Nand flash memory of using common p-well and method of operating the same

A method of programming a flash memory, comprising a plurality of strings, each string including a string selection transistor electrically connected to a bit line, memory cells electrically connected to the string selection transistor, and a ground selection transistor electrically connected to the memory cells, the method comprising:

• accumulating electrons in a source or drain region of the memory cell by applying a body voltage to a single p-well region formed under the plurality of strings;
• and
• trapping the accumulated electrons in a charge trap layer of the memory cell by applying a program voltage to a specific word line.

A method of erasing a flash memory, comprising a plurality of strings, each string including a string selection transistor electrically connected to a bit line, memory cells electrically connected to the string selection transistor, and a ground selection transistor electrically connected to the memory cells, the method comprising:

• accumulating holes in a source or drain region of the memory cell by applying a body voltage to a single p-well region formed under the plurality of strings;
• and
• trapping the accumulated holes in a charge trap layer of the memory cell by applying an erase voltage to all word lines.