Patents by Inventor Chang Hua Siau

Chang Hua Siau 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: 20120314468
    Abstract: A memory array includes wordlines, local bitlines, two-terminal memory elements, global bitlines, and local-to-global bitline pass gates and gain stages. The memory elements are formed between the wordlines and local bitlines. Each local bitline is selectively coupled to an associated global bitline, by way of an associated local-to-global bitline pass gate. During a read operation when a memory element of a local bitline is selected to be read, a local-to-global gain stage is configured to amplify a signal on or passing through the local bitline to an amplified signal on or along an associated global bitline. The amplified signal, which in one embodiment is dependent on the resistive state of the selected memory element, is used to rapidly determine the memory state stored by the selected memory element.
    Type: Application
    Filed: June 10, 2011
    Publication date: December 13, 2012
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: Chang Hua Siau, Bruce Bateman
  • Publication number: 20120314477
    Abstract: Embodiments of the invention relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to preserve states of memory elements in association with data operations using variable access signal magnitudes for other memory elements, such as implemented in third dimensional memory technology. In some embodiments, a memory device can include a cross-point array with resistive memory elements. An access signal generator can modify a magnitude of a signal to generate a modified magnitude for the signal to access a resistive memory element associated with a word line and a subset of bit lines. A tracking signal generator is configured to track the modified magnitude of the signal and to apply a tracking signal to other resistive memory elements associated with other subsets of bit lines, the tracking signal having a magnitude at a differential amount from the modified magnitude of the signal.
    Type: Application
    Filed: June 10, 2011
    Publication date: December 13, 2012
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventor: Chang Hua Siau
  • Publication number: 20120307542
    Abstract: Embodiments relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to implement a memory architecture that includes local bit lines for accessing subsets of memory elements, such as memory elements based on third dimensional memory technology. In at least some embodiments, an integrated circuit includes a cross-point memory array formed above a logic layer. The cross-point memory array includes X-lines and Y-lines, of which at least one Y-line includes groups of Y-line portions. Each of the Y-line portions can be arranged in parallel with other Y-line portions within a group of the Y-line portions. Also included are memory elements disposed between a subset of the X-lines and the group of the Y-line portions. In some embodiments, a decoder is configured to select a Y-line portion from the group of Y-line portions to access a subset of the memory elements.
    Type: Application
    Filed: August 17, 2012
    Publication date: December 6, 2012
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: Chang Hua Siau, Christophe Chevallier, Darrell Rinerson, Seow Fong Lim, Sri Namala
  • Patent number: 8305796
    Abstract: Embodiments of the invention relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to generate access signals to facilitate memory operations in scaled arrays of memory elements, such as memory implemented in third dimensional memory technology formed BEOL directly on top of a FEOL substrate that includes data access circuitry. In at least some embodiments, a non-volatile memory device can include a cross-point array having resistive memory elements disposed among word lines and subsets of bit lines, and an access signal generator. The access signal generator can be configured to modify a magnitude of a signal to generate a modified magnitude for the signal to access a resistive memory element associated with a word line and a subset of bit lines. The modified magnitude can be a function of the position of the resistive memory element in the cross-point array.
    Type: Grant
    Filed: March 20, 2012
    Date of Patent: November 6, 2012
    Assignee: Unity Semiconductor Corporation
    Inventors: Christophe Chevallier, Chang Hua Siau
  • Publication number: 20120257438
    Abstract: Circuitry for restoring data values in re-writable non-volatile memory is disclosed. An integrated circuit includes a memory access circuit and a sensing circuit configured to sense a data signal during a read operation to at least one two-terminal non-volatile cross-point memory array. Each memory array includes a plurality of two-terminal memory elements. A plurality of the memory arrays can be fabricated over the substrate and vertically stacked on one another. Further, the integrated circuit can include a margin manager circuit configured to manage a read margin for the two-terminal memory elements substantially during the read operation, thereby providing for contemporaneous read and margin determination operations. Stored data read from the two-terminal memory elements may have a value of the stored data restored (e.g., re-written to the same cell or another cell) if the value is not associated with a read margin (e.g., a hard programmed or hard erased state).
    Type: Application
    Filed: June 21, 2012
    Publication date: October 11, 2012
    Applicant: Unity Semiconductor Corporation
    Inventors: Chang Hua Siau, Christophe Chevallier
  • Patent number: 8270193
    Abstract: Embodiments relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to implement a memory architecture that includes local bit lines for accessing subsets of memory elements, such as memory elements based on third dimensional memory technology. In at least some embodiments, an integrated circuit includes a cross-point memory array formed above a logic layer. The cross-point memory array includes X-lines and Y-lines, of which at least one Y-line includes groups of Y-line portions. Each of the Y-line portions can be arranged in parallel with other Y-line portions within a group of the Y-line portions. Also included are memory elements disposed between a subset of the X-lines and the group of the Y-line portions. In some embodiments, a decoder is configured to select a Y-line portion from the group of Y-line portions to access a subset of the memory elements.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: September 18, 2012
    Assignee: Unity Semiconductor Corporation
    Inventors: Chang Hua Siau, Christophe Chevallier, Darrell Rinerson, Seow Fong Lim, Sri Rama Namala
  • Publication number: 20120201086
    Abstract: A configuration for biasing conductive array lines in a two-terminal cross-point memory array is disclosed. The configuration includes applying a read voltage to a selected X-conductive array line while applying an un-select voltage thru a biasing element to a remaining plurality of un-selected X-conductive array lines. A plurality of Y-conductive array lines are initially biased to some voltage (e.g., 0V) and then allowed to float unbiased after a predetermined amount of time has passed, some event has occurred, or both. As one example the event that triggers the floating of the plurality of Y-conductive array lines can be the read voltage reaching a predetermined magnitude. The array can be formed BEOL and include a plurality of two-terminal memory cells with each memory cell including a memory element and optionally a non-ohmic device (NOD) that are electrically in series with each other and with the two terminals of the memory cell.
    Type: Application
    Filed: April 17, 2012
    Publication date: August 9, 2012
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventor: Chang Hua Siau
  • Publication number: 20120176832
    Abstract: Embodiments of the invention relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to generate access signals to facilitate memory operations in scaled arrays of memory elements, such as memory implemented in third dimensional memory technology formed BEOL directly on top of a FEOL substrate that includes data access circuitry. In at least some embodiments, a non-volatile memory device can include a cross-point array having resistive memory elements disposed among word lines and subsets of bit lines, and an access signal generator. The access signal generator can be configured to modify a magnitude of a signal to generate a modified magnitude for the signal to access a resistive memory element associated with a word line and a subset of bit lines. The modified magnitude can be a function of the position of the resistive memory element in the cross-point array.
    Type: Application
    Filed: March 20, 2012
    Publication date: July 12, 2012
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: CHRISTOPHE CHEVALLIER, CHANG HUA SIAU
  • Patent number: 8208287
    Abstract: Circuitry for restoring data values in re-writable non-volatile memory is disclosed. An integrated circuit includes a memory access circuit and a sensing circuit configured to sense a data signal during a read operation to at least one two-terminal non-volatile cross-point memory array. Each memory array includes a plurality of two-terminal memory elements. A plurality of the memory arrays can be fabricated over the substrate and vertically stacked on one another. Further, the integrated circuit can include a margin manager circuit configured to manage a read margin for the two-terminal memory elements substantially during the read operation, thereby providing for contemporaneous read and margin determination operations. Stored data read from the two-terminal memory elements may have a value of the stored data restored (e.g., re-written to the same cell or another cell) if the value is not associated with a read margin (e.g., a hard programmed or hard erased state).
    Type: Grant
    Filed: July 12, 2011
    Date of Patent: June 26, 2012
    Inventors: Christophe Chevallier, Chang Hua Siau
  • Patent number: 8159858
    Abstract: A configuration for biasing conductive array lines in a two-terminal cross-point memory array is disclosed. The configuration includes applying a read voltage to a selected X-conductive array line while applying an un-select voltage thru a biasing element to a remaining plurality of un-selected X-conductive array lines. A plurality of Y-conductive array lines are initially biased to some voltage (e.g., 0V) and then allowed to float unbiased after a predetermined amount of time has passed, some event has occurred, or both. As one example the event that triggers the floating of the plurality of Y-conductive array lines can be the read voltage reaching a predetermined magnitude. The array can be formed BEOL and include a plurality of two-terminal memory cells with each memory cell including a memory element and optionally a non-ohmic device (NOD) that are electrically in series with each other and with the two terminals of the memory cell.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: April 17, 2012
    Inventor: Chang Hua Siau
  • Publication number: 20120075914
    Abstract: A low read current architecture for memory. Bit lines of a cross point memory array are allowed to be charged by a selected word line until a minimum voltage differential between a memory state and a reference level is assured.
    Type: Application
    Filed: October 4, 2011
    Publication date: March 29, 2012
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: BRUCE BATEMAN, DARRELL RINERSON, CHRISTOPHE CHEVALLIER, CHANG HUA SIAU
  • Patent number: 8139409
    Abstract: Embodiments of the invention relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to generate access signals to facilitate memory operations in scaled arrays of memory elements, such as memory implemented in third dimensional memory technology formed BEOL directly on top of a FEOL substrate that includes data access circuitry. In at least some embodiments, a non-volatile memory device can include a cross-point array having resistive memory elements disposed among word lines and subsets of bit lines, and an access signal generator. The access signal generator can be configured to modify a magnitude of a signal to generate a modified magnitude for the signal to access a resistive memory element associated with a word line and a subset of bit lines. The modified magnitude can be a function of the position of the resistive memory element in the cross-point array.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: March 20, 2012
    Inventors: Christophe Chevallier, Chang Hua Siau
  • Publication number: 20110267871
    Abstract: Circuitry for restoring data values in re-writable non-volatile memory is disclosed. An integrated circuit includes a memory access circuit and a sensing circuit configured to sense a data signal during a read operation to at least one two-terminal non-volatile cross-point memory array. Each memory array includes a plurality of two-terminal memory elements. A plurality of the memory arrays can be fabricated over the substrate and vertically stacked on one another. Further, the integrated circuit can include a margin manager circuit configured to manage a read margin for the two-terminal memory elements substantially during the read operation, thereby providing for contemporaneous read and margin determination operations. Stored data read from the two-terminal memory elements may have a value of the stored data restored (e.g., re-written to the same cell or another cell) if the value is not associated with a read margin (e.g., a hard programmed or hard erased state).
    Type: Application
    Filed: July 12, 2011
    Publication date: November 3, 2011
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: Chang Hua SIAU, Christophe CHEVALLIER
  • Patent number: 8031545
    Abstract: A low read current architecture for memory. Bit lines of a cross point memory array are allowed to be charged by a selected word line until a minimum voltage differential between a memory state and a reference level is assured.
    Type: Grant
    Filed: April 19, 2010
    Date of Patent: October 4, 2011
    Inventors: Darrell Rinerson, Christophe Chevallier, Chang Hua Siau
  • Publication number: 20110188284
    Abstract: Embodiments of the invention relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to implement circuits configured to compensate for parameter variations in layers of memory by adjusting access signals during memory operations. In some embodiments, memory cells are based on third dimensional memory technology. In at least some embodiments, an integrated circuit includes multiple layers of memory, a layer including sub-layers of semiconductor material. The integrated circuit also includes an access signal generator configured to generate an access signal to facilitate an access operation, and a characteristic adjuster configured to adjust the access signal for each layer in the multiple layers of memory.
    Type: Application
    Filed: February 1, 2011
    Publication date: August 4, 2011
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: Christophe J. Chevallier, Seow Fong Lim, Chang Hua Siau
  • Publication number: 20110188282
    Abstract: Embodiments of the invention relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to implement memory architectures configured to enhance throughput for cross point arrays including memory elements, such as memory elements based on third dimensional memory technology. In at least some embodiments, an integrated circuit includes arrays that include memory elements being formed BEOL above a FEOL logic layer within a boundary in a plane parallel to a substrate, and array lines. Further, the integrated circuit includes array line decoders disposed in the logic layer within a region located coextensive with the boundary and between the substrate and the arrays. In some embodiments, the disposition of peripheral circuitry, such as the array line decoders, under the arrays can preserve or optimize die efficiency for throughput enhancement.
    Type: Application
    Filed: February 2, 2010
    Publication date: August 4, 2011
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: Christophe J. Chevallier, Sri Namala, Chang Hua Siau, David Eggleston
  • Publication number: 20110188281
    Abstract: Embodiments relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to implement a memory architecture that includes local bit lines for accessing subsets of memory elements, such as memory elements based on third dimensional memory technology. In at least some embodiments, an integrated circuit includes a cross-point memory array formed above a logic layer. The cross-point memory array includes X-lines and Y-lines, of which at least one Y-line includes groups of Y-line portions. Each of the Y-line portions can be arranged in parallel with other Y-line portions within a group of the Y-line portions. Also included are memory elements disposed between a subset of the X-lines and the group of the Y-line portions. In some embodiments, a decoder is configured to select a Y-line portion from the group of Y-line portions to access a subset of the memory elements.
    Type: Application
    Filed: January 29, 2010
    Publication date: August 4, 2011
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: Chang Hua Siau, Christophe Chevallier, Darrell Rinerson, Seow Fong Lim, Sri Namala
  • Publication number: 20110188289
    Abstract: Embodiments of the invention relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to generate access signals to facilitate memory operations in scaled arrays of memory elements, such as memory implemented in third dimensional memory technology formed BEOL directly on top of a FEOL substrate that includes data access circuitry. In at least some embodiments, a non-volatile memory device can include a cross-point array having resistive memory elements disposed among word lines and subsets of bit lines, and an access signal generator. The access signal generator can be configured to modify a magnitude of a signal to generate a modified magnitude for the signal to access a resistive memory element associated with a word line and a subset of bit lines. The modified magnitude can be a function of the position of the resistive memory element in the cross-point array.
    Type: Application
    Filed: January 29, 2010
    Publication date: August 4, 2011
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: Christophe Chevallier, Chang Hua Siau
  • Publication number: 20110188283
    Abstract: Embodiments of the invention relate generally to semiconductors and memory technology, and more particularly, to systems, integrated circuits, and methods to implement circuits configured to compensate for parameter variations that affect the operation of memory elements, such as memory elements based on third dimensional memory technology. In at least some embodiments, an integrated circuit includes a cross-point array comprising memory elements disposed among word lines and bit lines, where a parameter can affect the operating characteristics of a memory element. The integrated circuit further includes a data signal adjuster configured to modify the operating characteristic to compensate for a deviation from a target value for the operating characteristic based on the parameter. In some embodiments, the memory element, such as a resistive memory element, is configured to generate a data signal having a magnitude substantially at the target value independent of variation in the parameter.
    Type: Application
    Filed: January 31, 2011
    Publication date: August 4, 2011
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: Christophe J. Chevallier, Seow Fong Lim, Chang Hua Siau
  • Patent number: 7978501
    Abstract: Circuitry and methods for restoring data values in non-volatile memory are disclosed. An integrated circuit includes a memory access circuit and a sensing circuit configured to sense a data signal during a read operation to at least one two-terminal non-volatile cross-point memory array. Each memory array includes a plurality of two-terminal memory cells. A plurality of the memory arrays can be fabricated over the substrate and vertically stacked on one another. Further, the integrated circuit can include a margin manager circuit configured to manage a read margin for the two-terminal memory cells substantially during the read operation, thereby providing for contemporaneous read and margin determination operations. Stored data read from the two-terminal memory cells may have a value of the stored data restored (e.g., re-written to the same cell or another cell) if the value is not associated with a read margin (e.g., a hard programmed or hard erased state).
    Type: Grant
    Filed: November 9, 2010
    Date of Patent: July 12, 2011
    Inventors: Christophe Chevallier, Chang Hua Siau