Nonvolatile memory device performing two-way channel precharge

A program method of a nonvolatile memory device comprising a plurality of cell strings connected between a plurality of bit lines and a source line, each cell string comprising a first string selection transistor, a second string selection transistor, a plurality of memory cells, a second ground selection transistor, and a first ground selection transistor being arranged in series between a bit line and the source line, the program method comprising:

• initializing channels with respect to the plurality of cell strings;
• and
• performing a program operation on a selected memory cell among the plurality of memory cells,
• wherein the initializing of the channels comprises:
• applying a word line voltage having a power voltage applied to the nonvolatile memory device to one or more word lines of programmed memory cells among the plurality of memory cells;
• performing a first precharge on the channels of the plurality of cell strings using a first precharge voltage applied to the plurality of bit lines through the first and second string selection transistors;
• and
• performing a second precharge on the channels of the plurality of cell strings using a second precharge voltage applied to the source line through the first and second ground selection transistors,
• wherein the first precharge is performed simultaneously with the second precharge, and
• wherein the power voltage is greater than a ground voltage, and the first precharge voltage and the second precharge voltage are greater than the power voltage.

A nonvolatile memory device comprising:

• a memory cell array comprising a plurality of cell strings connected between a plurality of bit lines and a source line, each cell string comprising a first string selection transistor, a second string selection transistor, a plurality of memory cells, a second ground selection transistor, and a first ground selection transistor being arranged in series between a bit line and the source line;
• and
• a control circuit configured to perform an operation of initializing channels with respect to the plurality of cell strings and a program operation on a selected memory cell among the plurality of memory cells,
• wherein the control circuit is configured, in the operation of initializing the channels, to:
• perform a first precharge on the channels of the plurality of cell strings using a first precharge voltage applied to the plurality of bit lines through the first and second string selection transistors;
• and
• simultaneously perform a second precharge with the first precharge on the channels of the plurality of cell strings using a second precharge voltage applied to the source line through the first and second ground selection transistors,
• wherein the first precharge voltage and the second precharge voltage are greater than a power voltage applied to the nonvolatile memory device, and
• wherein the power voltage is greater than the ground voltage.