Semiconductor device
A semiconductor device includes a memory block including memory cells coupled between bit lines and a common source line and operated by voltages applied to word lines, and an operation control block suitable for performing an erase operation and a pre-program operation on the memory block, wherein the operation control block performs an erase level control operation after the erase operation is completed so that threshold voltages of the memory cells relatively close to the bit lines and threshold voltages of the memory cells relatively close to the common source line are distributed at different erase levels.
1. A semiconductor device, comprising:
a memory block including memory cells coupled between bit lines and a common source line and operated by voltages applied to word lines; and
an operation control block suitable for performing an erase operation on the memory block,
wherein the operation control block performs an erase level control operation including a pre-program operation by applying voltages, different from the voltages applied to the word lines close to the common source line, to the word lines close to the bit lines, after the erase operation is completed, to distribute threshold voltages of the memory cells relatively close to the bit lines to be different from threshold voltages of the memory cells relatively close to the common source line.
2. The semiconductor device of claim 1 , wherein the word lines are grouped into a first word line group relatively close to the common source line and a second word line group relatively close to the bit lines.
3. The semiconductor device of claim 2 , wherein the operation control block performs the erase level control operation so that a second erase level of the memory cells included in the second word line group is lower than a first erase level of the memory cells of the first word line group.
4. The semiconductor device of claim 2 , wherein when the erase level control operation is performed on the first word line group, the operation control block applies a first voltage to the word lines of the first word line group and a second voltage lower than the first voltage to the word lines of the second word line group.
5. The semiconductor device of claim 4 , wherein when the erase level control operation is performed on the second word line group, the operation control block applies a third voltage to the word lines of the second word line group and a fourth voltage lower than the third voltage to the word lines of the first word line group.
6. The semiconductor device of claim 5 , wherein the second voltage is equal to the third voltage.
7. The semiconductor device of claim 2 , wherein the erase level control operation is performed on the first word line group by the pre-program operation of the operation control block.
8. The semiconductor device of claim 7 , wherein when the pre-program operation is performed on the first word line group, a program voltage is applied to a selected word line of the first word line group, and a pass voltage is applied to the second word line group.
9. The semiconductor device of claim 2 , wherein the operation control block applies a pre-program voltage to first memory cells included in the first word line group to control an erase level of the first memory cells, and the operation control block applies a pass voltage to second memory cells included in the second word line group to control an erase level of the second memory cells.
10. The semiconductor device of claim 1 , wherein the word lines are grouped into three or more word line groups.
11. The semiconductor device of claim 10 , wherein more word lines are included in a word line group relatively close to the bit lines than those included in the a word line group relatively close to the common source line.
12. The semiconductor device of claim 10 , wherein the number of erase levels of the memory cells corresponds to the number of word line groups.
13. The semiconductor device of claim 10 , wherein the operation control block performs pre-program operations under different conditions to control erase levels of the memory cells included in the word line groups.
14. The semiconductor device of claim 13 , wherein the operation control block changes a pre-program voltage depending on a position of each word line group between the bit lines and the common source line.
15. The semiconductor device of claim 14 , wherein a first pre-program voltage is applied to the memory cells of the word line group relatively close to the common source line, and a second pre-program voltage, which is lower than the first pre-program voltage, is applied to the memory cells of the word line group relatively close to the bit lines.