Patents Assigned to SanDisk Technologies LLC
  • Patent number: 10283567
    Abstract: A method is provided that includes forming a word line above a substrate, the word line disposed in a first direction, forming a bit line above the substrate, the bit line disposed in a second direction perpendicular to the first direction, forming a nonvolatile memory material between the word line and the bit line, the nonvolatile memory material including a semiconductor material layer and conductive oxide material layer, forming a first barrier material layer between the word line and the nonvolatile memory material, forming a second barrier material layer between the bit line and the nonvolatile memory material, and forming a memory cell including the nonvolatile memory material at an intersection of the bit line and the word line.
    Type: Grant
    Filed: February 24, 2017
    Date of Patent: May 7, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Juan Saenz, Deepak Kamalanathan, Guangle Zhou, Ming-Che Wu, Tanmay Kumar
  • Patent number: 10283200
    Abstract: An apparatus may include a controller configured to communicate with a plurality of dies via a signal path. The controller may notify the dies of its desire to communicate with a target die. In response, the dies may set on-die termination resistances of two or more of the dies to a low resistance value, which in turn may set an overall termination resistance of the memory dies to be lower than the low resistance value. The lower overall termination resistance may be closer to a characteristic impedance of a portion of the signal path comprising packaging components of a packaging of the dies compared to the low resistance value, thereby reducing impedance mismatch between the characteristic impedance of the packaging components and the termination resistance.
    Type: Grant
    Filed: September 10, 2018
    Date of Patent: May 7, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Nimrod Hermesh, Eliran Kanza
  • Patent number: 10282251
    Abstract: A system and method is disclosed for managing firmware in a non-volatile memory system having a multi-processor controller. The controller may be configured with a plurality of processors. Each of the plurality of processors may retrieve and check the integrity of firmware for a respective one of the other processors while the processor engaged in checking the respective one of the other processors is in an idle state.
    Type: Grant
    Filed: September 7, 2016
    Date of Patent: May 7, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Ilya Gusev, Yevgeny Zagalsky, Beniamin Kantor, Shay Benisty, Judah Gamliel Hahn
  • Patent number: 10284182
    Abstract: A complementary signal path may include an amplifier circuit configured to receive a pair of complementary input signals and a data alignment circuit configured to output a pair of complementary output signals in response to the pair of complementary input signals. A control circuit may detect duty cycle distortion in the pair of complementary output signals and perform a duty cycle correction process to remove the distortion. To do so, the control circuit may search for target current amounts in response to the duty cycle distortion and inject a control current into the amplifier circuit at the target current amounts.
    Type: Grant
    Filed: June 30, 2017
    Date of Patent: May 7, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Primit Modi, Venkatesh Ramachandra, Tianyu Tang, Srinivas Rajendra
  • Publication number: 20190130971
    Abstract: Apparatuses, systems, and methods are disclosed for write-time prevention of data retention failures for non-volatile memory. An apparatus may include an array of non-volatile memory cells and a controller. A controller may be configured to perform a write operation for at least one cell. A controller may be configured to identify, during a write operation, one or more cells for which a characteristic of the one or more identified cells is associated with data retention failure. A controller may be configured to modify a write operation for one or more identified cells.
    Type: Application
    Filed: October 31, 2017
    Publication date: May 2, 2019
    Applicant: SanDisk Technologies LLC
    Inventor: Bijesh Rajamohanan
  • Publication number: 20190130964
    Abstract: Apparatuses, systems, methods, and computer program products are disclosed for performing a group read refresh. An apparatus includes a plurality of memory groups. An apparatus includes an operation circuit that performs an operation on a selected memory group of a plurality of memory groups. An apparatus includes a remediation circuit that performs a countermeasure operation on an unselected memory group of a plurality of memory groups in response to an operation on a selected memory group.
    Type: Application
    Filed: October 31, 2017
    Publication date: May 2, 2019
    Applicant: SanDisk Technologies LLC
    Inventors: Philip David Reusswig, Grishma Shah, Nian Niles Yang
  • Publication number: 20190130982
    Abstract: Over a period of operation, non-volatile memory can develop a residual resistance that is impractical to remove. For example, in a NAND string of memory cells, trapped charge may build up in a region between the bit lines and drain side select gates, so that even when all the devices of a NAND string are in an “on” state, the NAND string will not conduct. This effect will skew both hard bit data determinations, indicating the data state of a selected memory cell, and soft bit data determinations which may correlate to the reliability of the hard bit data. Techniques are described to factor in such excessive residual resistance when determining the soft bit data.
    Type: Application
    Filed: October 31, 2017
    Publication date: May 2, 2019
    Applicant: SanDisk Technologies LLC
    Inventors: Philip David Reusswig, Nian Niles Yang, Anubhav Khandelwal
  • Patent number: 10276792
    Abstract: Systems and methods for providing a Barrier Modulated Cell (BMC) structure that may comprise a reversible resistance-switching memory element within a memory array are described. The BMC structure may include a barrier layer comprising a layer of amorphous germanium or amorphous silicon germanium paired with a conductive metal oxide, such as titanium dioxide (TiO2), strontium titanate (SrTiO3), or a binary metal oxide. The BMC structure may include a conductive metal oxide in series with an amorphous layer of a low bandgap material. The low bandgap material may comprise a semiconductor material with a bandgap energy (Eg) less than 1.0 eV. The improved BMC structure may be used for providing multi-level memory elements within a three dimensional memory array.
    Type: Grant
    Filed: February 6, 2018
    Date of Patent: April 30, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Ming-Che Wu, Tanmay Kumar
  • Patent number: 10276248
    Abstract: Techniques for reducing a downshift in the threshold voltage of a select gate transistor of a memory device. Due to an electric field in a NAND string, holes can move in a charge-trapping layer from a dummy memory cell to a select gate transistor and combine with electrons in the transistor, reducing the threshold voltage. In one approach, the electric field is reduced at the end of a sensing operation by ramping down the voltage of the dummy memory cells before ramping down the voltage of the select gate transistors. The ramp down of the voltage of the selected memory cells can occur after ramping down the voltage of the dummy memory cells and before ramping down of the voltage of the select gate transistors. A further option involves elevating the voltage of the select gate transistors before it is ramped down.
    Type: Grant
    Filed: December 20, 2017
    Date of Patent: April 30, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Ching-Huang Lu, Vinh Diep
  • Patent number: 10275170
    Abstract: A memory system may be configured to perform immediate folding of data from a low storage density area to a high storage density area. A low storage density target area may be monitored, and when a capacity of the low storage density target area reaches a threshold level, data stored in the low storage density target area may be folded to an associated high storage density target area. The memory system may utilize a pointer system to manage the folding of data. The pointer system may also be utilized for read operations in order to avoid updating address mapping tables for both the low storage density and the high storage density areas.
    Type: Grant
    Filed: April 10, 2017
    Date of Patent: April 30, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Narendhiran Chinnaanangur Ravimohan, Muralitharan Jayaraman, Balakumar Rajendran, Satya Kesav Gundabathula, Ramkumar Ramamurthy, Rohit Sathyanarayan
  • Patent number: 10276251
    Abstract: A memory system performs verification when writing to memory. It is possible that the memory system may be missing some components (or components may be otherwise unavailable). To account for missing or unavailable components when performing verification, the memory system uses a pattern of data that includes a mask identifying the missing or unavailable components. The mask is used to force a predetermined result of the verification for the missing or unavailable portions of the memory structure so that results of the verification that correspond to the missing or unavailable components are not counted as errors.
    Type: Grant
    Filed: December 21, 2017
    Date of Patent: April 30, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Sukhminder Singh Lobana, Kirubakaran Periyannan, Ankitkumar Babariya
  • Patent number: 10276783
    Abstract: A four terminal magnetoresistive memory cell comprises a magnetic tunnel junction stack, a ferroelectric layer and a non-ferromagnetic spin polarization layer between the magnetic tunnel junction stack and the ferroelectric layer. The magnetic tunnel junction includes a first layer with fixed direction of magnetization, a free layer capable of changing direction of magnetization and an insulation layer between the first layer and the free layer. The non-ferromagnetic spin polarization layer is configured to generate perpendicular spin polarization in response to electrical current through the non-ferromagnetic spin polarization layer and a voltage received at the ferroelectric layer. The perpendicular spin polarization applies a torque on the free layer to change direction of magnetization of the free layer.
    Type: Grant
    Filed: June 9, 2017
    Date of Patent: April 30, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Goran Mihajlovic, Jeffrey S. Lille
  • Patent number: 10268584
    Abstract: A storage device includes a nonvolatile memory. The storage device further includes a hint derivation module for automatically deriving, from host accesses to the storage device, hints regarding expected future host accesses to a table that maps logical memory addresses to physical memory addresses in the nonvolatile memory. The storage device further includes an adaptive host memory buffer (HMB) caching module for using the hints to identify portions of the table to cache in the HMB and for caching the identified portions in the HMB, which is external to the storage device and accessible by the storage device via a bus.
    Type: Grant
    Filed: February 22, 2016
    Date of Patent: April 23, 2019
    Assignee: SanDisk Technologies LLC
    Inventor: Judah Gamliel Hahn
  • Patent number: 10269421
    Abstract: Technology is described herein for caching residual data in latches during a write operation of non-volatile storage. When writing data at the request of a host, it is possible for there to be some residual data that cannot be programmed at two (or more) bits per memory cell into a page of memory cells, given the programming scheme being used. This residual data may be cached in latches. The residual data from the latches may be combined with other data from the host to increase programming speed when programming, for example, sequential data using a full sequence programming scheme. Also, caching the residual data in latches keeps write amplification low.
    Type: Grant
    Filed: November 30, 2016
    Date of Patent: April 23, 2019
    Assignee: SanDisk Technologies LLC
    Inventor: Dinesh Agarwal
  • Patent number: 10268387
    Abstract: Technology is described herein for performing memory array operations in multiple memory dies in parallel. The memory dies, or groups of non-volatile memory cells on the memory dies, may exhibit different performance times for memory array operations. For example, non-volatile memory cells on one memory die may program more slowly than those on another memory die. The performance times of the memory dies (or groups of the memory cells on different memory dies) may be characterized relative to one another. Memory dies having similar performance times may be placed into the same meta-groups. Meta-groups may be formed at the die, zone, or block level. The meta-groups can be re-formed over the lifetime of the memory system, which can account for changes in performance times over the lifetime of the memory system.
    Type: Grant
    Filed: January 4, 2017
    Date of Patent: April 23, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Narendhiran Cr, Satya Kesav Gundabathula, Muralitharan Jayaraman, Chittoor Devarajan Sunilkumar, Satrajit Chakraborty
  • Patent number: 10268400
    Abstract: A non-volatile memory system may include a controller configured for parsing a host file system, identifying a location of a host file system directory and tracking directory entries of files deleted from the host file system directory but having valid data mappings in the logical-to-physical mapping table. The controller may then store the location of the host file system directory, monitor activity in the host file system directory and track validity status information for use in optimizing a compaction process. The compaction process may include segregating into separate compaction destination blocks valid data based on the stored validity status such that data valid in both the host file system directory and the logical-to-physical mapping table is in compaction destination blocks separate from data having valid logical-to-physical mapping entries but associated with deleted host file system directory entries.
    Type: Grant
    Filed: September 3, 2015
    Date of Patent: April 23, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Narendhiran Chinaaanangur Ravimohan, Muralitharan Jayaraman
  • Patent number: 10269444
    Abstract: Techniques and memory devices are provided in which bit line short circuits are detected and groups of bit lines are masked off. A process tests groups of bit lines which are connected to a sense circuit. A masking latch is provided to store test results for each group of bit lines. Once the testing of a group is completed, the test result is communicated to a controller. Moreover, the same masking latch can store and communicate test results for multiple groups of bit lines which are connected to a sense circuit. In a user mode, a masking latch stores masking data for each group of bit lines. In response to a power on reset, the masking data is loaded into the masking latches and remains there over multiple write and read operation, until a next power on reset occurs.
    Type: Grant
    Filed: April 19, 2017
    Date of Patent: April 23, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Anurag Nigam, Yukeun Sim, Jingwen Ouyang, Yingchang Chen
  • Patent number: 10268396
    Abstract: Storage divisions of a non-volatile storage medium may have a writable state and an unwritable state. Storage divisions may be reclaimed by, inter alia, resetting the storage division from an unwritable state to a writable state. Writable storage divisions may be used to service incoming storage requests. If no writable storage divisions are available, requests may stall. One or more storage divisions may be held in a writable state to avoid stall conditions. This, however, may increase the erase dwell time of the storage divisions, which can result in increased wear and reduce the usable life of the storage device. Storage divisions may be prepared for use such that the storage divisions are transitioned to a writable state such that erase dwell time of the storage divisions is reduced, and the storage divisions are available as needed to service incoming requests.
    Type: Grant
    Filed: August 22, 2017
    Date of Patent: April 23, 2019
    Assignee: SanDisk Technologies LLC
    Inventor: Gary Janik
  • Patent number: 10269435
    Abstract: A memory device and associated techniques for reducing program disturb of memory cells which are formed in a two-tier stack with an increased distance between memory cells at an interface between the tiers. After a verify test in a program loop, a different timing is used for decreasing the word line voltages of the interface memory cells compared to the remaining memory cells. In one aspect, the start of the decrease of the word line voltages of the interface memory cells is delayed. In another aspect, the word line voltages of the interface memory cells is decreased to an intermediate level and held for a time period before being decreased further. In another aspect, the word line voltages of the interface memory cells are decreased at a lower rate.
    Type: Grant
    Filed: November 16, 2017
    Date of Patent: April 23, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Hong-Yan Chen, Yingda Dong
  • Publication number: 20190115391
    Abstract: A non-volatile memory uses phase change memory (PCM) cells in a three dimensional vertical cross-point structure, in which multiple layers of word lines run in a horizontal direction and bit lines run in a vertical direction. The memory cells are located in a recessed region of the word lines and are separated from the bit line by an ovonic threshold switch. A surfactant lining of the word line recess in which the phase change memory material is placed improves stability of the resistance state of the memory cells, allowing for improved multi-state operation.
    Type: Application
    Filed: January 12, 2018
    Publication date: April 18, 2019
    Applicant: SanDisk Technologies LLC
    Inventors: Federico Nardi, Christopher J. Petti, Gerrit Jan Hemink