Patents Assigned to SanDisk Technologies LLC
  • Publication number: 20170062068
    Abstract: Methods for improving channel boosting and reducing program disturb during programming of memory cells within a memory array are described. The memory array may comprise a NAND flash memory structure, such as a vertical NAND structure or a bit cost scalable (BiCS) NAND structure. In some cases, by applying continuous voltage ramping to unselected word lines during or throughout a programming operation, the boosting of channels associated with program inhibited memory cells may be improved. In one example, the slope and timing of a Vpass waveform applied to a group of unselected word lines (e.g.
    Type: Application
    Filed: November 15, 2016
    Publication date: March 2, 2017
    Applicant: SanDisk Technologies LLC
    Inventors: Peter Rabkin, Yingda Dong, Masaaki Higashitani
  • Patent number: 9582205
    Abstract: A memory system or flash memory device may include a linking or grouping of blocks that are used for dual writing. In particular, meta-blocks in the memory may be linked in such a way that enables a data transfer to simultaneously occur in two meta-blocks. The dual versions of the programming may be used for error correction. If there is a failure or write error in one of the meta-blocks, then the data from the other meta-block may be used. If there is no failure then the secondary meta-block may be erased.
    Type: Grant
    Filed: May 30, 2014
    Date of Patent: February 28, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Nagi Reddy Chodem, Abhijeet Manohar, Vijay Sivasankaran
  • Patent number: 9583198
    Abstract: Techniques are provided for avoiding over-programming which can occur on memory cells connected to a data word line at a source-side of a block of word lines. A gradient in the channel potential is created during a program voltage between the data word line and an adjacent dummy word line. This gradient generates electron-hole pairs which can contribute to over programming, where the over programming is worse at higher temperatures. In one aspect, pass voltages of unselected word lines are set to be relatively lower when the temperature is relatively higher, and when the selected word line is among a set of one or more source-side word lines. On the other hand, the pass voltages are set to be relatively higher when the temperature is relatively higher, and when the selected word line is not among the one or more source-side word lines.
    Type: Grant
    Filed: April 22, 2016
    Date of Patent: February 28, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Liang Pang, Yingda Dong, Jiahui Yuan, Jingjian Ren
  • Patent number: 9582358
    Abstract: A memory system or flash memory device may include mechanism for handling power loss with a dual programming architecture. The state of primary and secondary blocks may be reconstructed to a state immediately preceding a power loss. The reconstruction may include comparing error correction code (ECC) headers of blocks to recreate a block exchange with fewer control updates. The comparison can be used to identify a primary and secondary block. The header may identify a particular stream, identify a free block, identify a release block, and other information.
    Type: Grant
    Filed: April 30, 2015
    Date of Patent: February 28, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Dinesh Agarwal, Vijay Sivasankaran
  • Patent number: 9582435
    Abstract: In one embodiment, a memory system is provided comprising a memory die and a controller. The memory die comprises a non-volatile memory, a data latch, and an on-chip randomizer. The controller is configured to send a command to the memory die to cause the on-chip randomizer to store random data in the data latch and send data to the memory die to overwrite some, but not all, of the random data in the data latch, wherein the memory die is configured to transfer the data and random data stored in the data latch to the non-volatile memory. Other embodiments are provided.
    Type: Grant
    Filed: March 23, 2015
    Date of Patent: February 28, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Vimal Jain, Abhijeet Manohar, Aaron Lee, Anne Pao-Ling Koh
  • Patent number: 9583196
    Abstract: A system and method of programming user data into a memory cell includes receiving a first user data to be programmed in a memory controller, selecting a memory cell for programming the first user data and measuring at least one health characteristic of the selected memory cell. At least one programming parameter of the selected memory cell is adjusted and the first user data is programmed to the selected memory cell using the adjusted programming parameter corresponding to the selected memory cell.
    Type: Grant
    Filed: January 28, 2015
    Date of Patent: February 28, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Ariel Navon, Eran Sharon, Alexander Bazarsky, Noam Presman
  • Patent number: 9576657
    Abstract: A memory cell is provided that includes a vertically-oriented adjustable resistance structure including a control terminal coupled to a word line, and a reversible resistance-switching element coupled in series with and disposed above or below the vertically-oriented adjustable resistance structure.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: February 21, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Juan P. Saenz, Christopher J. Petti
  • Patent number: 9575124
    Abstract: A system for communicating high voltages for a semiconductor device is provided. One system includes a controller having an input pad and an output pad, each of the input pad and the output pad being coupled to a respective high voltage switch of the controller. The system also includes a plurality of semiconductor chips, where each of the plurality of semiconductor chips has at least one input pad coupled to a high voltage switch of a respective semiconductor chip. A high voltage that is higher than normal operation voltages of the semiconductor device is coupled from the input pad of the controller to the output pad of the controller via the coupled high voltage switches of the controller. The high voltage is further coupled from the output pad of the controller to the at least one input pad of the respective semiconductor chip via the high voltage switch coupled to the at least one input pad of the respective semiconductor chip.
    Type: Grant
    Filed: November 3, 2014
    Date of Patent: February 21, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Darmin Jin, William Chau, Brian Cheung
  • Patent number: 9576673
    Abstract: Disclosed herein are techniques for sensing multiple reference levels in non-volatile storage elements without changing the voltage on the selected word line. One aspect includes determining a first condition of a selected non-volatile storage element with respect to a first reference level based on whether a sensing transistor conducts in response to a sense voltage on a sense node. Then, a voltage on the source terminal of the sensing transistor is modified after determining the first condition with respect to the first reference level. A second condition of the selected non-volatile storage element is then determined with respect to a second reference level based on whether the sensing transistor conducts in response to the sense voltage on the sense node. This allows two different reference levels to be efficiently sensed. Dynamic power is saved due low capacitance of the sensing transistor relative to the sense node.
    Type: Grant
    Filed: October 7, 2014
    Date of Patent: February 21, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Xiaowei Jiang, Chang Siau, Siu Lung Chan
  • Patent number: 9569143
    Abstract: Techniques are disclosed herein for folding data within the same block of memory cells in 3D non-volatile storage. Data is programmed into a first string of memory cells within a block at “n” bits per memory cell. The data is folded to one or more other strings of memory cells in the same block at more than “n” bits per memory cell. For example, the data is folded to a second string at “m” bits per memory cell, where “m”>“n.” The folding operations may be performed in a way to reduce or eliminate program disturb. After the folding operation, the first string may be erased without erasing the folded data. When programming additional data into the first string at “n” bits per memory cell, memory cells on the first string that are associated with word lines for which folded data is stored are not programmed, in one aspect.
    Type: Grant
    Filed: December 11, 2015
    Date of Patent: February 14, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Rohit Sehgal, Niles Yang
  • Patent number: 9569352
    Abstract: A storage module and method for regulating garbage collection operations based on write activity of a host are disclosed. In one embodiment, a storage module determines whether the host is operating in a burst mode by determining whether write activity of the host over a time period exceeds a threshold. The write activity can comprise one or both of (i) an amount of data received from the host to be written in the storage module and (ii) a number of write commands received from the host. If the host is operating in the burst mode, the storage module limits an amount of garbage collection operations during the burst mode. When the host is no longer operating in the burst mode, the storage module increases an amount of garbage collection operations.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: February 14, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Alon Marcu, Amir Shaharabany, Hadas Oshinsky, Adir Moshen HaCohen, Einav Pnina Zilberstein
  • Patent number: 9564219
    Abstract: For a non-volatile memory device having a NAND type of architecture, techniques are presented for determining NAND strings that are slow to program, including comparing the amount of current drawn by different sets of memory cells during different write operations. These techniques are particularly applicable to memory devices have a 3D structure, such as of BiCS type, where the slow programming can arise from defects of the spacing between the memory holes, in which the NAND strings are formed, and the local interconnects, such as for connecting common source lines and which run in a vertical direction between groups of NAND strings. The slow to program NAND strings can be recorded and this information can be used when writing data to the NAND strings. Several methods of writing data along a word line that includes such slow to program cells are described.
    Type: Grant
    Filed: April 8, 2015
    Date of Patent: February 7, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Sagar Magia, Jagdish Sabde, Jayavel Pachamuthu, Ankitkumar Babariya
  • Patent number: 9564215
    Abstract: Independent sense amplifier addressing provides separate column addresses to individual sense amplifier groups within a single bay during one column address cycle. A memory system determines whether the individual memory cells or bits of a column at a bay can be skipped. For each sense amplifier group having at least one memory cell (or bit) that needs to be programmed, the system determines for the first column address whether the memory cell can be skipped. If a bit or memory cell having a first column address from the sense amplifier group can be skipped, the system determines a next bit having a column address from the group that needs to be programmed. The system groups the next column address for programming during the first column address cycle. The system can program a different column address for different sense amplifier groups within the bay during a single column address cycle.
    Type: Grant
    Filed: February 11, 2015
    Date of Patent: February 7, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Gopinath Balakrishnan, Yibo Yin, Tianhong Yan
  • Patent number: 9564404
    Abstract: Systems and methods for forming semiconductor wafers with wafer support structures includes: multiple semiconductor devices formed in multiple semiconductor dies. An electrical interconnect structure is formed over the semiconductor devices and providing electrical connections to the semiconductor devices. The electrical interconnect structure includes multiple metallization layers. At least one portion of at least one metallization layer includes variations in density of conductive lines or conducting devices as compared to the other portions of the metallization layers. At least one wafer support structure is formed substantially across a width of the semiconductor wafer. The semiconductor wafer being thinned to between about 40 um and about 200 um after the semiconductor devices formed thereon.
    Type: Grant
    Filed: January 20, 2015
    Date of Patent: February 7, 2017
    Assignee: SanDisk Technologies LLC
    Inventor: Manuel A. d'Abreu
  • Patent number: 9563213
    Abstract: Techniques for trimming an on chip ZQ calibration resistor are disclosed. The on chip ZQ calibration resistor alleviates the need for an external ZQ calibration resistor. The on chip ZQ calibration resistor allows for a faster ZQ calibration. The trimming of on chip ZQ calibration resistor may be used to account for process variation. A correction mechanism may be used to account for temperature variation. Some of the circuitry that is used for ZQ calibration is also used for trimming the on-chip calibration resistor. This circuitry may include operational amplifiers, current mirrors, transistors, etc. The dual use of the circuitry can eliminate offset errors in an operational amplifier. The dual use can eliminate current mirror mismatch. Therefore, the trimming accuracy may be improved. The dual use also reduces the amount of circuitry that is needed for trimming the on chip ZQ calibration resistor. Thus, transistor count and chip size is reduced.
    Type: Grant
    Filed: December 11, 2015
    Date of Patent: February 7, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Sravanti Addepalli, Sridhar Yadala
  • Patent number: 9564226
    Abstract: Techniques are provided for reducing current consumption while programming non-volatile storage. A smart verify is performed using a subset of memory cells. By applying the smart verify to just a subset of the memory cells current is saved. The smart verify may be used to characterize programming speed. Results of the smart verify may be used to determine a magnitude of a dummy program pulse to be applied later in the programming process. The dummy program pulse is not followed by a program verify, which reduces current. If the dummy program pulse pushes threshold voltages high enough, then those memory cells will not conduct a current when verifying later in programming. Thus, current is saved during the program verify. Also, bit lines of memory cells that received the dummy pulses do not need to be pre-charged prior to a program pulse, which can save more current.
    Type: Grant
    Filed: October 30, 2015
    Date of Patent: February 7, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Mohan Dunga, Gerrit Jan Hemink, Zhenming Zhou, Masaaki Higashitani
  • Patent number: 9564380
    Abstract: A marker pattern for enhancing resolution of a defect location along an axis in semiconductor defect analysis, and in particular, a marker pattern providing greater resolution in locating bit line defects using thermal laser stimulation methods such as OBIRCH. In an example, the marker pattern may consist of large markers, each having a set of associated small markers. Each of the small markers may be offset along an axis from each other. By identifying the small marker and its associated large marker which align with the defect, the bit line containing the defect may be more easily identified.
    Type: Grant
    Filed: August 26, 2014
    Date of Patent: February 7, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Yoshihiro Suzumura, Masato Takeo
  • Patent number: 9563555
    Abstract: Resources of an address space are managed in dynamically sized ranges, extents, sets, and/or blocks. The address space may be divided into regions, each corresponding to a different, respective allocation granularity. Allocating a block within a first region of the address space may comprise allocating a particular number of logical addresses (e.g., a particular range, set, and/or block of addresses), and allocating a block within a different region may comprise allocating a different number of logical addresses. The regions may be configured to reduce the metadata overhead needed to identify free address blocks (and/or maintain address block allocations), while facilitating efficient use of the address space for differently sized data structures.
    Type: Grant
    Filed: April 17, 2013
    Date of Patent: February 7, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: David Flynn, Nick Piggin, Nisha Talagala
  • Publication number: 20170033121
    Abstract: A fabrication process is provided for a 3D stacked non-volatile memory device which provides a source contact to a bottom of a memory hole in a stack without exposing a programmable material lining of an interior sidewall of the memory hole and without exposing a channel forming region also lining an interior of the memory hole to an energetic and potentially damaging etch environment. The stack includes alternating control gate layers and dielectric layers on a substrate, and the memory hole is etched through the stack before lining an interior sidewall thereof with the programmable material and then with the channel forming material. The process avoids a need to energetically etch down through the memory hole to open up a source contact hole near the bottom of the channel forming material by instead etching upwardly from beneath the memory hole.
    Type: Application
    Filed: October 13, 2016
    Publication date: February 2, 2017
    Applicant: SanDisk Technologies LLC
    Inventors: Masato Miyamoto, Yuji Fukano
  • Patent number: 9558009
    Abstract: A system may be provided that includes a random access memory, a non-volatile solid state memory, a serial non-volatile semiconductor memory, and a memory controller. The non-volatile solid state memory may include a boot block and a code partition. The serial non-volatile semiconductor memory stores a last written boot sector identifier. The memory controller may be configured to read the last written boot sector identifier from the serial non-volatile semiconductor memory and find a last written boot sector of the boot block based on the last written boot sector identifier read from the serial non-volatile semiconductor memory.
    Type: Grant
    Filed: September 11, 2015
    Date of Patent: January 31, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Injae Choi, Hyung-Bae Park