Sandisk Technologies Inc.

Western Digital Technologies, Inc.

Longju Liu

Jiahui Yuan

Sarath Chandran Puthenthermadam

Yi Song

Parth Amin

Sujjatul Islam

An apparatus is provided that includes a control circuit coupled to a plurality of non-volatile memory cells. The control circuit is configured to perform a program-verify iteration on a first set of the non-volatile memory cells in a plurality of program loops, determine that the first set of the non-volatile memory cells passes verification to a particular programmed state in a first number of program loops, determine a first voltage based on the first number of program loops, add an adaptive voltage offset to the first voltage to obtain a second voltage, and program a second set of the non-volatile memory cells in a plurality of program loops using the second voltage. The adaptive voltage offset varies as a function of temperature.

Apparatus and methods for smart verify with adaptive voltage offset

A memory system performs an erase process for the non-volatile memory cells including performing erase verify for the non-volatile memory cells. The erase verify comprises comparing threshold voltages of the non-volatile memory cells to an erase verify reference voltage and determining whether an amount of the non-volatile memory cells having a threshold voltage greater than the erase verify reference voltage is less than an allowed bit count. During the erase process, the system compares threshold voltages of the non-volatile memory cells to an intermediate reference voltage that is greater than the erase verify reference voltage and determines an amount of non-volatile memory cells having threshold voltages greater than the intermediate reference voltage. The Allowed Bit Count is increased (during the erase process) by the amount of non-volatile memory cells having threshold voltages greater than the intermediate reference voltage.

Non-volatile memory with adapting erase process

Technology is disclosed herein for detecting grown bad blocks in a non-volatile storage system. A stress test may accelerate stressful conditions on the memory cells and thereby provide for early detection of grown bad blocks. The stress test may include applying a program voltage to a selected word line and a stress voltage that is less than a nominal boosting voltage to a word line adjacent one side of the selected word line. The combination of the program voltage and the stress voltage may generate an e-field that is stronger than an e-field that would be generated in a normal program operation, thereby accelerating the stress on the memory cells. The stress test mat further include programming all of the memory cells to a relatively high threshold voltage, which may create additional stress on the memory cells.

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Fremont, CA, United States of America

Longju Liu