Method of writing data to a semiconductor memory device
AssigneeKabushiki Kaisha Toshiba
InventorsMasaki Fujiu, Noboru Shibata, Hiroshi Sukegawa
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Abstract
A method of writing data to a semiconductor memory device with memory cells, each of which stores data defined by threshold voltage thereof in a non-volatile manner, the device having first and second memory cells disposed adjacent to each other to be sequentially written in this order, the method including: performing a first data write operation for writing data defined by a threshold voltage lower than a desired threshold voltage into the first memory cell; performing a second data write operation for writing data into the second memory cell; and performing a third data writing operation for writing data defined by the desired threshold voltage into the first memory cell.
Claims20
A method of writing data to a semiconductor memory device with memory cells, each of which stores data defined by threshold voltage thereof in a non-volatile manner, the device having first and second memory cells disposed adjacent to each other to be sequentially written in this order, the method comprising:
- performing a first data write operation for writing data defined by a threshold voltage lower than a desired threshold voltage into the first memory cell;
- performing a second data write operation for writing data into the second memory cell;
- and
- performing a third data writing operation for writing data defined by the desired threshold voltage into the first memory cell.
A method of writing data to a semiconductor memory device, the device comprising word lines and bit lines which are arranged as crossing each other and electrically rewritable and non-volatile memory cells disposed at the respective crossings of the word lines and bit lines, the method comprising:
- performing a first data write operation for selectively writing a threshold voltage state lower than a desired threshold voltage into a first set of memory cells;
- performing, after the first data write operation, a second data write operation for selectively writing data into a second set of memory cells disposed adjacent to the first set of memory cells;
- and
- performing, after the second data write operation, a third data write operation for writing the desired threshold voltage state into the first set of memory cells with the same data pattern as in the first data write operation.
A method of writing data to a semiconductor memory device with memory cells, each of which stores data defined by threshold voltage thereof in a non-volatile manner, the device having first and second memory cells disposed adjacent to each other to be sequentially written in this order, the method being to write data with a desired threshold voltage into the first memory cell, wherein
- in case data to be written into the second memory cell is a first threshold voltage state, a first write-verify voltage equal to the desired threshold voltage is used at the data write time for the first memory cell;
- and
- in case data to be written into the second memory cell is a second threshold voltage state higher than the first threshold voltage, a second write-verify voltage lower than the desired threshold voltage is used at the data write time for the first memory cell.
A method of writing data to a semiconductor memory device, the device comprising word lines and bit lines which are arranged as crossing each other and electrically rewritable and non-volatile memory cells disposed at the respective crossings of the word lines and bit lines, the method comprising:
- applying a write voltage to at least two, first and second, memory cells arranged along a word line for writing data defined by a desired threshold voltage state;
- in case data to be written into a third memory cell disposed adjacent to the first memory cell has no influence on the first memory cell's threshold voltage, the third memory cell being selected by a second word line selected as following the first word line, performing write-verify with a first verify-voltage equal to the desired threshold voltage;
- and
- in case data to be written into a fourth memory cell disposed adjacent to the second memory cell has influence on the second memory cell's threshold voltage, the fourth memory cell being selected by the second word line, performing write-verify with a second verify-voltage lower than the desired threshold voltage.
Dependencies are inferred from the claim text.