Non-volatile memory device optimized for a surface mount technology (SMT) process and an operating method thereof
An operating method of a non-volatile memory device, the method including: receiving a program command from an external device; determining an operating mode in response to the program command; when the operating mode is a surface mount technology (SMT) mode, performing an initial program operation in which a plurality of memory cells are programmed through a plurality of steps to form a first threshold voltage distribution; and when the operating mode is a normal mode, performing a normal program operation in which the plurality of memory cells are programmed through a single step to form a second threshold voltage distribution, wherein the first threshold voltage distribution is narrower in width than the second threshold voltage distribution.
1. An operating method of a non-volatile memory device, the method comprising:
receiving a program command from an external device;
determining an operating mode in response to the program command;
when the operating mode is a surface mount technology (SMT) mode, performing an initial program operation in which a plurality of memory cells are programmed through a plurality of steps to form a first threshold voltage distribution; and
when the operating mode is a normal mode, performing a normal program operation in which the plurality of memory cells are programmed through a single step to form a second threshold voltage distribution,
wherein the first threshold voltage distribution is narrower in width than the second threshold voltage distribution,
wherein the performing of the initial program operation includes:
performing a 1-step initial program operation in which memory cells selected from the plurality of memory cells are programmed based on first initial program voltages and first initial verify voltages; and
performing a 2-step initial program operation in which the selected memory cells are programmed based on second initial program voltages and second initial verify voltages to form the first threshold voltage distribution,
wherein the performing of the initial program operation further includes:
determining whether a word line of an erase state is present in a selected memory block;
when the word line of the erase state is present in the selected memory block, programming dummy data in memory cells associated with the word line of the erase state; and
when the word line of the erase state is absent from the selected memory block, completing the initial program operation.
2. The method of claim 1 , wherein the plurality of memory cells targeted for the initial program operation and the normal program operation store the same number of bits.
3. The method of claim 1 , wherein the 1-step initial program operation and the 2-step initial program operation are performed in an incremental step programming (ISPP) technique.
4. The method of claim 3 , wherein an increment of the first initial program voltages applied to a selected word line in the 1-step initial program operation is greater than an increment of the second initial program voltages applied to the selected word line in the 2-step initial program operation.
5. The method of claim 3 , wherein a magnitude of each of the second initial verify voltages is greater than a magnitude of its corresponding one of the first initial verify voltages.
6. An operating method of a non-volatile memory device, the method comprising:
receiving a read command from an external device;
determining an operating mode in response to the read command;
when the operating mode is a surface mount technology (SMT) mode, performing a first read operation based on a first read level set; and
when the operating mode is a normal mode, performing a second read operation based on a second read level set,
wherein the first read level set is used to read a first threshold voltage distribution of memory cells programmed in the SMT mode,
wherein the second read level set is used to read a second threshold voltage distribution of memory cells programmed in the normal mode,
wherein the first threshold voltage distribution is narrower in width to mitigate high-temperature effects during the SMT process compared to the second threshold voltage distribution.
7. The method of claim 6 , wherein the first read level set includes first read voltages,
wherein the second read level set includes second read voltages, and
wherein a magnitude of each of the first read voltages is different from a magnitude of its correspond one of the second read voltages.
8. The method of claim 7 , wherein the magnitude of each of the second read voltages is larger than the magnitude of its corresponding one of the first read voltages.
9. The method of claim 6 , wherein the first read level set includes first read times,
wherein the second read level set includes second read times, and
wherein each of the first read times is different from its corresponding one of the second read times.
10. The method of claim 9 , wherein each of the first read times is greater than its corresponding one of the second read times.
11. An operating method of a non-volatile memory device, the method comprising:
performing an initial program operation in which a plurality of memory cells are programmed based on a program command through a plurality steps to form a first threshold voltage distribution, in a surface mount technology (SMT) mode;
performing a first read operation in which data programmed in the plurality of memory cells after a surface mount technology is applied are read based on a first read level set, in the SMT mode;
performing a normal program operation in which the plurality of memory cells on which the first read operation is completely performed are programmed based on the program command to form a second threshold voltage distribution, in a normal mode; and
performing a second read operation in which data programmed in the plurality of memory cells are read based on a second read level set different from the first read level set, in the normal mode,
wherein the first threshold voltage distribution is narrower in width than the second threshold voltage distribution,
wherein the performing of the initial program operation further includes:
determining whether a word line of an erase state is present in a selected memory block;
when the word line of the erase state is present in the selected memory block, programming dummy data in memory cells associated with the word line of the erase state; and
when the word line of the erase state is absent from the selected memory block, completing the initial program operation.
12. The method of claim 11 , wherein the plurality of memory cells targeted for the initial program operation and the normal program operation store the same number of bits.
13. The method of claim 11 , wherein the performing of the initial program operation further includes:
performing a 1-step initial program operation in which memory cells selected from the plurality of memory cells are programmed based on first initial program voltages and first initial verify voltages; and
performing a 2-step initial program operation in which the selected memory cells are programmed based on second initial program voltages and second initial verify voltages to form the first threshold voltage distribution.
14. The method of claim 13 , wherein the 1-step initial program operation and the 2-step initial program operation are performed in an incremental step programming (ISPP) manner.
15. The method of claim 14 , wherein an increment of the first initial program voltages applied to a selected word line in the 1-step initial program operation is greater than an increment of the second initial program voltages applied to the selected word line in the 2-step initial program operation.
16. The method of claim 14 , wherein a magnitude of each of the second initial verify voltages is greater than a magnitude of its corresponding one of the first initial verify voltages.
17. The method of claim 11 , wherein the first read level set includes first read voltages,
wherein the second read level set includes second read voltages, and
wherein a magnitude of each of the second read voltages is larger than a magnitude of its corresponding one of the first read voltages.
18. The method of claim 11 , wherein the first read operation and the second read operation are performed based on a flag,
the method further comprising:
when a read command is received, determining the flag;
when the flag is a predetermined value, performing the first read operation based on the first read level set, and
when the flag is not the predetermined value, performing the second read operation based on the second read level set.