Patents by Inventor Jeffrey W. Lutze

Jeffrey W. Lutze 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: 8743606
    Abstract: In a non-volatile memory system, a programming operation applies programming pulses to a target word line, determines when a specified number of the non-volatile storage elements reach a defined verify level, and counts a specified number of the programming pulses after the specified number of the non-volatile storage elements reach the defined verify level. Upon completion of the counting, faster-programming storage elements are distinguished from slower-programming storage elements. Programming continues for of at least some of the faster-programming non-volatile storage elements, with an associated programming speed-based slow down measure imposed thereon, and for at least some of the slower-programming non-volatile storage elements without imposing a programming speed-based slow down measure.
    Type: Grant
    Filed: August 19, 2013
    Date of Patent: June 3, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W Lutze
  • Patent number: 8743624
    Abstract: A non-volatile storage system performs programming for a plurality of non-volatile storage elements and selectively performs re-erasing of at least a subset of the non-volatile storage elements that were supposed to remain erased, without intentionally erasing programmed data.
    Type: Grant
    Filed: April 25, 2012
    Date of Patent: June 3, 2014
    Assignee: Sandisk Technologies, Inc.
    Inventors: Jeffrey W. Lutze, Yan Li
  • Patent number: 8614915
    Abstract: A plurality of non-volatile storage elements on a common active layer are offset from neighbor non-volatile storage elements. This offsetting of non-volatile storage elements helps reduce interference from neighbor non-volatile storage elements. A method of manufacture is also described for fabricating the offset non-volatile storage elements.
    Type: Grant
    Filed: June 24, 2010
    Date of Patent: December 24, 2013
    Assignee: Sandisk Technologies Inc.
    Inventors: Jeffrey W. Lutze, Dana Lee
  • Patent number: 8611148
    Abstract: In a programming operation, selected storage elements on a selected word line are programmed while unselected storage elements on the selected word line are inhibited from programming by channel boosting. To provide a sufficient but not excessive level of boosting, the amount of boosting can be set based on a data state of the unselected storage element. A greater amount of boosting can be provided for a lower data state which represents a lower threshold voltage and hence is more vulnerable to program disturb. A common boosting scheme can be used for groups of multiple data states. The amount of boosting can be set by adjusting the timing and magnitude of voltages used for a channel pre-charge operation and for pass voltages which are applied to word lines. In one approach, stepped pass voltages on unselected word lines can be used to adjust boosting for channels with selected data states.
    Type: Grant
    Filed: March 23, 2012
    Date of Patent: December 17, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W Lutze, Grishma Shah
  • Publication number: 20130329493
    Abstract: In a non-volatile memory system, a programming operation is performed in which faster-programming storage elements are distinguished from slower-programming storage elements. In one approach, the distinguishing is achieved by applying programming pulses to a target word line, determining when a specified number of the non-volatile storage elements reach a defined verify level, and counting a number of the programming pulses after the specified number of the non-volatile storage elements reach the defined verify level. Upon completion of the counting, the non-volatile storage elements can be read using a read voltage. The storage elements having a threshold voltage above or below the read voltage are the faster- or slower-programming storage elements, respectively. The number of the programming pulses can be set based on a natural threshold voltage distribution of the non-volatile storage elements.
    Type: Application
    Filed: August 19, 2013
    Publication date: December 12, 2013
    Applicant: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W Lutze
  • Patent number: 8542535
    Abstract: A technique for erasing a non-volatile memory applies a p-well voltage to a substrate and drives select gate voltages to accurately control the select gate voltage to improve write-erase endurance. Source and drain side select gates of a NAND string are driven at levels to optimize endurance. In one approach, the select gates are driven at specific levels throughout an erase operation, in concert with the p-well voltage.
    Type: Grant
    Filed: July 13, 2011
    Date of Patent: September 24, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W Lutze
  • Patent number: 8537611
    Abstract: In a non-volatile memory system, a multi-phase programming operation is performed. In one phase, faster-programming storage elements have a higher bit line bias (Vbl) than slower-programming storage elements. In a next phase, the faster- and slower-programming storage elements have a lower Vbl. Further, a drain-side select gate voltage (Vsgd) can be adjusted in the different programming phases to accommodate the different Vbl levels. A higher Vsgd can be used in the one phase when Vbl is higher to avoid unnecessary stress on the SGD transistor and reduce power consumption. Vsgd can be reduced in the next phase when the lower Vbl is used. The higher Vbl is a slowdown measure which can be applied when the Vth of a storage element is between lower and upper verify levels of target data states, or throughout a programming phase.
    Type: Grant
    Filed: June 14, 2012
    Date of Patent: September 17, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W Lutze
  • Patent number: 8520448
    Abstract: A non-volatile storage system reduces program disturb in a set of non-volatile storage elements by programming using selected bit line patterns which increase the clamped boosting potential of an inhibited channel to avoid program disturb. First, second and third sets of non-volatile storage elements are programmed in separate sequences, one after another, so that all program-verify operations occur for the first set, then for the second set, and then for the third set. Each non-volatile storage element in a set is separated from the next closest non-volatile storage element in the set at least two other non-volatile storage elements in the set.
    Type: Grant
    Filed: April 10, 2013
    Date of Patent: August 27, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Jeffrey W Lutze, Deepanshu Dutta
  • Patent number: 8462547
    Abstract: A plurality of non-volatile storage elements on a common active layer are offset from neighbor non-volatile storage elements. This offsetting of non-volatile storage elements helps reduce interference from neighbor non-volatile storage elements. A method of manufacture is also described for fabricating the offset non-volatile storage elements.
    Type: Grant
    Filed: June 24, 2010
    Date of Patent: June 11, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Jeffrey W. Lutze, Dana Lee
  • Patent number: 8451667
    Abstract: A non-volatile storage system reduces program disturb in a set of non-volatile storage elements by programming using selected bit line patterns which increase the clamped boosting potential of an inhibited channel to avoid program disturb. Alternate pairs of adjacent bit lines are grouped into first and second sets. Non-volatile storage elements of the first set of pairs are subject to program pulses and verify operations in each of a first number of iterations, after which non-volatile storage elements of the second set of pairs is subject to program pulses and verify operations in each of a second number of iterations.
    Type: Grant
    Filed: January 27, 2012
    Date of Patent: May 28, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Jeffrey W Lutze, Deepanshu Dutta
  • Patent number: 8400836
    Abstract: A set non-volatile storage elements are subjected to a programming process in order to store a set of data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target condition to store the appropriate data. Decisions about whether to continue programming or whether the programming is successful are made based on whether overlapping groups of the non-volatile storage elements have less than a threshold number of non-volatile storage elements that are not properly programmed.
    Type: Grant
    Filed: February 25, 2011
    Date of Patent: March 19, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Yan Li, Teruhiko Kamei, Jeffrey W. Lutze
  • Patent number: 8385132
    Abstract: In a non-volatile storage system, capacitive coupling effects are reduced by reducing the probability that adjacent storage elements reach the lockout condition at close to the same program pulse. A slow down measure such as an elevated bit line voltage is applied to the storage elements of a word line which are associated with odd-numbered bit lines, but not to the storage elements associated with even-numbered bit lines. The elevated bit line voltage is applied over a range of program pulses, then stepped down to ground over one or more program pulses. The range of programming pulses over which the slow down measure is applied, can be fixed or determined adaptively. A program pulse increment can be dropped, then increased, when the bit line voltage is stepped down. Storage elements which are programmed to a highest target data state can be excluded from the slow down measure.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: February 26, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W. Lutze
  • Patent number: 8369149
    Abstract: In a programming operation, selected storage elements which reach a lockout condition are subject to reduced channel boosting in a program portion of the next program-verify iteration, to reduce coupling effects on the storage elements which continue to be programmed. In subsequent program-verify iterations, the locked out storage elements are subject to full channel boosting. Or, the boosting can be stepped up over multiple program-verify iterations after lockout. The amount of channel boosting can be set by adjusting the timing of a channel pre-charge operation and by stepping up pass voltages which are applied to unselected word lines. The reduced channel boosting can be implemented for a range of program-verify iterations where the lockout condition is most likely to be first reached, for one or more target data states.
    Type: Grant
    Filed: September 30, 2010
    Date of Patent: February 5, 2013
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W. Lutze, Henry Chin
  • Patent number: 8310870
    Abstract: In a non-volatile memory system, a programming speed-based slow down measure such as a raised bit line is applied to the faster-programming storage elements. A multi-phase programming operation which uses a back-and-forth word line order is performed in which programming speed data is stored in latches in one programming phase and read from the latches for use in a subsequent programming phase of a given word line. The faster and slower-programming storage elements can be distinguished by detecting when a number of storage elements reach a specified verify level, counting an additional number of program pulses which is set based on a natural threshold voltage distribution of the storage elements, and subsequently performing a read operation that separates the faster and slower programming storage elements. A drain-side select gate voltage can be adjusted in different programming phases to accommodate different bit line bias levels.
    Type: Grant
    Filed: August 3, 2010
    Date of Patent: November 13, 2012
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W. Lutze
  • Patent number: 8288225
    Abstract: A nonvolatile memory array includes floating gates that have an inverted-T shape in cross section along a plane that is perpendicular to the direction along which floating cells are connected together to form a string. Adjacent strings are isolated by shallow trench isolation structures.
    Type: Grant
    Filed: January 20, 2011
    Date of Patent: October 16, 2012
    Assignee: SanDisk Technologies Inc.
    Inventors: Henry Chien, George Matamis, Tuan Pham, Masaaki Higashitani, Hidetaka Horiuchi, Jeffrey W. Lutze, Nima Mokhlesi, Yupin Kawing Fong
  • Publication number: 20120250418
    Abstract: In a non-volatile memory system, a multi-phase programming operation is performed in which a drain-side select gate voltage (Vsgd) can be adjusted in different programming phases to accommodate different bit line bias (Vbl) levels. A higher Vbl can be used when Vsgd is higher to avoid unnecessary stress on the SGD transistor and reduce power consumption. For example, Vsgd can be higher in an earlier program phase than in a later program phase. The higher Vbl, which is not based on programming speed, can be is applied when the Vth of a storage element is between lower and upper verify levels of target data states, or throughout a programming phase, or at other times. The higher Vbl is an additional slow down measure which can be implemented in addition to a programming speed-based slow down measure such as a further raised Vbl which is applied to faster-programming storage elements.
    Type: Application
    Filed: June 14, 2012
    Publication date: October 4, 2012
    Inventors: Deepanshu Dutta, Jeffrey W Lutze
  • Patent number: 8274838
    Abstract: Threshold voltage distributions in a non-volatile memory device are narrowed, and/or programming time is reduced, using a programming technique in which the bit line voltage for storage elements having a target data state is stepped up, in lock step with a step up in the program voltage. The step up in the bit line voltage is performed at different times in the programming pass, for different subsets of storage elements, according to their target data state. The start and stop of the step up in the bit line voltage can be set based on a fixed program pulse number, or adaptive based on a programming progress. Variations include using a fixed bit line step, a varying bit line step, a data state-dependent bit line step, an option to not step up the bit line for one or more data states and an option to add an additional bit line bias.
    Type: Grant
    Filed: July 19, 2010
    Date of Patent: September 25, 2012
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W. Lutze
  • Patent number: 8248850
    Abstract: An error detection and data recovery operation for a non-volatile memory system. Even after a programming operation for a set of storage elements is successfully completed, the data of some storage elements may be corrupted. For example, erased state storage element may be disturbed by programming of other storage elements. To allow recovery of data in such situations, associated data latches can be configured to allow the erased state storage elements to be distinguished from other data states once programming is completed. Furthermore, a single read operation can be performed after programming is completed. Logical operations are performed using results from the read operation, and values in the data latches, to identify erased state storage elements which have strayed to another data state. If the number of errors exceeds a threshold, a full recovery operation is initiated in which read operations are performed for the remaining states.
    Type: Grant
    Filed: January 28, 2010
    Date of Patent: August 21, 2012
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W. Lutze, Yan Li
  • Patent number: RE45520
    Abstract: In a programming operation, selected storage elements on a selected word line are programmed while unselected storage elements on the selected word line are inhibited from programming by channel boosting. To provide a sufficient but not excessive level of boosting, the amount of boosting can be set based on a data state of the unselected storage element. A greater amount of boosting can be provided for a lower data state which represents a lower threshold voltage and hence is more vulnerable to program disturb. A common boosting scheme can be used for groups of multiple data states. The amount of boosting can be set by adjusting the timing and magnitude of voltages used for a channel pre-charge operation and for pass voltages which are applied to word lines. In one approach, stepped pass voltages on unselected word lines can be used to adjust boosting for channels with selected data states.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: May 19, 2015
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepanshu Dutta, Jeffrey W Lutze, Grishma Shah
  • Patent number: RE45699
    Abstract: A non-volatile storage system performs programming for a plurality of non-volatile storage elements and selectively performs re-erasing of at least a subset of the non-volatile storage elements that were supposed to remain erased, without intentionally erasing programmed data.
    Type: Grant
    Filed: May 29, 2014
    Date of Patent: September 29, 2015
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Jeffrey W. Lutze, Yan Li