Soft programming method of non-volatile memory device
A non-volatile memory device includes a first cell group including memory cells other than memory cells adjacent to a drain select transistor in a block, and a second cell group including the memory cells adjacent to the drain select transistor in the block. An erase operation is performed on the memory cells in the block. The first cell group is programmed by applying a first soft programming voltage to the first cell group. The second cell group is programmed by applying a second soft programming voltage to the second cell group.
1. A soft programming method of a non-volatile memory device, the method comprising:
providing a first cell group including memory cells other than memory cells adjacent to a drain select transistor in a block, and a second cell group including the memory cells adjacent to the drain select transistor in the block;
performing an erase operation on the memory cells in the block;
programming the first cell group by applying a first soft programming voltage to the first cell group; and
programming the second cell group by applying a second soft programming voltage to the second cell group.
2. The soft programming method of claim 1 , wherein during programming of the first cell group, cells adjacent to a source select transistor are first programmed sequentially.
3. The soft programming method of claim 1 , wherein the second soft programming voltage is lower than the first soft programming voltage.
4. The soft programming method of claim 1 , wherein the first soft programming voltage is approximately 1V higher than the second soft programming voltage.
5. The soft programming method of claim 1 , wherein the first soft programming voltage ranges from approximately 12 to 14V.
6. A soft programming method of a non-volatile memory device, the method comprising:
providing a first cell group including memory cells other than memory cells adjacent to a source select transistor in a block, and a second cell group including the memory cells adjacent to the source select transistor in the block;
performing an erase operation on the memory cells in the block;
programming the first cell group by applying a first soft programming voltage to the first cell group; and
programming the second cell group by applying a second soft programming voltage to the second cell group.
7. The soft programming method of claim 6 , wherein during programming of the first cell group, cells adjacent to a drain select transistor are first programmed sequentially.
8. The soft programming method of claim 6 , wherein the second soft programming voltage is lower than the first soft programming voltage.
9. The soft programming method of claim 6 , wherein the first soft programming voltage is approximately 1V higher than the second soft programming voltage.
10. The soft programming method of claim 6 , wherein the first soft programming voltage ranges from approximately 12 to 14V.
11. A soft programming method of a non-volatile memory device, the method comprising:
providing a first cell group including memory cells adjacent to a drain select transistor in a block, a second cell group including memory cells adjacent to a source select transistor in the block, and a third cell group including memory cells other than the memory cells included in the first cell group and the second cell group in the block;
performing an erase operation on the memory cells in the block;
applying a first soft programming voltage to the first cell group;
applying a second soft programming voltage to the second cell group; and
applying a third soft programming voltage to the third cell group, wherein the third soft programming voltage is higher than the first and second soft programming voltages.
12. A soft programming method of a non-volatile memory device, the method comprising:
providing a first cell group including memory cells adjacent to a select transistor in a block, and a second cell group including memory cells other than the cells adjacent to the select transistor in the block;
performing an erase operation on the memory cells in the block; and
performing programming so that a threshold voltage of the first cell group is higher than a threshold voltage of the second cell group.