Non-volatile memory cell read failure reduction
AssigneeMicron Technology, Inc.
InventorSeiichi Aritome
Life of this patent
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Abstract
The present disclosure includes various method, device, and system embodiments for reducing non-volatile memory cell read failures. One such method embodiment includes performing a first read operation, using an initial read potential, to determine a state of a selected memory cell in a string of non-volatile memory cells. This method includes determining whether the state of the selected memory cell is an incorrect state by performing a first check using a data checking technique, and if the incorrect state is determined, performing a number of subsequent read operations using read potentials stepped to a higher and a lower read potential to a particular count of read operations.
Claims15
A method for operating a memory system having an array of non-volatile memory cells, comprising:
- performing a first read operation by applying a ground potential to a selected word line of the array and an initial read potential, different than the ground potential, to a number of unselected word lines to determine a current logic state of a group of cells on the selected word line;
- performing a check to determine whether the group of cells includes more than a threshold number of cells having an incorrect logic state after the first read operation;
- when greater than the threshold number of cells of the group has the incorrect logic state, performing at least two subsequent read operations using a read potential different than the initial read potential, wherein the check is performed on the group after each of the at least two subsequent read operations to a particular count of checks.
An electronic system, comprising:
- a processor;
- and
- a memory device coupled to the processor, the memory device comprising:
- at least one array of non-volatile memory cells arranged in rows coupled by word lines and columns coupled by bit lines;
- and
- control circuitry coupled to the array of non-volatile memory cells and configured to execute a method for reading data that includes:
- applying a first potential to a selected word line in the array, the selected word line including a group of cells representing data being read, each of the cells in the group having a state associated therewith;
- applying an initial potential to a number of word lines adjacent the selected word line
- performing a data check to determine whether a cell in the group is in an incorrect state;
- and
- when a cell in the group is in the incorrect state, performing at least two subsequent read operations including a first subsequent read operation using a first stepped potential applied to the number of adjacent word lines that is different than the initial potential and a second subsequent read operation using a second stepped potential applied to the number of adjacent word lines that is different than the second stepped potential, and wherein the data check is performed after each of the at least two subsequent read operations to a particular count of data checks.
Dependencies are inferred from the claim text.