Micron Technology Incorporated

Stmicroelectronics Gmbh

Patrick Robert Khayat

Sivagnanam Parthasarathy

Mustafa Nazmi Kaynak

James Fitzpatrick

Abdelhakim Alhussien

AbdelHakim S Alhussien

Vamsi Pavan Rayaprolu

Nicholas Julian Richardson

Kishore Kumar Muchherla

Sampath K Ratnam

Violante Moschiano

Jeffrey S McNeil, Jr

Robert B Eisenhuth

Steven Michael Kientz

William Henry Radke

Larry Joseph Koudele

Michael Sheperek

Zhenlei Shen

Alessandro Risso

Zixiang Loh

Aaron S Yip

Mark Alan Helm

Eric N Lee

Shane G Nowell

Sundararajan Sankaranarayanan

Jiangang Wu

Akira Goda

Jeremy Binfet

Nagendra Prasad Ganesh Rao

Ka Leung Ling

Shantilal Doru

Jung Sheng Hoei

Dung Viet Nguyen

Christopher M Smitchger

Sead Zildzic

Thomas Herbert Lentz

Larry K Koudele

Hyung Seok Kim

Embodiments disclosed can include selecting a target read window budget (RWB) increase and identifying a set of aggressor memory cells. They can also include generating a list of programming level states for the set of aggressor memory cells and identifying, in the list, an entry associated with a maximum RWB increase that is greater than or equal to the target RWB increase. They can further include responsive to identifying the entry with the total number of bits associated with a maximum RWB increase that is greater than or equal to the target RWB increase, modifying a parameter of the memory access operation with the adjustment associated with the identified entry.

Managing compensation for charge coupling and lateral migration in memory devices

Described are systems and methods for validating read level voltage in memory devices. An example memory device comprises: a memory array comprising a plurality of memory cells electrically coupled to a plurality of wordlines; and a controller coupled to the memory array, the controller to perform operations comprising: causing a read level voltage to be applied to a specified wordline of the plurality of wordlines; receiving an actual bit count reflecting a number of memory cells that have their respective threshold voltages below the read level voltage; and responsive to determining that a difference of an expected bit count and the actual bit count exceeds a predetermined threshold value, adjusting the read level voltage.

Validating read level voltage in memory devices

A memory device to manage the assignment of offset voltages for read operations, and to adjust read voltages using the offset voltages. The offset voltages are dynamically adjusted by a controller during operation of the memory device in response to read errors. In one approach, a first bin of offset voltages is assigned to a first region of a storage media. The first offset voltages are used to adjust read voltages for reading a page of first memory cells in the first region. The controller determines that at least one error has occurred in reading the page. In response to determining the error, the controller determines second offset voltages that can be used to read the first memory cell without causing a read error. Based on the second offset voltages, the controller identifies third offset voltages for assigning to the first region. The third offset voltages are used for adjusting read voltages for subsequent reads of pages in the first region. The third offset voltages can be assigned from an existing offset voltage bin, or a new offset voltage bin can be generated for the assignment.

Dynamic adjustment of offset voltages for reading memory cells in a memory device

Systems and methods are disclosed including a memory device and a processing device operatively coupled to the memory device. The processing device can perform operations comprising performing a data integrity check on a source set of memory cells, configured to store a first number of bits per memory cell, to obtain a data integrity metric value; responsive to determining that the data integrity metric value satisfies the threshold criterion, performing an error handling operation on the data stored on the source set of memory cells to generate corrected data; and causing the memory device to copy data the corrected data to a destination set of memory cells of the memory device, wherein the destination set of memory cells are configured to store a second number of bits per memory cell, wherein the second number of bits per memory cells is greater than the first number of bits per memory cell.

Memory compaction management in memory devices

A system can include a memory device and a processing device, operatively coupled with the memory device, to perform operations including reading a first copy of data stored in a first set of memory cells comprising a first memory cell, determining whether a threshold voltage of the first memory cell is within a first range of threshold voltages, responsive to determining that the threshold voltage of the first memory cell is within the first range of threshold voltages, reading a second copy of the data stored in a second set of memory cells comprising a second memory cell, determining whether a threshold voltage of the second memory cell is within a second range of threshold voltages, and responsive to determining that the threshold voltage of the second memory cell is outside the second range, using the second copy of the data.

Using duplicate data for improving error correction capability

A processing device in a memory sub-system monitors a temperature associated with a block of a memory device, the block comprising a plurality of wordlines. The processing device further determines a first amount of time between when memory cells associated with a first wordline of the plurality of wordlines of the block were written and when memory cells associated with a last wordline of the plurality of wordlines of the block were written. That first amount of time is normalized according to the temperature associated with the block. The processing device further determines, based at last in part on the first amount of time and on an associated scaling factor, an estimate of when the block will reach a uniform charge loss state.

Temperature-compensated time estimate for a block to reach a uniform charge loss state

A processing device in a memory sub-system detects an occurrence of a triggering event, determines respective levels of charge loss associated with a first representative wordline of a block of a memory device and with a second representative wordline of the block of the memory device, and determines whether a difference between the respective levels of charge loss satisfies a threshold criterion. Responsive to determining that the difference between the respective levels of charge loss satisfies the threshold criterion, the processing device further determines that the block is in a uniform charge loss state.

Measurement of representative charge loss in a block to determine charge loss state

A memory device to determine a voltage optimized to read a group of memory cells. In response to a command, the memory device reads the group of memory cells at a plurality of test voltages to determine a set of signal and noise characteristics of the group of memory cells. The memory device determines or recognizes a shape of a distribution of the signal and noise characteristics over the plurality of test voltages. Based on the shape, the memory device selects an operation in determining an optimized read voltage of the group of memory cells.

Determine optimized read voltage via identification of distribution shape of signal and noise characteristics

Embodiments disclosed can include determining, for each memory cell connected to each wordline, a respective value of a metric that reflects a sensitivity of a threshold voltage associated with the memory cell to a change in a threshold voltage of an adjacent cell and determining, for each wordline, based on the determined sensitivity for each memory cell, a respective aggregate measure of adjacent cell dependence. They can further include comparing the determined aggregate measure of adjacent cell dependence to a threshold dependence value. They can also include identifying a first wordline group having wordlines with high adjacent cell dependence and a second wordline group having wordlines with low adjacent cell dependence and storing a record referencing the wordlines of the second wordline group, the record indicating a corresponding location on the die of the memory device.

Managing error compensation using charge coupling and lateral migration sensitivity

Embodiments disclosed can include determining, for a wordline of the plurality of wordlines, a respective value of a sensitivity metric that reflects a sensitivity of a threshold voltage of a memory cell associated with the wordline to a change in a threshold voltage of an adjacent memory cell. Embodiments can also include determining, for the wordline, that the respective value of the sensitivity metric satisfies a threshold criterion. Embodiments can further include responsive to determining that the respective value of the sensitivity metric satisfies the threshold criterion, associating the wordline with a first wordline group, wherein the first wordline group comprises one or more wordlines, and wherein each wordline of the one or more wordlines is associated with a respective value of the sensitivity metric that satisfies the threshold criterion. Embodiments can include performing, on a specified memory cell connected to the wordline associated with the first wordline group, a compensatory operation.

Managing compensation for cell-to-cell coupling and lateral migration in memory devices based on a sensitivity metric

A method includes receiving, by control logic of a memory device, a copyback clear command from a processing device; causing, in response to the copyback clear command, a page buffer to perform a dual-strobe read operation on first memory cells configured as single-level cells, the dual-strobe read operation including a soft strobe at a first threshold voltage and a hard strobe at a second threshold voltage that are sensed between threshold voltage distributions of the first memory cells; causing the page buffer to determine a number of one bit values within the threshold voltage distributions detected in a threshold voltage range between the first/second threshold voltages; and causing, in response to the number of one bit values not satisfying a threshold criterion, a copyback of data in the first memory cells to second memory cells configured as high-level cells without intervention from the processing device.

Copyback clear command for performing a scan and read in a memory device

Embodiments disclosed can include determining, for a wordline of the plurality of wordlines, a target read window budget (RWB) increase, wherein the target RWB increase corresponds to a maximum RWB increase associated with using a different PV voltage offset for each respective programming level of a memory cell. Embodiments can also include segmenting the plurality of wordlines into one or more wordline groups, wherein each wordline group comprises one or more wordlines. Embodiments can further include determining, for each wordline group, a target adjustment to a parameter of a memory access operation that is performed with respect to a memory cell associated with a wordline of the wordline group. Embodiments can include determining an aggregate RWB increase for the block in view of the target adjustment to the parameter of the memory access operation. Embodiments can further include determining that the aggregate RWB increase for the block satisfies a threshold range associated with the target RWB increase. Embodiments can also include modifying the parameter of the memory access operation according to the target adjustment.

Managing compensation for cell-to-cell coupling and lateral migration in memory devices using segmentation

Systems and methods are disclosed including a memory device and a processing device operatively coupled to the memory device. The processing device can perform operations comprising selecting a source set of memory cells of the memory device, performing a data integrity check on the source set of memory cells to obtain a data integrity metric value; responsive to determining that a data integrity metric value satisfies the threshold criterion, performing a first error-handling operation on the data stored on the source set of memory cells; responsive to determining that the first error-handling operation fails to correct the data, performing a second error-handling operation on the data; and responsive to determining that the second error-handling operation corrected the data, causing the memory device to copy the corrected data to a destination set of memory cells of the memory device.

Error-handling management during copyback operations in memory devices

Processing logic in a memory device receives a command to execute a set of read operations having read voltage levels corresponding to a programming distribution associated with the memory device. A set of memory bit counts is determined, where each memory bit count corresponds to a respective bin of a set of bins associated with the multiple read voltage levels of the set of read operations. A valley center bin having a minimum memory bit count of the set of memory bit counts is determined. The processing logic determines that the minimum memory bit count of the valley center bin satisfies a condition and an adjusted read voltage level associated with the valley center bin is identified in response to the condition being satisfied.

Integrated command to calibrate read voltage level

A memory sub-system to track charge loss in memory cells and shifts of voltages optimized to read the memory cells. For example, a memory device can measure signal and noise characteristics of a group of memory cells to calculate an optimized read voltage of the group of memory cells. The memory sub-system having the memory device can determine an amount of charge loss in the group of memory cells, using at least the signal and noise characteristics, the optimized read voltage, and/or the bit error rate of data read using the optimized read voltage. The memory sub-system tracks changes in optimized read voltages of memory cells in the memory device based on the amount of charge loss.

Growing community of inventors

San Diego, CA, United States of America

Patrick Robert Khayat