Multiple Pulses (e.g., Ramp) Patents (Class 365/185.19)
  • Patent number: 8971130
    Abstract: In a memory cell array, a plurality of memory cells connected to a plurality of word lines and a plurality of bit lines are arranged in a matrix. A control circuit controls the potentials of said plurality of word lines and said plurality of bit lines. In an erase operation, the control circuit erases an n number of memory cells (n is a natural number equal to or larger than 2) of said plurality of memory cells at the same time using a first erase voltage, carries out a verify operation using a first verify level, finds the number of cells k (k?n) exceeding the first verify level, determines a second erase voltage according to the number k, and carries out an erase operation again using the second erase voltage.
    Type: Grant
    Filed: October 25, 2012
    Date of Patent: March 3, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Noboru Shibata
  • Patent number: 8971120
    Abstract: According to one embodiment, a semiconductor memory device includes memory cells, word lines, a driver circuit, and a control circuit. The memory cells are stacked above a semiconductor substrate, and each includes a charge accumulation layer and control gate. The word lines are coupled to the control gates. The driver circuit repeats a programming operation to write data in a memory cell coupled to a selected word line. In the programming operation, a first voltage is applied to the selected word line, a second voltage to a first unselected word line, and a third voltage to a second unselected word line. The control circuit steps up the first voltage and steps down the second voltage in repeating the programming.
    Type: Grant
    Filed: February 6, 2014
    Date of Patent: March 3, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroshi Maejima
  • Patent number: 8971121
    Abstract: Embodiments of the present disclosure provide methods, devices, modules, and systems for operating memory cells. One method includes: performing an erase operation on a selected group of memory cells, the selected group including a number of reference cells and a number of data cells; performing a programming monitor operation on the number of reference cells as part of the erase operation; and determining a number of particular operating parameters associated with operating the number of data cells at least partially based on the programming monitor operation performed on the number of reference cells.
    Type: Grant
    Filed: August 20, 2013
    Date of Patent: March 3, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Akira Goda, Andrei Mihnea
  • Patent number: 8971112
    Abstract: Method of programming a multi-level memory cell may include transferring one or more values between an auxiliary latch of the multi-level memory cell and a most significant bit (MSB) latch of the multi-level memory cell and/or between the auxiliary latch and a least significant bit (LSB) latch of the multi-level memory cell while programming the multi-level memory cell.
    Type: Grant
    Filed: October 4, 2013
    Date of Patent: March 3, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Luca Crippa, Rino Micheloni
  • Publication number: 20150055417
    Abstract: A method and apparatus for controlling the operation of flash memory are provided. The apparatus for controlling the operation of flash memory includes a control unit and a voltage adjustment unit. The control unit outputs a control signal adapted to change one or more of the program, erase and read voltage conditions for the flash memory to the voltage adjustment unit in response to the input of a PUF mode selection signal. The voltage adjustment unit changes the one or more of the program, erase and read voltage conditions for the flash memory in response to the input of the control signal.
    Type: Application
    Filed: July 21, 2014
    Publication date: February 26, 2015
    Inventors: Moon-Seok KIM, Sang-Kyung YOO, Sanghan LEE
  • Patent number: 8958233
    Abstract: The present disclosure includes apparatuses and methods including stabilization of resistive memory. A number of embodiments include applying a programming signal to a resistive memory cell, wherein the programming signal includes a first portion having a first polarity and a second portion having a second polarity, wherein the second polarity is opposite the first polarity.
    Type: Grant
    Filed: October 18, 2011
    Date of Patent: February 17, 2015
    Assignee: Micron Technology, Inc.
    Inventor: Xiaonan Chen
  • Patent number: 8953386
    Abstract: A program operation for a set of non-volatile storage elements. A count is maintained of a number of program pulses which are applied to an individual storage element in a slow programming mode, and an associated bit line voltage is adjusted based on the count. Different bit line voltages can be used, having a common step size or different steps sizes. As a result, the change in threshold voltage of the storage element within the slow programming mode, with each program pulse can be made uniform, resulting in improved programming accuracy. Latches maintain the count of program pulses experienced by the associated storage element, while in the slow programming mode. The storage element is in a fast programming mode when its threshold voltage is below a lower verify level, and in the slow programming mode when its threshold voltage is between the lower verify level and a higher verify level.
    Type: Grant
    Filed: October 25, 2012
    Date of Patent: February 10, 2015
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Ken Oowada, Masaaki Higashitani, Man L. Mui
  • Patent number: 8953381
    Abstract: A semiconductor memory device includes a memory cell array having memory cells coupled to a plurality of word lines and a peripheral circuit group configured to supply a pass voltage to unselected word lines among the plurality of word lines, wherein the peripheral circuit group stepwise raises the pass voltage supplied to the unselected word lines to a target level.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: February 10, 2015
    Assignee: SK Hynix Inc.
    Inventor: Jong Soon Leem
  • Patent number: 8953378
    Abstract: A method for programming a split gate memory cell includes performing a first programming of the split gate memory cell in a first programming cycle of the split gate memory cell; and, subsequent to the performing the first programming of the split gate memory cell, performing a second programming of the split gate memory cell in the first programming cycle, wherein the first programming is characterized as one of source-side injection (SSI) programming and channel-initiated secondary electron (CHISEL) programming, and the second programming is characterized as the other of SSI programming and CHISEL programming.
    Type: Grant
    Filed: June 28, 2012
    Date of Patent: February 10, 2015
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Cheong Min Hong, Sung-Taeg Kang
  • Patent number: 8953382
    Abstract: Integrated circuit memory devices include a plurality of vertically-stacked strings of nonvolatile memory cells having respective vertically-arranged channel regions therein electrically coupled to an underlying substrate. A control circuit is provided, which is configured to drive the vertical channel regions with an erase voltage that is ramped from a first voltage level to a higher second voltage level during an erase time interval. This ramping of the erase voltage promotes time efficient erasure of vertically stacked nonvolatile memory cells with reduced susceptibility to inadvertent programming of ground and string selection transistors (GST, SST).
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: February 10, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jaesung Sim, Jungdal Choi
  • Patent number: 8947953
    Abstract: Among other things, techniques for facilitating a write operation to a bit cell are provided. A pulse generator initializes lowering of an internal voltage level associated with a bit cell that is to be written to by a write operation. In this way, the bit cell is placed into a writeable voltage state, such that a potential of the bit cell can be overcome by the write operation. A voltage detector sends a reset signal to the pulse generator based upon the pulse generator lowering the internal voltage level past a reset trigger level. Responsive to receiving the reset signal, the pulse generator initializes charging of the internal voltage level to an original voltage level. In this way, the lowering of the internal voltage level is controlled so that one or more other bit cells are not affected (e.g., suffer data retention failure) by the relatively lower internal voltage level.
    Type: Grant
    Filed: December 30, 2012
    Date of Patent: February 3, 2015
    Assignee: Taiwan Semiconductor Manufacturing Company Limited
    Inventors: Wei Min Chan, Yi-Tzu Chen, Wei-Cheng Wu, Yen-Huei Chen, Hau-Tai Shieh
  • Patent number: 8947939
    Abstract: A memory device includes a plurality of memory cells arranged in series in the semiconductor body, such as a NAND string, having a plurality of word lines. A selected memory cell is programmed by hot carrier injection. The program operation is based on metering a flow of carriers between a first semiconductor body region on a first side of the selected cell in the NAND string and a second semiconductor body region on a second side of the selected cell. A program potential higher than a hot carrier injection barrier level is applied to the selected cell, and then the drain to source voltage across the selected cell and the flow of carriers in the selected cell reach a level sufficient to support hot carrier injection, which is controlled by a switch cell adjacent the selected cell.
    Type: Grant
    Filed: October 6, 2010
    Date of Patent: February 3, 2015
    Assignee: Macronix International Co., Ltd.
    Inventors: Ping-Hung Tsai, Jyun-Siang Huang, Wen-Jer Tsai
  • Patent number: 8942038
    Abstract: A nonvolatile memory recycles previously written blocks by reassigning binary logic states and further programming memory cells with modified parameters. Cells are written twice between erase operations, thus reducing wear, and providing higher endurance. Flags indicate whether blocks are recycled, and what parameters to use in programming and reading the blocks.
    Type: Grant
    Filed: April 2, 2013
    Date of Patent: January 27, 2015
    Assignee: SanDisk Technologies, Inc.
    Inventors: Nian Niles Yang, Abhijeet Manohar
  • Patent number: 8942046
    Abstract: A nonvolatile memory device comprises cell strings formed in a direction substantially perpendicular to a substrate and is configured to select memory cells in units corresponding to a string selection line. The device selects a page to be programmed among pages sharing a common word line, determines a level of a program voltage to be provided to the selected page according to a location of a string selection line corresponding to the selected page, and writes data in the selected page using the determined level of the program voltage.
    Type: Grant
    Filed: February 7, 2013
    Date of Patent: January 27, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Donghun Kwak
  • Publication number: 20150023107
    Abstract: A first non-selected word line including a word line adjacent to a selected word line is applied with a first write pass voltage. Furthermore, a second non-selected word line which is a non-selected word line excluding the first non-selected word line is applied with a second write pass voltage smaller than a program voltage. A control circuit, in the write operation, raises the first write pass voltage toward a first target value by executing a voltage raising operation having a first voltage rise width, X times, and raises the second write pass voltage toward a second target value by executing a voltage raising operation having a second voltage rise width, Y times. The first voltage rise width is larger than the second voltage rise width, and X times is fewer than Y times.
    Type: Application
    Filed: October 9, 2014
    Publication date: January 22, 2015
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tatsuo IZUMI, Eietsu TAKAHASHI
  • Publication number: 20150023106
    Abstract: Methods and systems are disclosed for adaptive erase recovery of non-volatile memory (NVM) cells within NVM systems. The adaptive erase recovery embodiments adaptively adjust the erase recovery discharge rate and/or discharge time based upon the size of NVM block(s) being erased and operating temperature. In one example embodiment, the erase recovery discharge rate is adjusted by adjusting the number of discharge transistors enabled within the discharge circuitry, thereby adjusting the discharge current for erase recovery. A lookup table is used to store erase recovery discharge rates and/or discharge times associated with NVM block sizes to be recovered and/or operating temperature. By adaptively controlling erase recovery discharge rates and/or times, the disclosed embodiments improve overall erase performance for a wide range of NVM block sizes while avoiding possible damage to high voltage circuitry within the NVM system.
    Type: Application
    Filed: July 16, 2013
    Publication date: January 22, 2015
    Inventors: Chen He, Yanzhuo Wang, Fuchen Mu
  • Patent number: 8937837
    Abstract: A system for erasing non-volatile storage system that reduces the voltage across the transistor that interfaces between the sense amplifier and the bit line so that the transistor can be made smaller. Additionally, the use of the lower voltage allows for various components to be positioned closer to each other. The use of smaller components and smaller spaces between components allows the non-volatile storage system to include more memory cells, thereby providing the ability to store more data.
    Type: Grant
    Filed: May 3, 2013
    Date of Patent: January 20, 2015
    Assignee: Sandisk Technologies Inc.
    Inventors: Mohan Vamsi Dunga, Kwang-Ho Kim, Masaaki Higashitani
  • Patent number: 8934301
    Abstract: An error correcting method of a memory controller which controls a nonvolatile memory device includes judging whether first read data read from the nonvolatile memory device is correctable; reading second read data from the nonvolatile memory device when the first read data is uncorrectable; and correcting an error of the first read data based on error information of the second read data and error information of the first read data.
    Type: Grant
    Filed: August 29, 2012
    Date of Patent: January 13, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Eun-Jin Yun
  • Patent number: 8934302
    Abstract: A method is provided for operating a nonvolatile memory comprising memory cells stacked on a substrate. The method comprises counting a number of program loops performed in a first program operation of selected memory cells connected to a selected wordline, and controlling an increment of a program voltage between successive program loops of a second program operation of the selected memory cells according to the counted number.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: January 13, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Dong-Hun Kwak
  • Patent number: 8934298
    Abstract: A nonvolatile memory device is programmed by performing a plurality of program loops each comprising sequentially applying first through n-th program pulses (n>1) to a selected wordline connected to a page of memory cells to be programmed, and incrementing each of the first through n-th program pulses prior to a next program loop, wherein the first through n-th program pulses are used to program selected memory cells to respective first through n-th program states, and during application of an i-th program pulse among the first through n-th program pulses (1<i<n), applying a program inhibit voltage to bitlines connected to selected memory cells to be programmed to the first through (i?1)-th program states and applying a program permission voltage to bitlines connected to selected memory cells to be programmed to the i-th through n-th program states.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: January 13, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sang-Soo Park, Jae-Yong Jeong
  • Patent number: 8929150
    Abstract: A nonvolatile memory apparatus includes: a memory cell area including a plurality of memory cells connected to a word line and a bit line; a program time controller configured to determine a program voltage application time for a selected word line, as the selected word line is selected in response to a program command and an address signal; and a controller configured to apply a program voltage to the selected word line according to the program voltage application time determined by the program time controller.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: January 6, 2015
    Assignee: SK Hynix Inc.
    Inventor: Chul Woo Yang
  • Patent number: 8929134
    Abstract: A method of programming a NAND flash memory cell string. The method includes a pre-boost stage configured to elevate channel voltage of a selected memory cell, and a boost stage is introduced after the pre-boost stage. The pre-boost stage has at least the following steps of biasing a bit line to a first voltage, biasing a string select transistor to a second voltage; and ramping down the string select transistor to the first voltage. In particular, the second voltage is higher than the first voltage.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: January 6, 2015
    Assignee: Macronix International Co., Ltd.
    Inventors: Chu Yung Liu, Hsing Wen Chang, Yao Wen Chang, Tao Cheng Lu
  • Patent number: 8929135
    Abstract: A non-volatile semiconductor memory device includes an electrically data rewritable non-volatile semiconductor memory cell and a write circuit for writing data in the memory cell, the write circuit writing a data in the memory cells by supplying a write voltage Vpgm and a write control voltage VBL to the memory cell, continuing the writing of the data in the memory cell by changing the value of the write control voltage VBL in response to an advent of a first write state of the memory cell and inhibiting any operation of writing a data to the memory cell by further changing the value of the write control voltage VBL to Vdd in response to an advent of a second write state of the memory cell.
    Type: Grant
    Filed: November 12, 2013
    Date of Patent: January 6, 2015
    Assignees: Kabushiki Kaisha Toshiba, SanDisk Corporation
    Inventors: Tomoharu Tanaka, Jian Chen
  • Publication number: 20150003167
    Abstract: A method of programming a memory cell of a nonvolatile memory device by executing a plurality of program loops comprises detecting whether a loop count or a level of a program pulse to be applied to the memory cell is within a specific range, wherein the specific range is an operation section in which a level of a current peak flowing into the bitline increases up to a reference value or more, charging a bitline of the memory cell at a first charging speed or a second charging speed slower than the first charging speed according to a result of the detection, and applying the program pulse to a wordline of the memory cell.
    Type: Application
    Filed: March 24, 2014
    Publication date: January 1, 2015
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: YOON-HEE CHOI, SANG-WAN NAM
  • Publication number: 20150003152
    Abstract: A write method of a storage device includes determining whether to perform a coarse program operation based on information about memory cells of a memory device, in response to a determination that the coarse program operation is to be performed, programming data in the memory device by performing the coarse program operation and a fine program operation, and in response to a determination that the coarse program operation is not to be performed, programming data in the memory device by performing the fine program operation.
    Type: Application
    Filed: February 25, 2014
    Publication date: January 1, 2015
    Inventors: DongHun KWAK, Dongkyo SHIM, KITAE PARK, Hyun-Wook PARK
  • Patent number: 8923056
    Abstract: A non-volatile memory device includes a memory cell block including a plurality of memory cells, a plurality of page buffer groups including a plurality of page buffers coupled to bit lines of the memory cell block, a pass/fail check circuit coupled to the plurality of page buffers and configured to perform a pass/fail check operation of comparing a total amount of current varying according to verify data sensed from the memory cells and stored in the page buffers with an amount of reference current corresponding to the number of allowed bits, and a control circuit configured to control the pass/fail check circuit by stopping, when a fail signal is generated during the pass/fail check operation currently being performed on a page buffer group among the plurality of page buffer groups, the pass/fail check operation on the remaining page buffer groups.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: December 30, 2014
    Assignee: SK Hynix Inc.
    Inventor: Min Su Kim
  • Patent number: 8923046
    Abstract: A semiconductor memory device includes a memory cell array including first memory cells and second memory cells connected to at least one word line, a circuit group configured to perform a pre-program operation on the first memory cells using a target voltage and a main program operation on the first memory cells and the second memory cells using a final target voltage, and a control circuit configured to set the target voltage depending on variations in threshold voltages of the first memory cells caused by the main program operation of the second memory cells.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: December 30, 2014
    Assignee: SK Hynix Inc.
    Inventor: Yoo Hyun Noh
  • Patent number: 8923061
    Abstract: Provided is a programming method of a nonvolatile memory device which includes a plurality of strings each including a source select transistor, a plurality of memory cells, and a drain select transistor which are connected in series between a common source line and a bit line. The programming method includes: applying a first voltage to the common source line during a first period in which a channel of a plurality of memory cells of an unselected string is floated; and applying a second voltage increased more than the first in voltage to the common source line during a second period in which a selected memory cell is programmed, when a selected word line belongs to a word line group adjacent to the common source line.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: December 30, 2014
    Assignee: SK Hynix Inc.
    Inventor: Tae-Gyun Kim
  • Patent number: 8923064
    Abstract: A semiconductor memory device includes a memory array including a plurality of memory cells, and a peripheral circuit configured to perform an erase operation by supplying a first erase voltage to selected memory cells and perform an erase verify operation by supplying an erase verify voltage to the selected memory cells, wherein the peripheral circuit is configured to increase the first erase voltage to a first level at a first rising rate for a first rising period and increase the first erase voltage to a first target level at a second rising rate lower than the first rising rate for a second rising period.
    Type: Grant
    Filed: December 5, 2012
    Date of Patent: December 30, 2014
    Assignee: SK Hynix Inc.
    Inventors: Noh Yong Park, Hyung Seok Kim
  • Publication number: 20140376314
    Abstract: An instruction to write to a location in the Flash memory is received. It is determining if the Flash memory exposes a level placement setting associated with defining what voltage range corresponds to what level. In the event it is determined that the Flash memory exposes a level placement setting, an accurate coarse write is performed on the location, including by configuring the level placement setting to be a first value, and after the accurate coarse write is performed on the location, a fine write is performed on the location, including by configuring the level placement setting to be a second value, in response to receiving the instruction.
    Type: Application
    Filed: September 5, 2014
    Publication date: December 25, 2014
    Inventors: Meng-Kun Lee, Yingquan Wu
  • Patent number: 8917550
    Abstract: Apparatus configured to perform a programming operation on a row of memory cells in response to original data, configured to perform a comparison of verified data of the row of memory cells to the original data following success of the programming of the row of memory cells, and further configured to perform a post-programming program operation on the row of memory cells if the verified data is different from the original data.
    Type: Grant
    Filed: June 11, 2012
    Date of Patent: December 23, 2014
    Assignee: Micron Technology, Inc.
    Inventor: June Lee
  • Publication number: 20140369131
    Abstract: A semiconductor device is operated by, inter alia: programming selected memory cells by applying a first program voltage which is increased by a first step voltage to a selected word line and by applying a first pass voltage having a constant level to unselected word lines, and when a voltage difference between the first program voltage and the first pass voltage reaches a predetermined voltage difference, programming the selected memory cells by applying a second program voltage which is increased by a second step voltage lower than the first step voltage to the selected word line and by applying a second pass voltage which is increased in proportion to the second program voltage to first unselected word lines adjacent to the selected word line among the unselected word lines.
    Type: Application
    Filed: August 29, 2014
    Publication date: December 18, 2014
    Inventor: Seiichi ARITOME
  • Patent number: 8913428
    Abstract: A system and methods for programming a set of data onto non-volatile memory elements, maintaining copies of the data pages to be programmed, as well as surrounding data pages, internally or externally to the memory circuit, verifying programming correctness after programming, and upon discovering programming error, recovering the safe copies of the corrupted data to be reprogrammed in alternative non-volatile memory elements. Additionally, a system and methods for programming one or more sets of data across multiple die of a non-volatile memory system, combining data pages across the multiple die by means such as the XOR operation prior to programming the one or more sets of data, employing various methods to determine the correctness of programming, and upon identifying data corruption, recovering safe copies of data pages by means such as XOR operation to reprogram the pages in an alternate location on the non-volatile memory system.
    Type: Grant
    Filed: January 25, 2013
    Date of Patent: December 16, 2014
    Assignee: SanDisk Technologies Inc.
    Inventor: Yan Li
  • Patent number: 8908441
    Abstract: Memory cells which have read noise are identified during a programming pass and an amount of programming is increased for noisy memory cells compared to non-noisy cells. The read noise is indicated by a decrease in the threshold voltage of a cell when the cell is repeatedly read. In one approach, during the programming pass, a cell enters a temporary lockout state when it passes a first verify test and is subject to one or more additional verify tests. Data is stored to identify the cell as a noisy cell or a non-noisy cell based on the one or more additional verify tests. Or, the cells are subject to the one or more additional verify tests at the end of the programming pass. In a subsequent programming pass, the noisy cell is programmed using a stricter verify condition. Or, the noisy cell is kept in an erased state.
    Type: Grant
    Filed: October 15, 2013
    Date of Patent: December 9, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Ken Oowada, Genki Sano, Masaaki Higashitani
  • Patent number: 8908435
    Abstract: An erase process for a 3D stacked memory device controls a drain-side select gate (SGD) and a source-side select gate (SGS) of a NAND string. In one approach, SGD and SGS are driven to provide a predictable drain-to-gate voltage across the select gates while an erase voltage is applied to a bit line or source line. A more consistent gate-induced drain leakage (GIDL) at the select gates can be generated to charge up the body of the NAND string. Further, the select gate voltage can be stepped up with the erase voltage to avoid an excessive drain-to-gate voltage across the select gates which causes degradation. The step up in the select gate voltage can begin with the first erase-verify iteration of an erase operation, or at a predetermined or adaptively determined erase-verify iteration, such as based on a number of program-erase cycles.
    Type: Grant
    Filed: December 21, 2011
    Date of Patent: December 9, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Haibo Li, Xiying Costa, Chenfeng Zhang
  • Patent number: 8902665
    Abstract: A solid state storage system includes a memory area having a plurality of pages and is capable of storing program information about each page. The memory area stores the number of pulse counts applied to each page. A main memory controller receives the program information from the memory area and determines whether to program pages according to the program information. The main memory controller determines whether the program information for a page is at a predetermined amount and if the corresponding page should be programmed again or not.
    Type: Grant
    Filed: November 15, 2011
    Date of Patent: December 2, 2014
    Assignee: SK Hynix Inc.
    Inventors: Jin-Chul Kim, Young-Kyun Shin
  • Patent number: 8902667
    Abstract: Non-volatile memory (NVM) systems and related methods adjust program/erase bias conditions for non-volatile memory (NVM) cells to improve performance and product lifetime of NVM systems. System embodiments include integrated NVM systems having an NVM controller, a bias voltage generator, and an NVM cell array. Further, the NVM systems can store performance degradation information and program/erase bias condition information within storage circuitry. The disclosed embodiments adjust program/erase bias conditions for the NVM cells based upon performance degradation determinations, for example, temperature-based performance degradation determinations and interim verify based performance degradation determinations.
    Type: Grant
    Filed: July 25, 2012
    Date of Patent: December 2, 2014
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Fuchen Mu, Yanzhuo Wang, Chen He, Richard K. Eguchi
  • Patent number: 8902656
    Abstract: An integrated circuit device comprises a semiconductor substrate, a first memory block on the substrate comprising NAND memory cells, a second memory block on the substrate comprising NAND memory cells, and controller circuitry. The first and second memory blocks are configurable to store data for a first pattern of data usage in response to a first operation algorithm to read, program and erase data, and for a second pattern of data usage in response to a second operation algorithm to read, program and erase data, respectively. The controller circuitry is coupled to the first and second memory blocks, and is configured to execute the first and second operation algorithms, wherein a word line pass voltage for read operations applied in the first operation algorithm is at a lower voltage level than a second word line pass voltage for read operations applied in the second operation algorithm.
    Type: Grant
    Filed: January 25, 2013
    Date of Patent: December 2, 2014
    Assignee: Macronix International Co., Ltd.
    Inventors: Tzung-Shen Chen, Shuo-Nan Hong, Yi-Ching Liu, Chun-Hsiung Hung
  • Patent number: 8902668
    Abstract: Memory cells which have read noise are identified during a programming pass and an amount of programming is increased for noisy memory cells compared to non-noisy cells. The read noise is indicated by a decrease in the threshold voltage of a cell when the cell is repeatedly read. During the programming pass, a cell enters a temporary lockout state when it passes a first verify test. In this state, the cell is subject to one or more additional verify tests. If the one or more additional verify tests indicate that the threshold voltage of a cell has decreased, the cell is noisy and is soft programmed before being permanently locked out. In contrast, programming of a non-noisy cell is concluded after the first verify test without further programming.
    Type: Grant
    Filed: October 15, 2013
    Date of Patent: December 2, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Ken Oowada, Genki Sano, Masaaki Higashitani
  • Publication number: 20140347937
    Abstract: A semiconductor device includes a memory block coupled to word lines and configured to a memory cell including a floating gate, an inter-poly dielectric and a control gate and a peripheral circuit configured to perform an erase loop operation, a program loop operation an electron injection operation of the memory cell, the electron injection operation trapping electrons in the inter-poly dielectric.
    Type: Application
    Filed: September 30, 2013
    Publication date: November 27, 2014
    Applicant: SK Hynix Inc.
    Inventor: Hee Youl LEE
  • Patent number: 8897069
    Abstract: A semiconductor memory device of the present invention includes a memory cell array configured to include a sensing circuit configured to perform program verifying of the page buffer group selected by the select signal, and configured to output a pass/fail signal corresponding to the page buffer group, a verifying result signal generation section configured to output one or more of a first verifying signal and a second verifying signal in accordance with pass or fail of the program for total page buffer groups by using the pass/fail signal, and a control circuit configured to output the select signals to verify the program after the program is performed, and control operation of the program in response to an output signal of the verifying result signal generation section.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: November 25, 2014
    Assignee: SK Hynix Inc.
    Inventor: Jea Won Choi
  • Patent number: 8897075
    Abstract: A semiconductor memory device and a method of programming the same are provided which can improve the program accuracy by classifying cells depending on a program status of memory cells during a program operation to control a bit line program voltage. The method comprises classifying memory cells to be programmed based on program characteristics of the memory cells and sequentially providing word line program voltages having increasing voltage levels and bit line program voltages having decreasing voltage levels to the classified memory cells in a program operation, wherein differently classified two memory cells receive different bit line program voltages, respectively.
    Type: Grant
    Filed: April 23, 2012
    Date of Patent: November 25, 2014
    Assignee: SK Hynix Inc.
    Inventor: Jea Won Choi
  • Patent number: 8891299
    Abstract: A method for performing a programming operation to a first memory bit and a second memory bit of a device is described. The method includes applying a pulse train voltage to a metal gate of the device and grounding a substrate of the device. By floating/grounding a drain of the device and/or by floating/grounding the source of the device, the first memory and the second memory bit are programmed. The pulse train voltage includes 10 to 1000 pulses. One pulse includes a peak voltage and a base voltage. The peak voltage ranges from 0.5 V to 10 V. A duration of the peak voltage ranges from 1 nanosecond to 1 millisecond. The base voltage is 0 V. A duration of the base voltage ranges from 1 nanosecond to 1 millisecond.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: November 18, 2014
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Ting-Chang Chang, Chih-Hao Dai, Fu-Yen Jian, Wen-Hung Lo, Shih-Chieh Chang, Ying-Lang Wang
  • Patent number: 8891311
    Abstract: A program method of a semiconductor memory device includes performing a least significant bit (LSB) program operation for target LSB program cells of a selected page, increasing the threshold voltages of target most significant bit (MSB) program cells of the selected page before performing an MSB operation for the target MSB program cells, and performing the MSB program operation for the target MSB program cells after the increasing of the threshold voltages of the target MSB program cells.
    Type: Grant
    Filed: November 29, 2011
    Date of Patent: November 18, 2014
    Assignee: Hynix Semiconductor Inc.
    Inventor: Seok Jin Joo
  • Patent number: 8891308
    Abstract: Techniques are provided for erasing memory cells in a 3D stacked non-volatile memory device in a way which avoids prolonging erase time as the erase speed deceases due to the accumulation of program-erase cycles. In particular, a step size for erase pulses can be set which is a function of the number of program-erase cycles, e.g., as indicated by a count of program-erase cycles, a loop count during programming which is a function of programming speed, or an initial program voltage which is a function of programming speed. Further, the erase operation can account for different erase speeds of memory cells in different word line layers.
    Type: Grant
    Filed: September 11, 2013
    Date of Patent: November 18, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Wendy Ou, Man L Mui, Yingda Dong, Masaaki Higashitani
  • Patent number: 8891314
    Abstract: A semiconductor memory device and the operating method thereof use a low pass voltage to boost a channel of unselected cell strings during a program operation, and boost the channel of the cell string by using the GIDL phenomenon, thereby reducing a disturbance influence on the memory cells connected to the unselected cell strings due to a high pass voltage.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: November 18, 2014
    Assignee: SK Hynix Inc.
    Inventor: Kyoung Jin Park
  • Patent number: 8885420
    Abstract: Techniques are disclosed herein for erasing non-volatile storage elements. A sequence of increasing erase voltages may be applied to a substrate. The select line may be floated and many of the word lines may be held at a low voltage (e.g., close to 0V). However, the voltage applied to an edge word may be increased in magnitude relative to a previous voltage applied to the edge word line for at least a portion of the sequence of erase voltages. The edge word line could be the word line that is immediately adjacent to the select line. The increasing voltage applied to the edge word line may prevent or reduce damage to oxides between the select line and edge word line. It may also help to regulate the e-field across a tunnel oxide of memory cells on the edge word line.
    Type: Grant
    Filed: January 2, 2013
    Date of Patent: November 11, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Ken Oowada, Deepanshu Dutta
  • Patent number: 8885406
    Abstract: A memory device includes: a plurality of nonvolatile memory sections configured to allow one memory cell to record data of a plurality of bits, and to include a corresponding number of pages to the plurality of bits in accordance with a plurality of the memory cells as a write control unit; and a control section configured to control writing and reading data to and from the plurality of nonvolatile memory sections, wherein among the plurality of nonvolatile memory sections, if data is written into one of the nonvolatile memory sections, the data is written for each page in sequence from a low-order page to a high-order page, and when the data is written into the low-order page, control is performed such that the data to be written into the low-order page is written into any area of the other of the nonvolatile memory sections at same timing.
    Type: Grant
    Filed: April 19, 2013
    Date of Patent: November 11, 2014
    Assignee: Sony Corporation
    Inventors: Yuto Hosogaya, Shingo Aso
  • Patent number: 8885415
    Abstract: A system including a read module to perform a first read operation to determine a state of a memory cell, and in response to a first failure to decode data read from the memory cell, perform second and third read operations to determine the state of the memory cell. The memory cell has first and second threshold voltages when programmed to first and second states, respectively. A shift detection module detects, in response to a second failure to decode data read from the memory cell in the second and third read operations, a shift in a distribution of at least one of the first and second threshold voltages. A binning module divides the distribution into a plurality of bins. A log-likelihood ratio (LLR) module generates LLRs for the plurality of bins based on a variance of the distribution and adjusts the LLRs based on an amount of the shift.
    Type: Grant
    Filed: September 9, 2013
    Date of Patent: November 11, 2014
    Assignee: Marvell World Trade Ltd.
    Inventors: Shashi Kiran Chilappagari, Xueshi Yang
  • Patent number: 8885412
    Abstract: An erase process for a 3D stacked memory device controls a drain-side select gate (SGD) and a source-side select gate (SGS) of a NAND string. In one approach, SGD and SGS are driven to provide a predictable drain-to-gate voltage across the select gates while an erase voltage is applied to a bit line or source line. A more consistent gate-induced drain leakage (GIDL) at the select gates can be generated to charge up the body of the NAND string. Further, the select gate voltage can be stepped up with the erase voltage to avoid an excessive drain-to-gate voltage across the select gates which causes degradation. The step up in the select gate voltage can begin with the first erase-verify iteration of an erase operation, or at a predetermined or adaptively determined erase-verify iteration, such as based on a number of program-erase cycles.
    Type: Grant
    Filed: April 16, 2014
    Date of Patent: November 11, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Haibo Li, Xiying Costa, Chenfeng Zhang