Patents by Inventor D. V. Nirmal Ramaswamy

D. V. Nirmal Ramaswamy 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: 9240548
    Abstract: A method of forming an array of memory cells includes forming lines of covering material that are elevationally over and along lines of spaced sense line contacts. Longitudinal orientation of the lines of covering material is used in forming lines comprising programmable material and outer electrode material that are between and along the lines of covering material. The covering material is removed over the spaced sense line contacts and the spaced sense line contacts are exposed. Access lines are formed. Sense lines are formed that are electrically coupled to the spaced sense line contacts. The sense lines are angled relative to the lines of spaced sense line contacts and relative to the access lines. Other embodiments, including structure independent of method, are disclosed.
    Type: Grant
    Filed: May 31, 2012
    Date of Patent: January 19, 2016
    Assignee: Micron Technology, Inc.
    Inventors: Scott E. Sills, D. V. Nirmal Ramaswamy
  • Patent number: 9240495
    Abstract: A memory cell is provided including a tunnel dielectric layer overlying a semiconductor substrate. The memory cell also includes a floating gate having a first portion overlying the tunnel dielectric layer and a second portion in the form of a nanorod extending from the first portion. In addition, a control gate layer is separated from the floating gate by an intergate dielectric layer.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: January 19, 2016
    Assignee: Micron Technology, Inc.
    Inventors: Gurtej S. Sandhu, D. V. Nirmal Ramaswamy
  • Patent number: 9230978
    Abstract: Some embodiments include methods of forming semiconductor constructions. Alternating layers of n-type doped material and p-type doped material may be formed. The alternating layers may be patterned into a plurality of vertical columns that are spaced from one another by openings. The openings may be lined with tunnel dielectric, charge-storage material and blocking dielectric. Alternating layers of insulative material and conductive control gate material may be formed within the lined openings. Some embodiments include methods of forming NAND unit cells. Columns of alternating n-type material and p-type material may be formed. The columns may be lined with a layer of tunnel dielectric, a layer of charge-storage material, and a layer of blocking dielectric. Alternating layers of insulative material and conductive control gate material may be formed between the lined columns. Some embodiments include semiconductor constructions, and some embodiments include NAND unit cells.
    Type: Grant
    Filed: December 12, 2013
    Date of Patent: January 5, 2016
    Assignee: Micron Technology, Inc.
    Inventors: D. V. Nirmal Ramaswamy, Gurtej S. Sandhu
  • Patent number: 9231206
    Abstract: A method of forming a ferroelectric memory cell. The method comprises forming an electrode material exhibiting a desired dominant crystallographic orientation. A hafnium-based material is formed over the electrode material and the hafnium-based material is crystallized to induce formation of a ferroelectric material having a desired crystallographic orientation. Additional methods are also described, as are semiconductor device structures including the ferroelectric material.
    Type: Grant
    Filed: September 13, 2013
    Date of Patent: January 5, 2016
    Assignee: Micron Technology, Inc.
    Inventors: Qian Tao, Matthew N. Rocklein, Beth R. Cook, D. V. Nirmal Ramaswamy
  • Patent number: 9230685
    Abstract: Memory programming methods and memory systems are described. One example memory programming method includes first applying a first signal to a memory cell to attempt to program the memory cell to a desired state, wherein the first signal corresponds to the desired state, after the first applying, determining that the memory cell failed to place in the desired state, after the determining, second applying a second signal to the memory cell, wherein the second signal corresponds to another state which is different than the desired state, and after the second applying, third applying a third signal to the memory cell to program the memory cell to the desired state, wherein the third signal corresponds to the desired state. Additional method and apparatus are described.
    Type: Grant
    Filed: October 23, 2012
    Date of Patent: January 5, 2016
    Assignee: Micron Technology, Inc.
    Inventors: Jonathan Strand, Adam Johnson, Xiaonan Chen, D. V. Nirmal Ramaswamy
  • Publication number: 20150380432
    Abstract: A charge-retaining transistor includes a control gate and an inter-gate dielectric alongside the control gate. A charge-storage node of the transistor includes first semiconductor material alongside the inter-gate dielectric. Islands of charge-trapping material are alongside the first semiconductor material. An oxidation-protective material is alongside the islands. Second semiconductor material is alongside the oxidation-protective material, and is of some different composition from that of the oxidation-protective material. Tunnel dielectric is alongside the charge-storage node. Channel material is alongside the tunnel dielectric. Additional embodiments, including methods, are disclosed.
    Type: Application
    Filed: September 8, 2015
    Publication date: December 31, 2015
    Inventor: D.V. Nirmal Ramaswamy
  • Publication number: 20150380646
    Abstract: Semiconductor memory devices, resistive memory devices, memory cell structures, and methods of forming a resistive memory cell are provided. One example method of a resistive memory cell can include a number of dielectric regions formed between two electrodes, and a barrier dielectric region formed between each of the dielectric regions. The barrier dielectric region serves to reduce an oxygen diffusion rate associated with the dielectric regions.
    Type: Application
    Filed: September 10, 2015
    Publication date: December 31, 2015
    Inventors: Matthew N. Rocklein, D.V. Nirmal Ramaswamy
  • Patent number: 9219225
    Abstract: Multi-bit ferroelectric memory devices and methods of forming the same are provided. One example method of forming a multi-bit ferroelectric memory device can include forming a first ferroelectric material on a first side of a via, removing a material to expose a second side of the via, and forming second ferroelectric material on the second side of the via at a different thickness compared to the first side of the via.
    Type: Grant
    Filed: October 31, 2013
    Date of Patent: December 22, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Kamal M Karda, F Daniel Gealy, D. V. Nirmal Ramaswamy, Chandra V Mouli
  • Publication number: 20150364683
    Abstract: Memory cells with recessed electrode contacts and methods of forming the same are provided. An example memory cell can include an electrode contact formed in a substrate. An upper surface of the electrode contact is recessed a distance relative to an upper surface of the substrate. A first portion of a memory element is formed on an upper surface of the electrode contact and the upper surface of the substrate.
    Type: Application
    Filed: August 24, 2015
    Publication date: December 17, 2015
    Inventors: Scott E. Sills, D.V. Nirmal Ramaswamy
  • Patent number: 9196753
    Abstract: Methods, devices, and systems are provided for a select device that can include a semiconductive stack of at least one semiconductive material formed on a first electrode, where the semiconductive stack can have a thickness of about 700 angstroms (?) or less. Each of the at least one semiconductive material can have an associated band gap of about 4 electron volts (eV) or less and a second electrode can be formed on the semiconductive stack.
    Type: Grant
    Filed: April 19, 2011
    Date of Patent: November 24, 2015
    Assignee: Micron Technology, Inc.
    Inventors: D. V. Nirmal Ramaswamy, Gurtej Sandhu
  • Publication number: 20150333257
    Abstract: A method of forming a resistive memory element comprises forming an oxide material over a first electrode. The oxide material is exposed to a plasma process to form a treated oxide material. A second electrode is formed on the treated oxide material. Additional methods of forming a resistive memory element, as well as related resistive memory elements, resistive memory cells, and resistive memory devices are also described.
    Type: Application
    Filed: July 22, 2015
    Publication date: November 19, 2015
    Inventors: D.V. Nirmal Ramaswamy, Sanh D. Tang, Alessandro Torsi, Muralikrishnan Balakrishnan, Xiaonan Chen, John K. Zahurak
  • Publication number: 20150311217
    Abstract: Ferroelectric memory and methods of forming the same are provided. An example memory cell can include a buried recessed access device (BRAD) formed in a substrate and a ferroelectric capacitor formed on the BRAD.
    Type: Application
    Filed: April 28, 2014
    Publication date: October 29, 2015
    Applicant: Micron Technology, Inc.
    Inventors: Ashonita A. Chavan, Alessandro Calderoni, D.V. Nirmal Ramaswamy
  • Patent number: 9159845
    Abstract: A charge-retaining transistor includes a control gate and an inter-gate dielectric alongside the control gate. A charge-storage node of the transistor includes first semiconductor material alongside the inter-gate dielectric. Islands of charge-trapping material are alongside the first semiconductor material. An oxidation-protective material is alongside the islands. Second semiconductor material is alongside the oxidation-protective material, and is of some different composition from that of the oxidation-protective material. Tunnel dielectric is alongside the charge-storage node. Channel material is alongside the tunnel dielectric. Additional embodiments, including methods, are disclosed.
    Type: Grant
    Filed: May 15, 2013
    Date of Patent: October 13, 2015
    Assignee: Micron Technology, Inc.
    Inventor: D. V. Nirmal Ramaswamy
  • Patent number: 9159921
    Abstract: Semiconductor memory devices, resistive memory devices, memory cell structures, and methods of forming a resistive memory cell are provided. One example method of a resistive memory cell can include a number of dielectric regions formed between two electrodes, and a barrier dielectric region formed between each of the dielectric regions. The barrier dielectric region serves to reduce an oxygen diffusion rate associated with the dielectric regions.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: October 13, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Matthew N. Rocklein, D. V. Nirmal Ramaswamy
  • Patent number: 9153776
    Abstract: Some embodiments include a memory cell having an electrode and a switching material over the electrode. The electrode is a first composition which includes a first metal and a second metal. The switching material is a second composition which includes the second metal. The second composition is directly against the first composition. Some embodiments include methods of forming memory cells.
    Type: Grant
    Filed: November 1, 2013
    Date of Patent: October 6, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Martin Schubert, Scott E. Sills, D. V. Nirmal Ramaswamy
  • Patent number: 9147839
    Abstract: Memory cells with recessed electrode contacts and methods of forming the same are provided. An example memory cell can include an electrode contact formed in a substrate. An upper surface of the electrode contact is recessed a distance relative to an upper surface of the substrate. A first portion of a memory element is formed on an upper surface of the electrode contact and the upper surface of the substrate.
    Type: Grant
    Filed: September 5, 2013
    Date of Patent: September 29, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Scott E. Sills, D. V. Nirmal Ramaswamy
  • Patent number: 9142767
    Abstract: Resistive memory cells including an integrated select device and storage element and methods of forming the same are described herein. As an example, a resistive memory cell can include a select device structure including a Schottky interface, and a storage element integrated with the select device structure such that an electrode corresponding to the Schottky interface serves as a first electrode of the storage element. The storage element can include a storage material formed between the first electrode and a second electrode.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: September 22, 2015
    Assignee: Micron Technology, Inc.
    Inventors: David H. Wells, D. V. Nirmal Ramaswamy, Kirk D. Prall
  • Patent number: 9136306
    Abstract: Some embodiments include memory structures having a diode over a memory cell. The memory cell can include programmable material between a pair of electrodes, with the programmable material containing a multivalent metal oxide directly against a high-k dielectric. The diode can include a first diode electrode directly over one of the memory cell electrodes and electrically coupled with the memory cell electrode, and can include a second diode electrode laterally outward of the first diode electrode and not directly over the memory cell. Some embodiments include memory arrays comprising the memory structures, and some embodiments include methods of making the memory structures.
    Type: Grant
    Filed: December 29, 2011
    Date of Patent: September 15, 2015
    Assignee: Micron Technology, Inc.
    Inventors: D. V. Nirmal Ramaswamy, Mark S. Korber
  • Publication number: 20150255153
    Abstract: The present disclosure includes apparatuses and methods for sensing a resistive memory cell. A number of embodiments include performing a sensing operation on a memory cell to determine a current value associated with the memory cell, applying a programming signal to the memory cell, and determining a data state of the memory cell based on the current value associated with the memory cell before applying the programming signal and a current value associated with the memory cell after applying the programming signal.
    Type: Application
    Filed: May 21, 2015
    Publication date: September 10, 2015
    Inventors: D.V. Nirmal Ramaswamy, Gurtej S. Sandhu, Lei Bi, Adam D. Johnson, Brent Keeth, Alessandro Calderoni, Scott E. Sills
  • Patent number: 9117998
    Abstract: A method of forming a nonvolatile memory cell includes forming a first electrode having a first current conductive material and a circumferentially self-aligned second current conductive material projecting elevationally outward from the first current conductive material. The second current conductive material is different in composition from the first current conductive material. A programmable region is formed over the first current conductive material and over the projecting second current conductive material of the first electrode. A second electrode is formed over the programmable region. In one embodiment, the programmable region is ion conductive material, and at least one of the first and second electrodes has an electrochemically active surface directly against the ion conductive material. Other method and structural aspects are disclosed.
    Type: Grant
    Filed: June 30, 2014
    Date of Patent: August 25, 2015
    Assignee: Micron Technology, Inc.
    Inventors: D. V. Nirmal Ramaswamy, Gurtej S. Sandhu