Patents by Inventor Ashim Dutta

Ashim Dutta 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: 20210151377
    Abstract: A method of forming a self-aligned top via is provided. The method includes forming a metallization layer on a substrate, and forming a hardmask layer on the metallization layer. The method further includes forming a pair of adjacent parallel mandrels on the hardmask layer with sidewall spacers on opposite sides of each mandrel. The method further includes forming a planarization layer on the exposed portions of the hardmask layer, mandrels, and sidewall spacers, and forming an opening in the planarization layer aligned between the adjacent parallel mandrels. The method further includes forming a spacer layer in the opening, and removing portions of the spacer layer to form a pair of spacer plugs between sections of the sidewall spacers.
    Type: Application
    Filed: November 15, 2019
    Publication date: May 20, 2021
    Inventors: Chi-Chun Liu, John C. Arnold, Dominik Metzler, Nelson Felix, Ashim Dutta
  • Publication number: 20210134883
    Abstract: A semiconductor device structure includes a metallization stack that has one or more patterned metal layers in a logic area and a memory area. At least one memory device is disposed above the metallization stack. A first level logic metal layer is coupled to a patterned metal layer of the one or more patterned metal layers in the logic area. A first level memory metal layer is formed above the first level logic metal layer and is coupled to a top electrode of the memory device stack. A distance between the one or more patterned metal layers in the logic area and the first level logic metal layer is smaller than the distance between the one or more patterned metal layers in the memory area and the first level memory metal layer.
    Type: Application
    Filed: November 4, 2019
    Publication date: May 6, 2021
    Inventors: Ashim DUTTA, Chih-Chao YANG, Daniel Charles EDELSTEIN, John ARNOLD, Theodorus E. STANDAERT
  • Publication number: 20210125865
    Abstract: Techniques for self-aligned top via formation at line ends are provided. In one aspect, a method of forming self-aligned vias at line ends includes: patterning (even/odd) metal lines including using a (first/second) hardmask; cutting the hardmask and a select metal line, even or odd, using a cut mask having a window that exposes the hardmask over a cut region of the select metal line; enlarging the window to expose the hardmask on either side of the cut region; selectively etching the hardmask using the enlarged window to form a T-shaped cavity within the cut region; filling the T-shaped cavity with a gap fill dielectric; removing the hardmask; and recessing the metal lines, wherein the gap fill dielectric overhangs portions of the select metal line that, by the recessing, form the self-aligned vias at ends of the metal lines. A structure is also provided.
    Type: Application
    Filed: October 26, 2019
    Publication date: April 29, 2021
    Inventors: Ashim Dutta, John Arnold, Dominik Metzler
  • Publication number: 20210126051
    Abstract: Techniques for preserving the underlying dielectric layer during MRAM device formation are provided. In one aspect, a method of forming an MRAM device includes: depositing a first dielectric cap layer onto a substrate over logic and memory areas of the substrate; depositing a sacrificial metal layer onto the first dielectric cap layer; patterning the sacrificial metal layer, wherein the patterned sacrificial metal layer is present over the first dielectric cap layer in at least the logic area; depositing a second dielectric cap layer onto the first dielectric cap layer; forming an MRAM stack on the second dielectric cap layer; patterning the MRAM stack using ion beam etching into at least one memory cell, wherein the patterned sacrificial metal layer protects the first dielectric cap layer in the logic area; and removing the patterned sacrificial metal layer. An MRAM device is also provided.
    Type: Application
    Filed: October 24, 2019
    Publication date: April 29, 2021
    Inventors: Ashim Dutta, Michael Rizzolo
  • Publication number: 20210104432
    Abstract: A method of forming a semiconductor structure includes forming one or more interconnect lines, the one or more interconnect lines including trenches of a first metal material surrounded by a first interlayer dielectric layer. The method also includes forming pillars of a second metal material different than the first metal material over the one or more interconnect lines utilizing a metal on metal growth process, and forming an etch stop dielectric layer, the pillars of the second metal material shaping the etch stop dielectric layer. The method further includes forming one or more vias to the one or more interconnect lines, the one or more vias being fully aligned to the one or more interconnect lines using the etch stop dielectric layer.
    Type: Application
    Filed: October 4, 2019
    Publication date: April 8, 2021
    Inventors: Ekmini Anuja De Silva, Ashim Dutta, Praveen Joseph, Nelson Felix
  • Publication number: 20210104660
    Abstract: Provided are embodiments for a semiconductor device that includes a bottom contact; a multi-layer bottom electrode formed over the bottom contact; a magnetic tunnel junction stack formed over the multi-layer bottom electrode; and a top electrode formed over the magnetic tunnel junction stack. Also provided are embodiments for forming the semiconductor device described herein.
    Type: Application
    Filed: October 8, 2019
    Publication date: April 8, 2021
    Inventors: Ashim Dutta, Ekmini Anuja De Silva
  • Publication number: 20210090951
    Abstract: A method for fabricating a semiconductor device includes recessing a first odd hardmask and a first even hardmask to form recessed odd and even hardmasks, forming a first conductive hardmask including first conductive hardmask material on the recessed odd hardmask and a second conductive hardmask on the recessed even hardmask, and forming self-aligned vias at line ends corresponding to the first odd and even conductive lines based at least in part on the first and second conductive hardmasks.
    Type: Application
    Filed: September 24, 2019
    Publication date: March 25, 2021
    Inventors: John C. Arnold, Ashim Dutta, Dominik Metzler, Ekmini A. De Silva
  • Publication number: 20210091306
    Abstract: Controlled IBE techniques for MRAM stack patterning are provided. In one aspect, a method of forming an MRAM device includes: patterning an MRAM stack disposed on a dielectric into individual memory cells using IBE landing on the dielectric while dynamically adjusting an etch time to compensate for variations in a thickness of the MRAM stack, wherein each of the memory cells includes a bottom electrode, an MTJ, and a top electrode; removing foot flares from the bottom electrode of the memory cells which are created during the patterning of the MRAM stack; removing residue from sidewalls of the memory cells which includes metal redeposited during the patterning of the MRAM stack and during the removing of the foot flares; and covering the memory cells in a dielectric encapsulant. An MRAM device is also provided.
    Type: Application
    Filed: September 25, 2019
    Publication date: March 25, 2021
    Inventors: Ashim Dutta, Chih-Chao Yang, Lijuan Zou, John Arnold
  • Publication number: 20210091301
    Abstract: Methods for forming an integrated circuit are provided. Aspects include providing a wafer substrate having an embedded memory area interconnect structure and an embedded non-memory area interconnect structure, the memory area interconnect structure comprising metal interconnects formed within a first interlayer dielectric, recessing a portion of the memory area interconnect structure, forming a bottom electrode contact on the recessed portion of the memory area interconnect structure, forming a bottom electrode over the bottom electrode contact, forming a protective dielectric layer over the non-memory area interconnect structure, and forming memory element stack layers on a portion of the bottom electrode.
    Type: Application
    Filed: September 23, 2019
    Publication date: March 25, 2021
    Inventors: John Arnold, Dominik Metzler, Ashim Dutta, Donald Canaperi
  • Patent number: 10957850
    Abstract: A method for fabricating a semiconductor device includes forming a first encapsulation layer along the device, including forming the first encapsulation layer along a memory device region associated with a memory device, forming an intermediate layer on the first encapsulation layer to enable etch endpoint detection and endpoint-based process control for encapsulation layer etch back, and forming a second encapsulation layer on the intermediate layer.
    Type: Grant
    Filed: October 4, 2018
    Date of Patent: March 23, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ashim Dutta, Isabel Cristina Chu, Son Nguyen, Michael Rizzolo, John C. Arnold
  • Publication number: 20210082807
    Abstract: Embodiments of the present invention are directed to fabrication method and resulting structures for placing self-aligned top vias at line ends of an interconnect structure. In a non-limiting embodiment of the invention, a line feature is formed in a metallization layer of an interconnect structure. The line feature can include a line hard mask. A trench is formed in the line feature to expose line ends of the line feature. The trench is filled with a host material and a growth inhibitor is formed over a first line end of the line feature. A via mask is formed over a second line end of the line feature. The via mask can be selectively grown on an exposed surface of the host material. Portions of the line feature that are not covered by the via mask are recessed to define a self-aligned top via at the second line end.
    Type: Application
    Filed: September 18, 2019
    Publication date: March 18, 2021
    Inventors: Ashim DUTTA, Ekmini Anuja De Silva, Dominik METZLER, John Arnold
  • Publication number: 20210082746
    Abstract: Methods and structures for forming vias are provided. The method includes forming a structure that includes an odd line hardmask and an even line hardmask. The odd line hardmask and the even line hardmask include different hardmask materials that have different etch selectivity with respect to each other. The method includes patterning vias separately into the odd line hardmask and the even line hardmask based on the different etch selectivity of the different hardmask materials. The method also includes forming via plugs at the vias. The method includes cutting even line cuts and odd line cuts into the structure. The even line cuts and the odd line cuts are self-aligned with the vias. The vias are formed at line ends of the structure.
    Type: Application
    Filed: September 13, 2019
    Publication date: March 18, 2021
    Inventors: John C. Arnold, Ashim Dutta, Dominik Metzler, Timothy M. Philip, Sagarika Mukesh
  • Publication number: 20210013400
    Abstract: A method of forming a semiconductor structure includes forming a dielectric layer surrounding contacts over a top surface and bevel edge of a substrate, forming a sacrificial buffer layer over the dielectric layer, removing portions of the sacrificial buffer layer formed over the dielectric layer on the top surface of the substrate, and patterning device structures including one or more metal layers over the contacts, wherein patterning the device structures removes portions of the metal layers formed over the top surface of the substrate leaving the metal layers on the bevel edge. The method also includes forming an encapsulation layer and performing a bevel dry etch to remove the encapsulation layer and the metal layers on the bevel edge. The bevel dry etch damages the sacrificial buffer layer on the bevel edge underneath the metal layers. The method further includes removing the damaged sacrificial buffer layer from the bevel edge.
    Type: Application
    Filed: July 9, 2019
    Publication date: January 14, 2021
    Inventors: Ashim Dutta, Saba Zare, Michael Rizzolo, Theodorus E. Standaert, Daniel Charles Edelstein
  • Patent number: 10892404
    Abstract: A method of forming a semiconductor structure includes forming a dielectric layer surrounding contacts over a top surface and bevel edge of a substrate, forming a sacrificial buffer layer over the dielectric layer, removing portions of the sacrificial buffer layer formed over the dielectric layer on the top surface of the substrate, and patterning device structures including one or more metal layers over the contacts, wherein patterning the device structures removes portions of the metal layers formed over the top surface of the substrate leaving the metal layers on the bevel edge. The method also includes forming an encapsulation layer and performing a bevel dry etch to remove the encapsulation layer and the metal layers on the bevel edge. The bevel dry etch damages the sacrificial buffer layer on the bevel edge underneath the metal layers. The method further includes removing the damaged sacrificial buffer layer from the bevel edge.
    Type: Grant
    Filed: July 9, 2019
    Date of Patent: January 12, 2021
    Assignee: International Business Machines Corporation
    Inventors: Ashim Dutta, Saba Zare, Michael Rizzolo, Theodorus E. Standaert, Daniel Charles Edelstein
  • Patent number: 10886462
    Abstract: A method for selectively encapsulating embedded memory pillars in a semiconductor device includes coating a passivation layer on a first dielectric surface on a first outer dielectric layer present in the semiconductor device. The passivation layer adheres to the dielectric surface selective to metal. The method includes depositing an encapsulation layer on side and top surfaces of the embedded memory pillars. The passivation layer prevents deposition of the encapsulation layer on the first dielectric surface of the first outer layer dielectric. The method includes removing the first outer dielectric layer from horizontal subraces around the embedded memory pillar and the encapsulation layer from the top surface of the embedded memory pillars.
    Type: Grant
    Filed: November 19, 2018
    Date of Patent: January 5, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ashim Dutta, Ekmini Anuja de Silva, Jennifer Church, Luciana Meli Thompson
  • Patent number: 10879107
    Abstract: A method includes forming a first insulating layer having one or more vias formed in at least a portion of the first insulating layer. The vias are filled with a first metallic material. A cap layer is deposited on a top surface of the first insulating layer and a top surface of the one or more vias and a second insulating layer is deposited on a top surface of the cap layer. One or more openings are formed in the second insulating layer and the cap layer. A self-assembled monolayer is formed on an exposed top surface of the first metallic material in the one or more vias. A barrier layer is formed on at least the exposed surface of the one or more openings. The self-assembled monolayer is removed and the one or more openings are filled with a second metallic material.
    Type: Grant
    Filed: November 5, 2018
    Date of Patent: December 29, 2020
    Assignee: International Business Machines Corporation
    Inventors: Ashim Dutta, Ekmini Anuja De Silva, Jennifer Church, Luciana Meli Thompson
  • Publication number: 20200403032
    Abstract: A method is presented for preventing excessive cap dielectric loss in memory areas and logic areas of a device. The method includes forming a first conductive line with top via and a conductive pad over a dielectric layer, wherein the conductive pad includes a microstud, depositing a dielectric cap in direct contact with the first conductive line and the conductive pad, and constructing a top electrode, a magnetic tunnel junction (MTJ) stack, and a bottom electrode in vertical alignment with the microstud of the conductive pad.
    Type: Application
    Filed: June 18, 2019
    Publication date: December 24, 2020
    Inventors: Ashim Dutta, Chih-Chao Yang, Ekmini A. De Silva, Dominik Metzler
  • Publication number: 20200357748
    Abstract: An interconnect structure is provided. The interconnect structure includes first conducting lines and second conducting lines. The first conducting lines are formed of a first metallic material and include at least one individual first conducting line in contact with a first corresponding substrate conducting line. The second conducting lines are formed of a second metallic material and include at least one individual second conducting line between neighboring first conducting lines and in contact with a second corresponding substrate conducting line. The at least one individual second conducting line is separated from each of the neighboring first conducting lines by controlled distances.
    Type: Application
    Filed: May 10, 2019
    Publication date: November 12, 2020
    Inventors: Ashim DUTTA, Ekmini Anuja De Silva
  • Patent number: 10833258
    Abstract: MRAM devices with in-situ encapsulation are provided. In one aspect, a method of forming an MRAM device includes: patterning an MRAM stack disposed on a dielectric into individual memory cell stacks, wherein the MRAM stack includes a bottom electrode, a MTJ, and a top electrode, and wherein the patterning is performed using an intermediate angle IBE landing on the dielectric; removing redeposited metal from the memory cell stacks using a high angle IBE; redepositing the dielectric along the sidewalls of the memory cell stacks using a low angle IBE to form a first layer of dielectric encapsulating the memory cell stacks; and depositing a second layer of dielectric, wherein the first/second layers of dielectric form a bilayer dielectric spacer structure, wherein the patterning, removing of the redeposited metal, and redepositing the dielectric steps are all performed in-situ. An MRAM device is also provided.
    Type: Grant
    Filed: May 2, 2019
    Date of Patent: November 10, 2020
    Assignee: International Business Machines Corporation
    Inventors: Ashim Dutta, Chih-Chao Yang, Daniel C. Edelstein, Karthik Yogendra, John C. Arnold
  • Patent number: 10833257
    Abstract: Techniques are provided for fabricating semiconductor integrated circuit devices with embedded magnetic random-access memory (MRAM) devices. For example, a MRAM device and a multi-level bottom electrode via contact are formed within a back-end-of line layer. The MRAM device includes a memory device pillar having a bottom electrode, a magnetic tunnel junction structure, and an upper electrode. The multi-level bottom electrode via contact is disposed below and in contact with the bottom electrode. The multi-level bottom electrode via contact includes a first via contact disposed in a first insulation layer, and a second via contact disposed in a second insulation layer. The first and second insulation layers allow for sacrificial etching of the first and second insulation layers during formation of the MRAM device while retaining a sufficient thickness of remaining insulation material to serve as a capping layer to protect metallic wiring that is disposed in an underlying metallization layer.
    Type: Grant
    Filed: May 2, 2019
    Date of Patent: November 10, 2020
    Assignee: International Business Machines Corporation
    Inventors: Ashim Dutta, John C. Arnold, Chih-Chao Yang, Theodorus E. Standaert