Sandisk Technologies Inc.

Sandisk Technoloiges LLC

Lito De La Rama

Xiaochen Zhu

Jiahui Yuan

Yi Song

Ramy Nashed Bassely Said

Xiang Yang

Jiacen Guo

Brian Murphy

Yihang Liu

Feng Gao

Heguang Li

Suanbin Loh

Yuanyuan Wu

Jimmy Yeh

Norman Lay

A non-volatile memory system tests for a voltage leak in any of multiple planes using a voltage being ramped up on selected word lines in the multiple planes. If no voltage leak is detected, then the system concurrently programs data into memory cells connected to the selected word lines in the multiple planes. If a voltage leak is detected in any of the planes, then the system separately tests each plane for the voltage leak at its respective selected word line in order to determine which plane is the source of the voltage leak, and then concurrently programs data into memory cells connected to the selected word lines in planes without the detected voltage leak while isolating the plane with the detected voltage leak.

Non-volatile memory with neighbor plane program disturb avoidance

A memory device includes a horizontal source layer which is laterally separated into laterally isolated portions located in adjacent memory blocks by a dielectric backside trench fill structure or a source isolation dielectric structure.

Three-dimensional memory device with source line isolation and method of making the same

A rotatable transmission electron microscope (TEM) grid holder includes first and second legs orthogonally positioned with respect to each other. Each clamp holder leg is configured to be received within a hole in a main stage supporting the rotatable TEM grid holder. When the first leg of the clamp holder is affixed within the main stage, the sample has a first orientation with respect to the FIB, and when second leg of the clamp holder is affixed within the main stage, the sample has a second orientation with respect to the FIB, rotated 90° relative to the first orientation. The sample may be rotated back and forth between the first and second orientations multiple times as needed to produce a sample which may be clearly imaged by the TEM system, substantially free of curtaining effects.

Rotatable TEM grid holder for improved FIB thinning process

A non-volatile memory system detects a memory operation failure. In response to the memory operation failure, the system determines whether adjusting an overdrive voltage applied to a word line avoids the memory operation failure. If adjusting the overdrive voltage applied to the word line avoids the memory operation failure, then future memory operations are performed by applying the adjusted overdrive voltage to the word line.

Non-volatile memory with smart control of overdrive voltage

Technology is disclosed herein for early erase termination as a counter-measure for erase disturb. Multiple erase blocks of NAND memory cells are erased in parallel during an erase procedure. Erasing multiple erase blocks in parallel can place considerable strain on the circuitry that generates the erase voltage. If there is significant leakage current in one of the erase blocks the magnitude of the erase voltage for all of the erase blocks may drop. The erase blocks are tested sequentially for leakage current during the first erase loop while the erase voltage is applied to only the erase block under test. If any erase block fails the leakage current test that erase block is removed from the erase procedure. One or more additional erase loops are then performed with only those erase blocks that passed the leakage current test simultaneously receiving an erase voltage, thereby preventing erase disturb with early termination.

NAND early erase termination based on leakage current test

To reduce data disturbs and lower current requirements of a 3D NAND memory die, a multi-block plane of non-volatile memory cells has its source line separated into multiple source line regions by introduction of isolation trenches. The plane structure for the NAND memory is maintained, but is broken into multi-block sub-planes, each with an independently biasable source line.

Non-volatile memory with sub-planes having individually biasable source lines

A non-volatile memory system limits the amount of programming for a first type of group of non-volatile memory cells based on a first parameter such that a maximum number of programming pulses applied to the first type of group of non-volatile memory cells to program to the last data state after the first type of group of non-volatile memory cells completed programming to the other data states is X programming pulses. The non-volatile memory system limits the amount of programming for a second type of group of the non-volatile memory cells based on a second parameter such that a maximum number of programming pulses applied to the second type of group of non-volatile memory cells to program to the last data state after the second type of group of non-volatile memory cells completed programming to the other data states is Y programming pulses.

Non-volatile memory with zoned control for limiting programming for different groups of non-volatile memory cells

An erase process for a group of non-volatile memory cells comprises applying doses of erasing to the group and performing erase verify between pairs of successive doses of erasing. The time needed to complete the erase process can be reduced by optimizing the order of performing erase verify. For example, erase verify can be performed by separately performing erase verify for multiple portions of the group in order from previously determined slowest erasing portion of the group to previously determined fastest erasing portion of the group, and aborting the performing of erase verify prior to completion of erase verify for all of the portions of the group in response to a number erase errors exceeding a limit.

Non-volatile memory with optimized erase verify sequence

To prevent loss of data due to a word line to memory hole short (or another defect), it is proposed to perform an erase process for a plurality of memory cells, detect that a subset of the plurality of memory cells are slow to erase, and prevent successfully programming for at least some of the memory cells that are slow to erase. This technique uses the erase process to predict future word line to memory hole shorts and prevent programming of memory cells predicted to have a future word line to memory hole short so no data will be lost when the short manifests.

Non-volatile memory with short prevention

Technology is disclosed herein for a memory system that compensates for different programming speeds in two sets of memory cells when reading those two sets of memory cells. The memory system programs a group of the memory cells to one or more data states. In one aspect, the memory cells are not verified during programming. The group has a first set of memory cells that program at a first speed and a second set of memory cells that program at a second speed. The memory system reads the first set of the memory cells with a first set of read parameters and reads the second set of the memory cells with a second set of read parameters. The first set of read parameters are different from the second set of read parameters to compensate for the different programming speeds.

Memory cell group read with compensation for different programming speeds

A source side programming method and system are provided. A bad trigger block, of a plurality of blocks of a memory array, may be detected by determining a threshold voltage distribution of a drain side select gate of a block and determining whether the distribution is abnormal. If the distribution is abnormal, the block is a bad trigger block which may cause a failure in another block. IF the block is a bad trigger block, source side programming is performed on at least one word line of the bad trigger block by applying a non-zero voltage to at least one source side word line of the bad trigger block via a source side line.

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San Jose, CA, United States of America

Lito De La Rama