Patents by Inventor Rajiv Yadav Ranjan

Rajiv Yadav Ranjan 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: 20130119498
    Abstract: A spin-torque transfer magnetic random access memory (STTMRAM) element employed to store a state based on the magnetic orientation of a free layer, the STTMRAM element is made of a first perpendicular free layer (PFL) including a first perpendicular enhancement layer (PEL). The first PFL is formed on top of a seed layer. The STTMRAM element further includes a barrier layer formed on top of the first PFL and a second perpendicular reference layer (PRL) that has a second PEL, the second PRL is formed on top of the barrier layer. The STTMRAM element further includes a capping layer that is formed on top of the second PRL.
    Type: Application
    Filed: January 9, 2013
    Publication date: May 16, 2013
    Applicant: Avalanche Technology, Inc.
    Inventors: Yiming Huai, Yuchen Zhou, Jing Zhang, Roger Klas Malmhall, Ioan Tudosa, Rajiv Yadav Ranjan
  • Patent number: 8440471
    Abstract: A method of flash-RAM memory includes non-volatile random access memory (RAM) formed on a monolithic die and non-volatile page-mode memory formed on top of the non-volatile RAM, the non-volatile page-mode memory and the non-volatile RAM reside on the monolithic die. The non-volatile RAM is formed of stacks of magnetic memory cells arranged in three-dimensional form for higher density and lower costs.
    Type: Grant
    Filed: January 6, 2012
    Date of Patent: May 14, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Mahmud Assar
  • Patent number: 8427863
    Abstract: A multi-state low-current-switching magnetic memory element (magnetic memory element) comprising a free layer, two stacks, and a magnetic tunneling junction is disclosed. The stacks and magnetic tunneling junction are disposed upon surfaces of the free layer, with the magnetic tunneling junction located between the stacks. The stacks pin magnetic domains within the free layer, creating a free layer domain wall. A current passed from stack to stack pushes the domain wall, repositioning the domain wall within the free layer. The position of the domain wall relative to the magnetic tunnel junction corresponds to a unique resistance value, and passing current from a stack to the magnetic tunnel junction reads the magnetic memory element's resistance. Thus, unique memory states may be achieved by moving the domain wall.
    Type: Grant
    Filed: January 7, 2011
    Date of Patent: April 23, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Roger Klaus Malmhall, Parviz Keshtbod
  • Patent number: 8422286
    Abstract: A spin-torque transfer memory random access memory (STTMRAM) element is disclosed and has a fixed layer, a barrier layer formed upon the fixed layer, and a free layer comprised of a low-crystallization temperature alloy of CoFeB—Z where Z is below 25 atomic percent of one or more of titanium, (Ti), yittrium (Y), zirconium (Zr), and vanadium (V), wherein during a write operation, a bidirectional electric current is applied across the STTMRAM element to switch the magnetization of the free layer between parallel and anti-parallel states relative to the magnetization of the fixed layer.
    Type: Grant
    Filed: April 2, 2012
    Date of Patent: April 16, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Roger Klas Malmhall
  • Publication number: 20130087870
    Abstract: A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
    Type: Application
    Filed: May 21, 2012
    Publication date: April 11, 2013
    Applicant: AVALANCHE TECHNOLOGY, INC.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Roger Klas Malmhall
  • Publication number: 20130087872
    Abstract: A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
    Type: Application
    Filed: May 21, 2012
    Publication date: April 11, 2013
    Applicant: AVALANCHE TECHNOLOGY, INC.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Roger Klas Malmhall
  • Publication number: 20130088914
    Abstract: A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
    Type: Application
    Filed: May 18, 2012
    Publication date: April 11, 2013
    Applicant: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Roger Klas Malmhall
  • Publication number: 20130087869
    Abstract: A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
    Type: Application
    Filed: May 18, 2012
    Publication date: April 11, 2013
    Applicant: AVALANCHE TECHNOLOGY, INC.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Roger Klas Malmhall
  • Publication number: 20130088915
    Abstract: A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
    Type: Application
    Filed: May 18, 2012
    Publication date: April 11, 2013
    Applicant: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Roger Klas Malmhall
  • Publication number: 20130087871
    Abstract: A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
    Type: Application
    Filed: May 21, 2012
    Publication date: April 11, 2013
    Applicant: AVALANCHE TECHNOLOGY, INC.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Roger Klas Malmhall
  • Patent number: 8405174
    Abstract: A non-volatile current-switching magnetic memory element includes a bottom electrode, a pinning layer formed on top of the bottom electrode, and a fixed layer formed on top of the pinning layer. The memory element further includes a tunnel layer formed on top of the pinning layer, a first free layer formed on top of the tunnel layer, a granular film layer formed on top of the free layer, a second free layer formed on top of the granular film layer, a cap layer formed on top of the second layer and a top electrode formed on top of the cap layer.
    Type: Grant
    Filed: April 23, 2012
    Date of Patent: March 26, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod
  • Patent number: 8399942
    Abstract: A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
    Type: Grant
    Filed: October 5, 2011
    Date of Patent: March 19, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Roger Klas Malmhall
  • Patent number: 8399943
    Abstract: A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
    Type: Grant
    Filed: October 5, 2011
    Date of Patent: March 19, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Roger Klas Malmhall
  • Patent number: 8391058
    Abstract: A flash-RAM memory includes non-volatile random access memory (RAM) formed on a monolithic die and non-volatile page-mode memory formed on top of the non-volatile RAM, the non-volatile page-mode memory and the non-volatile RAM reside on the monolithic die. The non-volatile RAM is formed of stacks of magnetic memory cells arranged in three-dimensional form for higher density and lower costs.
    Type: Grant
    Filed: January 6, 2012
    Date of Patent: March 5, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Mahmud Assar
  • Patent number: 8389301
    Abstract: A non-uniform switching based non-volatile magnetic memory element includes a fixed layer, a barrier layer formed on top of the fixed layer, a first free layer formed on top of the barrier layer, a non-uniform switching layer (NSL) formed on top of the first free layer, and a second free layer formed on top of the non-uniform switching layer. Switching current is applied, in a direction that is substantially perpendicular to the fixed layer, barrier layer, first free layer, non-uniform switching layer and the second free layer causing switching between states of the first free layer, second free layer and non-uniform switching layer with substantially reduced switching current.
    Type: Grant
    Filed: November 28, 2011
    Date of Patent: March 5, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Petro Estakhri, Mahmud Assar, Parviz Keshtbod
  • Patent number: 8391054
    Abstract: A multi-state current-switching magnetic memory element includes a stack of magnetic tunneling junction (MTJ) separated by a non-magnetic layer for storing more than one bit of information, wherein different levels of current applied to the memory element cause switching to different states.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: March 5, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Mahmud Assar, Parviz Keshtbod
  • Publication number: 20130052752
    Abstract: Various embodiments of the invention relate to etching processes used in fabrication of MTJ cells in an MRAM device. The various embodiments can be used in combination with each other. The first embodiment adds a hard mask buffer layer between a hard mask and a top electrode. The second embodiment uses a multilayered etching hard mask. The third embodiment uses a multilayered top electrode structure including a first Cu layer under a second layer such as Ta. The fourth embodiment is a two-phase etching process used for the bottom electrode to remove re-deposited material while maintaining a more vertical sidewall etching profile. In the first phase the bottom electrode layer is removed using carbonaceous reactive ion etching until the endpoint. In the second phase an inert gas and/or oxygen plasma is used to remove the polymer that was deposited during the previous etching processes.
    Type: Application
    Filed: August 30, 2011
    Publication date: February 28, 2013
    Inventors: Kimihiro Satoh, Yiming Huai, Jing Zhang, Rajiv Yadav Ranjan, Parviz Keshtbod, Roger K. Malmhall
  • Patent number: 8374025
    Abstract: A spin-torque transfer memory random access memory (STTMRAM) element includes a fixed layer having a magnetization that is substantially fixed in one direction and a barrier layer formed on top of the fixed layer and a free layer. The free layer has a number of alternating laminates, each laminate being made of a magnetic layer and an insulating layer. The magnetic layer is switchable and formed on top of the barrier layer. The free layer is capable of switching its magnetization to a parallel or an anti-parallel state relative to the magnetization of the fixed layer during a write operation when bidirectional electric current is applied across the STTMRAM element. Magnetic layers of the laminates are ferromagnetically coupled to switch together as a single domain during the write operation and the magnetization of the fixed and free layers and the magnetic layers of the laminates have either in-plane or perpendicular anisotropy.
    Type: Grant
    Filed: May 13, 2010
    Date of Patent: February 12, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Roger Klas Malmhall
  • Publication number: 20130001717
    Abstract: Thin film perpendicular magnetic multilayer structures which can be used in various thin film magnetic structures are described. One multilayer structure embodiment is formed by interlacing a soft magnetic layer and a FePt based magnetic layer in N repeats, where N is a positive integer. Various MRAM MTJ structures are described using multilayer structure embodiments for a free layer, a reference layer, and a pinned layer according to the invention.
    Type: Application
    Filed: June 29, 2012
    Publication date: January 3, 2013
    Inventors: Yuchen Zhou, Yiming Huai, Rajiv Yadav Ranjan, Jing Zhang, Roger Klas Malmhall
  • Publication number: 20120326712
    Abstract: High-frequency resonance method is used to measure magnetic parameters of magnetic thin film stacks that show magnetoresistance including MTJs and giant magnetoresistance spin valves. The thin film sample can be unpatterned. Probe tips are electrically connected to the surface of the film (or alternatively one probe tip can be punched into the thin film stack) and voltage measurements are taken while injecting high frequency oscillating current between them to cause a change in electrical resistance when one of the layers in the magnetic film stack changes direction. A measured resonance curve can be determined from voltages at different current frequencies. The damping, related to the width of the resonance curve peak, is determined through curve fitting. In embodiments of the invention a variable magnetic field is also applied to vary the resonance frequency and extract the magnetic anisotropy and/or magnetic saturation of the magnetic layers.
    Type: Application
    Filed: June 21, 2011
    Publication date: December 27, 2012
    Inventors: Ioan Tudosa, Yuchen Zhou, Jing Zhang, Rajiv Yadav Ranjan, Yiming Huai