Patents by Inventor Qiangfei Xia

Qiangfei Xia 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: 20240046083
    Abstract: A system includes a sensor, a plurality of cells, and a processor. The sensor includes a plurality of transducers arranged on a planar surface and includes a first transducer and a second transducer. The first transducer is configured to produce an analog output signal corresponding to a detected input signal. The cells are arranged in a network and include a first and a second cell and are disposed proximate the sensor in a three-dimensional stacking fashion. The first transducer and the second transducer are electrically coupled to the first cell and the second cell in one-to-one relation. The first cell includes a plurality of inputs and a first cell output. Each input is coupled to an output of a corresponding plurality of neighboring cells. The first cell includes a first memristor and a bridge circuit configured to receive the analog output signal and provide a current corresponding to the detected input signal in a pixel-parallel fashion.
    Type: Application
    Filed: July 25, 2023
    Publication date: February 8, 2024
    Inventors: Qiangfei Xia, Vigneshwar Ravichandran, Tina Maurer
  • Patent number: 11586884
    Abstract: A diffusive memristor device and an electronic device for emulating a biological neuron is disclosed. The diffusive memristor device includes a bottom electrode, a top electrode formed opposite the bottom electrode, and a dielectric layer disposed between the top electrode and the bottom electrode. The dielectric layer comprises an oxide doped with a metal.
    Type: Grant
    Filed: February 8, 2019
    Date of Patent: February 21, 2023
    Assignee: University of Massachusetts
    Inventors: Jianhua Yang, Qiangfei Xia, Mark McLean, Qing Wu
  • Publication number: 20210382696
    Abstract: A true random number generator device based on a diffusive memristor is disclosed. The random number generator device includes a diffusive memristor driven by a pulse generator circuit. The diffusive memristor produces a stochastically switched output signal. A comparator circuit receives the stochastically switched output signal from the diffusive memristor and generates an output signal having a random pulse width. An AND gate logic circuit is driven by a clock signal and the output signal from the comparator circuit. The AND gate logic circuit produces a combined output signal. A counter circuit receives the combined output signal from the AND gate logic circuit and generates a random bit string output signal.
    Type: Application
    Filed: August 20, 2021
    Publication date: December 9, 2021
    Inventors: Jianhua Yang, Qiangfei Xia, Hao Jiang
  • Patent number: 11126403
    Abstract: A true random number generator device based on a diffusive memristor is disclosed. The random number generator device includes a diffusive memristor driven by a pulse generator circuit. The diffusive memristor produces a stochastically switched output signal. A comparator circuit receives the stochastically switched output signal from the diffusive memristor and generates an output signal having a random pulse width. An AND gate logic circuit is driven by a clock signal and the output signal from the comparator circuit. The AND gate logic circuit produces a combined output signal. A counter circuit receives the combined output signal from the AND gate logic circuit and generates a random bit string output signal.
    Type: Grant
    Filed: March 28, 2019
    Date of Patent: September 21, 2021
    Assignee: University of Massachusetts
    Inventors: Jianhua Yang, Qiangfei Xia, Hao Jiang
  • Patent number: 10740672
    Abstract: In one aspect, an apparatus includes a diffusive memristor, and a capacitor integrated in series with the diffusive memristor, wherein the apparatus exhibits volatile memcapacitive behavior. In another aspect, a device includes a transistor, and a memcapacitor integrated onto the gate of the transistor, wherein the memcapacitor exhibits volatile memcapacitive behavior. The memcapacitor includes a diffusive memristor, and a capacitor integrated in series with the diffusive memristor, wherein the gate dielectric of the transistor is replaced with the memcapacitor. In another aspect, an artificial neuron device includes a transistor, a volatile memcapacitor that is configured to operate as an electrically floating gate of the transistor, and one or more synaptic circuits that are coupled to the volatile memcapacitor. The volatile memcapacitor includes a diffusive memristor, and a capacitor integrated in series with the diffusive memristor.
    Type: Grant
    Filed: April 1, 2019
    Date of Patent: August 11, 2020
    Assignee: Univerity of Massachusetts
    Inventors: Jianhua Yang, Qiangfei Xia, Zhongrui Wang, Qing Wu, Mark R. McLean
  • Patent number: 10741759
    Abstract: A diffusive memristor device and an electronic device for emulating a biological synapse are disclosed. The diffusive memristor device includes a bottom electrode, a top electrode formed opposite the bottom electrode, and a dielectric layer disposed between the top electrode and the bottom electrode. The dielectric layer comprises silver doped silicon oxynitride (SiOxNy:Ag). In an alternate implementation, the dielectric layer comprises silver doped silicon oxide (Ag:SiO2). An electronic synapse emulation device is also disclosed. The synapse emulation device includes a diffusive memristor device, a drift memristor device connected in series with the diffusive memristor device, a first voltage pulse generator connected to the diffusive memristor device, and a second voltage pulse generator connected to the drift memristor device. Application of a signal from one of the first voltage pulse generator or the second voltage pulse generator allows the synapse emulation device to exhibit long-term plasticity.
    Type: Grant
    Filed: September 26, 2018
    Date of Patent: August 11, 2020
    Assignee: University of Massachusetts
    Inventors: Jianhua Yang, Qiangfei Xia, Mark McLean, Qing Wu, Mark Barnell
  • Publication number: 20200227635
    Abstract: A diffusive memristor device and an electronic device for emulating a biological synapse are disclosed. The diffusive memristor device includes a bottom electrode, a top electrode formed opposite the bottom electrode, and a dielectric layer disposed between the top electrode and the bottom electrode. The dielectric layer comprises silver doped silicon oxynitride (SiOxNy:Ag). In an alternate implementation, the dielectric layer comprises silver doped silicon oxide (Ag:SiO2). An electronic synapse emulation device is also disclosed. The synapse emulation device includes a diffusive memristor device, a drift memristor device connected in series with the diffusive memristor device, a first voltage pulse generator connected to the diffusive memristor device, and a second voltage pulse generator connected to the drift memristor device. Application of a signal from one of the first voltage pulse generator or the second voltage pulse generator allows the synapse emulation device to exhibit long-term plasticity.
    Type: Application
    Filed: September 26, 2018
    Publication date: July 16, 2020
    Inventors: Jianhua Yang, Qiangfei Xia, Mark McLean, Qing Wu, Mark Barnell
  • Patent number: 10580679
    Abstract: Disclosed herein is a method comprising disposing on a first substrate a two-dimensional exfoliatable material; patterning an exfoliatable material using a photoresist in a manner such that a portion of the photoresist remains in contact with the two-dimensional exfoliatable material after the patterning; disposing a polymer layer on the two-dimensional exfoliatable material to form a printing block; contacting a substrate with the printing block; and removing the polymer layer and the photoresist from the printing block to leave behind the patterned exfoliatable material on the substrate.
    Type: Grant
    Filed: September 22, 2016
    Date of Patent: March 3, 2020
    Assignee: THE UNIVERSITY OF MASSACHUSETTS
    Inventors: Qiangfei Xia, Peng Lin
  • Publication number: 20190303744
    Abstract: In one aspect, an apparatus includes a diffusive memristor, and a capacitor integrated in series with the diffusive memristor, wherein the apparatus exhibits volatile memcapacitive behavior. In another aspect, a device includes a transistor, and a memcapacitor integrated onto the gate of the transistor, wherein the memcapacitor exhibits volatile memcapacitive behavior. The memcapacitor includes a diffusive memristor, and a capacitor integrated in series with the diffusive memristor, wherein the gate dielectric of the transistor is replaced with the memcapacitor. In another aspect, an artificial neuron device includes a transistor, a volatile memcapacitor that is configured to operate as an electrically floating gate of the transistor, and one or more synaptic circuits that are coupled to the volatile memcapacitor. The volatile memcapacitor includes a diffusive memristor, and a capacitor integrated in series with the diffusive memristor.
    Type: Application
    Filed: April 1, 2019
    Publication date: October 3, 2019
    Inventors: Jianhua Yang, Qiangfei Xia, Zhongrui Wang, Qing Wu, Mark R. McLean
  • Publication number: 20190303104
    Abstract: A true random number generator device based on a diffusive memristor is disclosed. The random number generator device includes a diffusive memristor driven by a pulse generator circuit. The diffusive memristor produces a stochastically switched output signal. A comparator circuit receives the stochastically switched output signal from the diffusive memristor and generates an output signal having a random pulse width. An AND gate logic circuit is driven by a clock signal and the output signal from the comparator circuit. The AND gate logic circuit produces a combined output signal. A counter circuit receives the combined output signal from the AND gate logic circuit and generates a random bit string output signal.
    Type: Application
    Filed: March 28, 2019
    Publication date: October 3, 2019
    Inventors: Jianhua Yang, Qiangfei Xia, Hao Jiang
  • Publication number: 20190244088
    Abstract: A diffusive memristor device and an electronic device for emulating a biological neuron is disclosed. The diffusive memristor device includes a bottom electrode, a top electrode formed opposite the bottom electrode, and a dielectric layer disposed between the top electrode and the bottom electrode. The dielectric layer comprises an oxide doped with a metal.
    Type: Application
    Filed: February 8, 2019
    Publication date: August 8, 2019
    Inventors: Jianhua Yang, Qiangfei Xia, Mark McLean, Qing Wu
  • Patent number: 10186660
    Abstract: A resistance switching device is disclosed and is fabricated to create a memristor device. The memristor device includes a substrate and a platinum bottom electrode formed on the substrate. A tantalum top electrode is formed opposite the bottom electrode, and an electrical insulator layer is disposed between the top electrode and the bottom electrode, wherein the electrical insulator layer comprises hafnium oxide. In an alternate implementation, a titanium nitride layer is deposited on the substrate, which then allows a reduced thickness platinum bottom electrode layer to be deposited on the titanium nitride layer.
    Type: Grant
    Filed: March 28, 2017
    Date of Patent: January 22, 2019
    Assignee: University of Massachusetts
    Inventors: Qiangfei Xia, Hao Jiang, Jianhua Yang
  • Publication number: 20180287058
    Abstract: A resistance switching device is disclosed and is fabricated to create a memristor device. The memristor device includes a substrate and a platinum bottom electrode formed on the substrate. A tantalum top electrode is formed opposite the bottom electrode, and an electrical insulator layer is disposed between the top electrode and the bottom electrode, wherein the electrical insulator layer comprises hafnium oxide. In an alternate implementation, a titanium nitride layer is deposited on the substrate, which then allows a reduced thickness platinum bottom electrode layer to be deposited on the titanium nitride layer.
    Type: Application
    Filed: March 28, 2017
    Publication date: October 4, 2018
    Inventors: Qiangfei Xia, Hao Jiang, Jianhua Yang
  • Publication number: 20180277413
    Abstract: Disclosed herein is a method comprising disposing on a first substrate a two-dimensional exfoliatable material; patterning an exfoliatable material using a photoresist in a manner such that a portion of the photoresist remains in contact with the two-dimensional exfoliatable material after the patterning; disposing a polymer layer on the two-dimensional exfoliatable material to form a printing block; contacting a substrate with the printing block; and removing the polymer layer and the photoresist from the printing block to leave behind the patterned exfoliatable material on the substrate.
    Type: Application
    Filed: September 22, 2016
    Publication date: September 27, 2018
    Applicant: THE UNIVERSITY OF MASSACHUSETTS
    Inventors: Qiangfei Xia, Peng Lin
  • Patent number: 9998106
    Abstract: A memristive radio frequency (RF) switch circuit comprises a first metal electrode and a second metal electrode arranged on an insulating substrate and separated by an air gap, wherein the air gap is fifty nanometers (50 nm) or less, and wherein applying and removing an enabling voltage to the memristive RF switch enables the memristive RF switch to pass RF signals between the first electrode and the second electrode even when the enabling voltage is removed from the memristive switch, and wherein applying and removing a disabling voltage to the memristive switch disables the memristive switch.
    Type: Grant
    Filed: April 17, 2015
    Date of Patent: June 12, 2018
    Assignee: University of Massachusetts
    Inventors: Qiangfei Xia, Joseph Bardin, Shuang Pi
  • Patent number: 9871077
    Abstract: A memory device includes one or more first semiconductor ridges formed on a first semiconductor wafer. The first semiconductor ridges are configured to be first electrodes. The memory device also includes one or more second semiconductor ridges formed on a second semiconductor wafer. The second semiconductor ridges are configured to be second electrodes and are placed orthogonally on top of the first semiconductor ridges forming a crossbar structure, with sharp edges of the first semiconductor ridges coupled to sharp edges of the second semiconductor ridges. Each area of coupling of a first semiconductor ridge and a second semiconductor ridge is configured to be a memory cell. In addition, the memory device includes a compound layer covering the sharp edges of at least one of the first semiconductor ridges or the second semiconductor ridges. The compound layer is configured to be a switching layer.
    Type: Grant
    Filed: December 8, 2014
    Date of Patent: January 16, 2018
    Assignee: University of Massachusetts
    Inventor: Qiangfei Xia
  • Publication number: 20160351256
    Abstract: A memory device includes one or more first semiconductor ridges formed on a first semiconductor wafer. The first semiconductor ridges are configured to be first electrodes. The memory device also includes one or more second semiconductor ridges formed on a second semiconductor wafer. The second semiconductor ridges are configured to be second electrodes and are placed orthogonally on top of the first semiconductor ridges forming a crossbar structure, with sharp edges of the first semiconductor ridges coupled to sharp edges of the second semiconductor ridges. Each area of coupling of a first semiconductor ridge and a second semiconductor ridge is configured to be a memory cell. In addition, the memory device includes a compound layer covering the sharp edges of at least one of the first semiconductor ridges or the second semiconductor ridges. The compound layer is configured to be a switching layer.
    Type: Application
    Filed: December 8, 2014
    Publication date: December 1, 2016
    Inventor: Qiangfei Xia
  • Publication number: 20150303376
    Abstract: A memristive radio frequency (RF) switch circuit comprises a first metal electrode and a second metal electrode arranged on an insulating substrate and separated by an air gap, wherein the air gap is fifty nanometers (50 nm) or less, and wherein applying and removing an enabling voltage to the memristive RF switch enables the memristive RF switch to pass RF signals between the first electrode and the second electrode even when the enabling voltage is removed from the memristive switch, and wherein applying and removing a disabling voltage to the memristive switch disables the memristive switch.
    Type: Application
    Filed: April 17, 2015
    Publication date: October 22, 2015
    Inventors: Qiangfei Xia, Joseph Bardin, Shuang Pi
  • Patent number: 9068921
    Abstract: An analyzer is disclosed herein. The analyzer encompasses a substrate having a surface with a plurality of distinct V-grooves formed therein. An input flow channel is configured to intersect and fluidly communicate with each of the plurality of distinct V-grooves at respective input points, and an output flow channel is configured to intersect and fluidly communicate with each of the plurality of distinct V-grooves at respective output points.
    Type: Grant
    Filed: March 7, 2009
    Date of Patent: June 30, 2015
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Wei Wu, Qiangfei Xia, Shih-Yuan Wang, Jingjing Li
  • Patent number: 8879300
    Abstract: Various embodiments of the present invention are directed to nanoscale electronic devices that provide nonvolatile memristive switching. In one aspect, a two-terminal device (600) comprises a first electrode (602), a second electrode (604), and an active region (606) disposed between the first electrode and the second electrode. The active region includes a mobile dopant (608), and a fast drift ionic species (610). The fast drift ionic species drifts into a diode-like electrode/active region interface temporarily increasing conductance across the interface when a write voltage is applied to the two-terminal device to switch the device conductance.
    Type: Grant
    Filed: April 22, 2010
    Date of Patent: November 4, 2014
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Jianhua Yang, Wei Wu, Qiangfei Xia