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).

  • Patent number: 8854881
    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: Grant
    Filed: April 8, 2013
    Date of Patent: October 7, 2014
    Assignee: Unity Semiconductor Corporation
    Inventors: Christophe Chevallier, Seow Fong Lim, Chang Hua Siau
  • Patent number: 8854888
    Abstract: Circuitry for generating voltage levels operative to perform data operations on non-volatile re-writeable memory arrays are disclosed. In some embodiments an integrated circuit includes a substrate and a base layer formed on the substrate to include active devices configured to operate within a first voltage range. Further, the integrated circuit can include a cross-point memory array formed above the base layer and including re-writable two-terminal memory cells that are configured to operate, for example, within a second voltage range that is greater than the first voltage range. Conductive array lines in the cross-point memory array are electrically coupled with the active devices in the base layer. The integrated circuit also can include X-line decoders and Y-line decoders that include devices that operate in the first voltage range. The active devices can include other active circuitry such as sense amps for reading data from the memory cells, for example.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: October 7, 2014
    Assignee: Unity Semiconductor Corporation
    Inventors: Christophe Chevallier, Chang Hua Siau
  • Publication number: 20140219006
    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 8, 2014
    Publication date: August 7, 2014
    Applicant: Unity Semiconductor Corporation
    Inventors: Christophe J. Chevallier, Chang Hua Siau
  • Patent number: 8737151
    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: October 4, 2011
    Date of Patent: May 27, 2014
    Assignee: Unity Semiconductor Corporation
    Inventors: Bruce Bateman, Darrell Rinerson, Christophe Chevallier, Chang Hua Siau
  • Publication number: 20140140122
    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: September 12, 2013
    Publication date: May 22, 2014
    Applicant: Unity Semiconductor Corporation
    Inventor: Chang Hua Siau
  • Patent number: 8705260
    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: Grant
    Filed: December 27, 2012
    Date of Patent: April 22, 2014
    Assignee: Unity Semiconductor Corporation
    Inventors: Christophe Chevallier, Seow Fong Lim, Chang Hua Siau
  • Patent number: 8654565
    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: October 23, 2012
    Date of Patent: February 18, 2014
    Assignee: Unity Semiconductor Corporation
    Inventors: Christophe Chevallier, Chang Hua Siau
  • Patent number: 8638584
    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: Grant
    Filed: February 2, 2010
    Date of Patent: January 28, 2014
    Assignee: Unity Semiconductor Corporation
    Inventors: Christophe Chevallier, Sri Rama Namala, Chang Hua Siau, David Eggleston
  • Publication number: 20130308410
    Abstract: Circuitry for generating voltage levels operative to perform data operations on non-volatile re-writeable memory arrays are disclosed. In some embodiments an integrated circuit includes a substrate and a base layer formed on the substrate to include active devices configured to operate within a first voltage range. Further, the integrated circuit can include a cross-point memory array formed above the base layer and including re-writable two-terminal memory cells that are configured to operate, for example, within a second voltage range that is greater than the first voltage range. Conductive array lines in the cross-point memory array are electrically coupled with the active devices in the base layer. The integrated circuit also can include X-line decoders and Y-line decoders that include devices that operate in the first voltage range. The active devices can include other active circuitry such as sense amps for reading data from the memory cells, for example.
    Type: Application
    Filed: December 4, 2012
    Publication date: November 21, 2013
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventors: Christophe Chevallier, Chang Hua Siau
  • Publication number: 20130294136
    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. The global bit line and/or the selected local bit line can be biased to compensate for the Process Voltage Temperature (PVT) variation.
    Type: Application
    Filed: July 3, 2013
    Publication date: November 7, 2013
    Inventors: Chang Hua Siau, Bruce Lynn Bateman
  • Patent number: 8565003
    Abstract: A multi-layer cross-point memory array comprises one or more word line (WL) layers, one or more bit line (BL) layers interleaved with the one or more WL layers, and a plurality of memory layers, each memory layer disposed between an adjacent WL layer and an adjacent BL layer, and each memory layer including memory elements configured between cross-points of WLs and BLs of the adjacent WL and BL layers. Memory elements in successive memory layers of the memory array are configured with opposing orientations, so that half-selected memory elements arising during times when data operations are being performed on selected memory elements in the memory array are subjected to stress voltages of a polarity of which they are least susceptible to being disturbed. The memory elements can be discrete re-writeable non-volatile two-terminal memory elements that are fabricated as part of a BEOL fabrication process used to fabricate the memory array.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: October 22, 2013
    Assignee: Unity Semiconductor Corporation
    Inventor: Chang Hua Siau
  • Patent number: 8559209
    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: Grant
    Filed: June 10, 2011
    Date of Patent: October 15, 2013
    Assignee: Unity Semiconductor Corporation
    Inventor: Chang Hua Siau
  • Publication number: 20130229856
    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: April 8, 2013
    Publication date: September 5, 2013
    Inventors: Christophe Chevallier, Seow Fong Lim, Chang Hua Siau
  • Publication number: 20130215667
    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: December 27, 2012
    Publication date: August 22, 2013
    Applicant: Unity Semiconductor Corporation
    Inventors: Christophe Chevallier, Seow Fong Lim, Chang Hua Siau
  • Patent number: 8427868
    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: Grant
    Filed: February 1, 2011
    Date of Patent: April 23, 2013
    Assignee: Unity Semiconductor Corporation
    Inventors: Christophe J. Chevallier, Seow Fong Lim, Chang Hua Siau
  • Patent number: 8395929
    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: April 17, 2012
    Date of Patent: March 12, 2013
    Assignee: Unity Semiconductor Corporation
    Inventor: Chang Hua Siau
  • Patent number: 8363443
    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: Grant
    Filed: January 31, 2011
    Date of Patent: January 29, 2013
    Assignee: Unity Semiconductor Corporation
    Inventors: Christophe J. Chevallier, Seow Fong Lim, Chang Hua Siau
  • Patent number: 8351264
    Abstract: Circuitry for generating voltage levels operative to perform data operations on non-volatile re-writeable memory arrays are disclosed. In some embodiments an integrated circuit includes a substrate and a base layer formed on the substrate to include active devices configured to operate within a first voltage range. Further, the integrated circuit can include a cross-point memory array formed above the base layer and including re-writable two-terminal memory cells that are configured to operate, for example, within a second voltage range that is greater than the first voltage range. Conductive array lines in the cross-point memory array are electrically coupled with the active devices in the base layer. The integrated circuit also can include X-line decoders and Y-line decoders that include devices that operate in the first voltage range. The active devices can include other active circuitry such as sense amps for reading data from the memory cells, for example.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: January 8, 2013
    Assignee: Unity Semiconductor Corporation
    Inventors: Christophe Chevallier, Chang Hua Siau
  • Publication number: 20130003437
    Abstract: A multi-layer cross-point memory array comprises one or more word line (WL) layers, one or more bit line (BL) layers interleaved with the one or more WL layers, and a plurality of memory layers, each memory layer disposed between an adjacent WL layer and an adjacent BL layer, and each memory layer including memory elements configured between cross-points of WLs and BLs of the adjacent WL and BL layers. Memory elements in successive memory layers of the memory array are configured with opposing orientations, so that half-selected memory elements arising during times when data operations are being performed on selected memory elements in the memory array are subjected to stress voltages of a polarity of which they are least susceptible to being disturbed. The memory elements can be discrete re-writeable non-volatile two-terminal memory elements that are fabricated as part of a BEOL fabrication process used to fabricate the memory array.
    Type: Application
    Filed: June 28, 2011
    Publication date: January 3, 2013
    Applicant: UNITY SEMICONDUCTOR CORPORATION
    Inventor: Chang Hua Siau
  • Patent number: 8339867
    Abstract: A margin restore fuse element is described, including a latch configured to store data, a first memory element coupled to the latch and configured to store a first resistive value, a second memory element coupled to the latch and configured to store a second resistive value, a restore circuit coupled to the latch, the first memory element, and the second memory element, the restore circuit being configured to perform a restore data operation to substantially restore the first and second memory elements to the first and second resistive values, respectively. The latch, restore circuit, and other circuitry can be formed FEOL on a substrate (e.g., a semiconductor wafer) as part of a microelectronics fabrication process and the fuse element and memory elements can be formed BEOL over the substrate as part of another microelectronics fabrication process. The fuse and memory elements can be included in a two-terminal non-volatile memory cell.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: December 25, 2012
    Assignee: Unity Semiconductor Corporation
    Inventor: Chang Hua Siau