| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a flash memory element which is effective for preventing interference between adjacent cells by executing a program operation in a unit of word line and programming the cell sharing the same word lines, and to provide a programming method thereof. <P>SOLUTION: This programming method includes: a process for selecting all of bit lines connected to a plurality of memory strings respectively; a process for selecting the word line; a process for programming higher order bits after lower order bits are programmed to all of memory cells 100 connected to a selected word line; and a process for repeating the selection process of the word line and the program process of the upper order bits. Consequently, since the all of memory cells sharing the word lines are simultaneously programmed, the interference between the adjacent cells is effectively prevented. Further, since two cell strings share one page buffer (P1 to Pn, PB1 to PBi) for instance, expansion of the chip size is prevented, and area efficiency is improved. <P>COPYRIGHT: (C)2008,JPO&INPIT |
