hans Mertens, Sujith Subramanian
  • Publication number: 20230187539
    Abstract: A method for forming a first transistor structure from a first channel layer and a second transistor structure from a second channel layer is disclosed. The first channel layer and the second channel layer are vertically stacked on a substrate. The method includes processing the first transistor structure from above, followed by processing the second transistor structure from the backside.
    Type: Application
    Filed: December 9, 2022
    Publication date: June 15, 2023
    Inventors: Sujith Subramanian, Hans Mertens, Steven Demuynck
  • Publication number: 20230187528
    Abstract: The disclosed method includes forming an initial layer stack comprising a sacrificial layer of a first semiconductor material and over the sacrificial layer a channel layer of a second semiconductor material, forming a fin structures by patterning trenches in the initial layer stack, forming an anchoring structure extending across the fin structures, and while the channel layers are anchored by the anchoring structure: removing the sacrificial layers by a selective etching of the first semiconductor material, thereby forming a longitudinal cavity underneath the channel layer of each fin structure, and depositing an insulating material to fill the cavities, wherein the insulating material is formed of a flowable dielectric, and subsequently recessing the at least one anchoring structure and the insulating material to a level below the cavities such that the insulating material remains in the cavities to form insulating layers underneath the channel layers of each fin structure.
    Type: Application
    Filed: December 13, 2022
    Publication date: June 15, 2023
    Inventors: Sujith Subramanian, Steven Demuynck, Hans Mertens