Memory device and method of operating memory device
The present technology includes a memory device and a method of operating the memory device. The memory device includes a memory block including a plurality of memory cells connected to word lines, peripheral circuits configured to generate operation voltages to be applied to the word lines, and control logic configured to control the peripheral circuits in response to a program command, a read command, or an erase command. The peripheral circuits include a voltage generator that adjusts a section of threshold voltage distributions of memory cells to be programmed among the memory cells, according to a distance between the word lines.
1. A memory device comprising:
a memory block including a plurality of memory cells connected to word lines;
peripheral circuits configured to generate operation voltages to be applied to the word lines; and
control logic configured to control the peripheral circuits in response to a program command, a read command, or an erase command,
wherein the peripheral circuits include a voltage generator that is configured such that, when the word lines are separated by a first distance, a voltage difference between an erased state and a programmed state is a first voltage, and when the word lines are separated by a second distance that is smaller than the first distance, the voltage difference between the erased state and the programmed state is a second voltage that is smaller than the first voltage.
2. The memory device of claim 1 , wherein the memory block comprises:
a vertical channel film extending in a first direction perpendicular to a substrate; and
the word lines are stacked and spaced apart from each other in the first direction along the vertical channel film.
3. The memory device of claim 2 , wherein the distance between the word lines is a distance between word lines adjacent to each other in the first direction.
4. The memory device of claim 1 , wherein the voltage generator generates program verify voltages having a higher level as the distance between the word lines is increased and generates program verify voltages having a lower level as the distance between the word lines is decreased.
5. The memory device of claim 1 , wherein the voltage generator generates an erase verify voltage at a constant level regardless of the distance between the word lines.
6. The memory device of claim 1 , wherein the voltage generator generates a program voltage and a pass voltage corresponding to the program command, a read voltage corresponding to the read command, and an erase voltage corresponding to the erase command.
7. The memory device of claim 6 , wherein the voltage generator includes a verify voltage generator that generates program verify voltages corresponding to the program command.
8. A memory device comprising:
a memory block including a vertical channel film extending in a vertical direction on a substrate, and word lines stacked and spaced apart from each other along the vertical channel film; and
a voltage generator configured to generate program voltages, pass voltages, and program verify voltages to be applied to the word lines, during a program operation,
wherein the voltage generator is additionally configured such that, when the word lines are separated by a first distance, a voltage difference between an erased state and a programmed state is a first voltage, and when the word lines are separated by a second distance that is smaller than the first distance, the voltage difference between the erased state and the programmed state is a second voltage that is smaller than the first voltage.
9. The memory device of claim 8 , wherein a program window including threshold voltage distributions of memory cells is set according to the distance between the word lines, and
the voltage generator adjusts the level of the program verify voltages according to the set program window.
10. The memory device of claim 9 , wherein the voltage generator increases a start voltage and an end voltage of the program window as the distance between the word lines is increased and reduces the start voltage and the end voltage of the program window as the distance between the word lines is decreased.
11. The memory device of claim 8 , wherein the voltage generator generates an erase verify voltage at a constant level regardless of the distance between the word lines.
12. A method of operating a memory device, the method comprising:
setting a program window including threshold voltage distributions of a program according to a distance between word lines such that, when the word lines are separated by a first distance, a voltage difference between an erased state and a programmed state is a first voltage, and when the word lines are separated by a second distance that is smaller than the first distance, the voltage difference between the erased state and the programmed state is a second voltage that is smaller than the first voltage.
13. The method of claim 12 , wherein a start voltage and an end voltage of the program window are set according to the verify voltage.
14. The method of claim 13 , wherein the start voltage and the end voltage of the program window are set to higher voltage levels when the distance between the word lines is wider and are set to lower voltages levels when the distance between the word lines is narrower.