Patents Assigned to Crossbar, Inc.
  • Patent number: 9047939
    Abstract: A non-volatile memory device includes an array of memory units, each having resistive memory cells and a local word line. Each memory cell has a first and a second end, the second ends are coupled to the local word line of the corresponding memory unit. Bit lines are provided, each coupled to the first end of each resistive memory cell. A plurality of select transistors is provided, each associated with one memory unit and having a drain terminal coupled to the local word line of the associated memory unit. First and second global word lines are provided, each coupled to a control terminal of at least one select transistor. First and second source lines are provided, each coupled to a source terminal of at least one select transistor. The memory device is configured to concurrently read out all resistive memory cells in one selected memory unit in a read operation.
    Type: Grant
    Filed: January 28, 2014
    Date of Patent: June 2, 2015
    Assignee: Crossbar, Inc.
    Inventors: Harry Kuo, Hagop Nazarian
  • Patent number: 9036400
    Abstract: The present invention relates to integrating a resistive memory device on top of an IC substrate monolithically using IC-foundry compatible processes.
    Type: Grant
    Filed: November 5, 2013
    Date of Patent: May 19, 2015
    Assignee: Crossbar, Inc.
    Inventor: Wei Lu
  • Patent number: 9035276
    Abstract: A memory device includes a first plurality of memory cells arranged in a first crossbar array, a first thickness of dielectric material overlying the first plurality of memory cells, and a second plurality of memory cells arranged in a second crossbar array overlying the first thickness of dielectric material. The memory device further includes a second thickness of dielectric material overlying the second plurality of memory cells. In a specific embodiment, the memory device further includes a Nth thickness of dielectric material overlying an Nth plurality of memory cells, where N is an integer ranging from 3 to 8.
    Type: Grant
    Filed: February 7, 2014
    Date of Patent: May 19, 2015
    Assignee: Crossbar, Inc.
    Inventor: Scott Brad Herner
  • Publication number: 20150129829
    Abstract: Providing for one time programmable, multi-level cell two-terminal memory is described herein. In some embodiments, the one time programmable, multi-level cell memory can have a 1 diode 1 resistor configuration, per memory cell. A memory cell according to one or more disclosed embodiments can be programmed to one of a set of multiple logical bits, and can be configured to mitigate or avoid erasure. Accordingly, the memory cell can be employed as a single program, non-erasable memory. Expressed differently, the memory cell can be referred to as a write once read many (WORM) category of memory.
    Type: Application
    Filed: November 13, 2013
    Publication date: May 14, 2015
    Applicant: Crossbar, Inc.
    Inventor: Tanmay KUMAR
  • Patent number: 9012307
    Abstract: A method of forming a two terminal device. The method includes forming a first dielectric material overlying a surface region of a substrate. A bottom wiring material is formed overlying the first dielectric material and a switching material is deposited overlying the bottom wiring material. The bottom wiring material and the switching material is subjected to a first patterning and etching process to form a first structure having a top surface region and a side region. The first structure includes at least a bottom wiring structure and a switching element having a first side region, and a top surface region including an exposed region of the switching element. A second dielectric material is formed overlying at least the first structure including the exposed region of the switching element. The method forms an opening region in a portion of the second dielectric layer to expose a portion of the top surface region of the switching element.
    Type: Grant
    Filed: July 13, 2010
    Date of Patent: April 21, 2015
    Assignee: Crossbar, Inc.
    Inventors: Sung Hyun Jo, Scott Brad Herner
  • Patent number: 9013911
    Abstract: A non-volatile memory device includes a word line extending along a first direction; a bit line extending along a second direction; a memory unit having a read transistor coupled to the bit line, at least one two-terminal memory cell, and a select transistor, the two-terminal memory cell having a first end coupled to the word line and a second end coupled to a gate of the read transistor. The second end of the two-terminal memory cell is coupled to a common node shared by a drain of the select transistor and the gate of the read transistor.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: April 21, 2015
    Assignee: Crossbar, Inc.
    Inventor: Hagop Nazarian
  • Patent number: 9001552
    Abstract: A circuit for programming a resistive switching device includes a resistive switching device characterized by a programmable resistance, the resistive switching device comprising a first terminal, a second terminal, and a resistive switching element, a first circuit configured to supply a programming voltage to the resistive switching device and to supply a predetermined current to flow in the resistive switching device, and a second circuit coupled to the first circuit and to the resistive switching device, wherein the second circuit is configured to terminate the supply of the programming voltage to the resistive switching device when the predetermined current flows in the resistive switching device.
    Type: Grant
    Filed: June 22, 2012
    Date of Patent: April 7, 2015
    Assignee: Crossbar, Inc.
    Inventors: Sang Thanh Nguyen, Hagop Nazarian, Layne Armijo
  • Patent number: 8993397
    Abstract: A method of forming a memory device. The method provides a semiconductor substrate having a surface region. A first dielectric layer is formed overlying the surface region of the semiconductor substrate. A bottom wiring structure is formed overlying the first dielectric layer and a second dielectric material is formed overlying the top wiring structure. A bottom metal barrier material is formed to provide a metal-to-metal contact with the bottom wiring structure. The method forms a pillar structure by patterning and etching a material stack including the bottom metal barrier material, a contact material, a switching material, a conductive material, and a top barrier material. The pillar structure maintains a metal-to-metal contact with the bottom wiring structure regardless of the alignment of the pillar structure with the bottom wiring structure during etching. A top wiring structure is formed overlying the pillar structure at an angle to the bottom wiring structure.
    Type: Grant
    Filed: August 27, 2013
    Date of Patent: March 31, 2015
    Assignee: Crossbar, Inc.
    Inventor: Scott Brad Herner
  • Patent number: 8988927
    Abstract: A non-volatile variable capacitive device includes a capacitor defined over a substrate, the capacitor having an upper electrode and a resistive memory cell having a first electrode, a second electrode, and a switching layer provided between the first and second electrodes. The resistive memory cell is configured to be placed in a plurality of resistive states according to an electrical signal received. The upper electrode of the capacitive device is coupled to the second electrode of the resistive memory cell. The resistive memory cell is a two-terminal device.
    Type: Grant
    Filed: February 11, 2013
    Date of Patent: March 24, 2015
    Assignee: Crossbar, Inc.
    Inventors: Hagop Nazarian, Sung Hyun Jo
  • Patent number: 8982647
    Abstract: Providing for a two-terminal memory architecture that can mitigate sneak path current in conjunction with memory operations is described herein. By way of example, a voltage mimicking mechanism can be employed to dynamically drive un-selected bitlines of the memory architecture at a voltage observed by a selected bitline. According to these aspects, changes observed by the selected bitline can be applied to the un-selected bitlines as well. This can help reduce or avoid voltage differences between the selected bitline and the un-selected bitlines, thereby reducing or avoiding sneak path currents between respective bitlines of the memory architecture. Additionally, an input/output based configuration is provided to facilitate reduced sneak path current according to additional aspects of the subject disclosure.
    Type: Grant
    Filed: November 14, 2012
    Date of Patent: March 17, 2015
    Assignee: Crossbar, Inc.
    Inventors: Hagop Nazarian, Sang Nguyen
  • Patent number: 8975609
    Abstract: A method of forming a non-volatile memory device. A substrate is provided and a first dielectric material forms overlying the substrate. A first polysilicon material is deposited overlying the first dielectric material. A second dielectric material is deposited overlying the first polysilicon material. A second polysilicon material is deposited overlying the second dielectric material. A third dielectric material is formed overlying the second polysilicon material. The third dielectric material, the second polysilicon material, the second dielectric material, and the first polysilicon material is subjected to a first pattern and etch process to form a first wordline associated with a first switching device and a second wordline associated with a second switching device from the first polysilicon material, a third wordline and associated with a third switching device, and a fourth wordline associated with a fourth switching device from the second polysilicon material.
    Type: Grant
    Filed: April 12, 2013
    Date of Patent: March 10, 2015
    Assignee: Crossbar, Inc.
    Inventors: Harry Gee, Sung Hyun Jo, Hagop Nazarian, Scott Brad Herner
  • Patent number: 8971088
    Abstract: A method for programming a non-volatile memory device includes providing an as-fabricated state-change device having an aluminum doped zinc oxide material first electrode, a p++ polysilicon material second electrode, and a zinc oxide (ZnO) material state-change material there between. A first amplitude bias voltage is applied to the first electrode of the as-fabricated state-change device causing the ZnO material to change form an as-fabricated state to a first state. A second amplitude bias voltage having an opposite polarity having an amplitude similar to the first amplitude is applied to cause the ZnO to change from the first state to a second state substantially similar as the as-fabricated state. A third amplitude bias voltage having a same polarity to the first bias voltage and having an amplitude dissimilar to the first bias voltage is applied to cause the ZnO to change from the second state to a third state.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: March 3, 2015
    Assignee: Crossbar, Inc.
    Inventors: Sung Hyun Jo, Tanmay Kumar
  • Patent number: 8952349
    Abstract: A switching device includes a substrate; a first electrode formed over the substrate; a second electrode formed over the first electrode; a switching medium disposed between the first and second electrode; and a nonlinear element disposed between the first and second electrodes and electrically coupled in series to the first electrode and the switching medium. The nonlinear element is configured to change from a first resistance state to a second resistance state on application of a voltage greater than a threshold.
    Type: Grant
    Filed: August 6, 2013
    Date of Patent: February 10, 2015
    Assignee: Crossbar, Inc.
    Inventors: Wei Lu, Sung Hyun Jo
  • Patent number: 8946673
    Abstract: A non-volatile memory device structure includes a first conductor extending in a first direction, a second conductor extending in a second direction approximately orthogonal to the first direction, an amorphous silicon material disposed in an intersection between the first and second conductors characterized by a first resistance upon application of a first voltage, wherein the first resistance is dependent on a conductor structure comprising material from the second conductor formed in a portion of the resistive switching material, and a layer of material configured in between the second conductor and the amorphous silicon material, wherein the layer maintains at least a portion the conductor structure in the amorphous silicon material, and wherein the layer inhibits conductor species from the portion of the conductor structure from migrating away from the second conductor when a second voltage having an amplitude less than the first voltage is applied.
    Type: Grant
    Filed: August 24, 2012
    Date of Patent: February 3, 2015
    Assignee: Crossbar, Inc.
    Inventor: Tanmay Kumar
  • Patent number: 8946669
    Abstract: A method for forming a resistive memory device includes providing a substrate comprising a first metal material, forming a conductive silicon-bearing layer on top of the first metal material, wherein the conductive silicon-bearing layer comprises an upper region and a lower region, and wherein the lower region is adjacent to the first metal material, forming an amorphous layer from the upper region of the conductive silicon-bearing layer, and disposing an active metal material above the amorphous layer.
    Type: Grant
    Filed: August 15, 2012
    Date of Patent: February 3, 2015
    Assignee: Crossbar, Inc.
    Inventors: Sung Hyun Jo, Kuk-Hwan Kim, Tanmay Kumar
  • Patent number: 8947908
    Abstract: A non-volatile memory device structure includes first electrodes comprising conductive silicon-containing material, a plurality of resistive switching material stacks comprising first resistive switching material and second resistive switching material overlying the first electrode, wherein the first resistive switching material comprises a first resistance switching voltage and the second resistive switching material comprises a second resistance switching voltage less than the first amplitude, second electrodes comprising metal material overlying and electrically coupled to the plurality of resistive switching material stacks, wherein a plurality of memory elements are formed from the first plurality of electrodes, the plurality of resistive switching material stacks, and the second plurality of electrodes.
    Type: Grant
    Filed: June 17, 2013
    Date of Patent: February 3, 2015
    Assignee: Crossbar, Inc.
    Inventor: Sung Hyun Jo
  • Patent number: 8946667
    Abstract: A method for forming a resistive switching device. The method includes providing a substrate having a surface region and forming a first dielectric material overlying the surface region of the substrate. A first wiring structure overlies the first dielectric material. The method forms a first electrode material overlying the first wiring structure and a resistive switching material comprising overlying the first electrode material. An active metal material is formed overlying the resistive switching material. The active metal material is configured to form an active metal region in the resistive switching material upon application of a thermal energy characterized by a temperature no less than about 100 Degree Celsius. In a specific embodiment, the method forms a blocking material interposing the active metal material and the resistive switching material to inhibit formation of the active metal region in the resistive switching material during the subsequent processing steps.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: February 3, 2015
    Assignee: Crossbar, Inc.
    Inventors: Mark Harold Clark, Steven Maxwell, Harry Gee, Natividad Vasquez
  • Patent number: 8946046
    Abstract: A method of forming a non-volatile memory device, includes forming a first electrode above a substrate, forming a dielectric layer overlying the first electrode, forming an opening structure in a portion of the dielectric layer to expose a surface of the first electrode having an aspect ratio, forming a resistive switching material overlying the dielectric layer and filling at least a portion of the opening structure using a deposition process, the resistive switching material having a surface region characterized by a planar region and an indent structure, the indent structure overlying the first electrode, maintaining a first thickness of resistive switching material between the planar region and the first electrode, maintaining a second thickness of resistive switching material between the indent structure and the first electrode, wherein the first thickness is larger than the second thickness, and forming a second electrode overlying the resistive switching material including the indent structure.
    Type: Grant
    Filed: May 2, 2012
    Date of Patent: February 3, 2015
    Assignee: Crossbar, Inc.
    Inventor: Sung Hyun Jo
  • Patent number: 8934280
    Abstract: Providing for capacitive programming of two-terminal memory devices is described herein. By way of example, a capacitance circuit can be precharged to a predetermined program voltage to facilitate programming one or more memory cells. The capacitance circuit can be disconnected from a power source and connected instead to the memory cell(s), enabling charge stored by the capacitance circuit to discharge through the memory cell(s). A current at the memory cell(s) can program the cell, while a total amount of discharge is limited to the charge stored by the capacitance circuit. Limiting the total charge can serve to also limit joule heating of the target memory cell, power consumption of a memory device, as well as other benefits.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: January 13, 2015
    Assignee: Crossbar, Inc.
    Inventors: Harry Kuo, Hagop Nazarian, San Thanh Nguyen
  • Patent number: 8930174
    Abstract: Accurate simulation of two-terminal resistive random access memory (RRAM) behavior is accomplished by solving equations including state variables for filament length growth, filament width growth, and temperature. Such simulations are often run in a SPICE environment. Highly accurate models simulate the dynamic nature of filament propagation and multiple resistive states by using a sub-circuit to represent an RRAM cell. In the sub-circuit, voltages on floating nodes control current output while the voltage dropped across the sub-circuit controls growth and temperature characteristics. Properly executed, such a sub-circuit can accurately model filament growth at all phases of conductance including dynamic switching and a plurality of resistive states.
    Type: Grant
    Filed: March 31, 2011
    Date of Patent: January 6, 2015
    Assignee: Crossbar, Inc.
    Inventor: Wei Lu