| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a nonvolatile memory device which classifies an upper side memory register and a lower side memory register by locating a page buffer to a center part of a plane. <P>SOLUTION: A multilevel cell program method for a volatile memory device comprises: a step in which a page buffer including a first register connected with a first memory cell group and a second register connected with a second memory cell group is provided, and a low-order bit program is completed for each memory cell; a step in which a high-order bit data is set to a first node of a data latch part of the first register; a step in which a high-order bit program is performed; a step in which first data is set to the first node when programmed at a first verification voltage or higher; a step in which second data of a level reverse to that of the first data is set to the first node when programmed at a second verification voltage or higher; a step in which the first data is set to the first node when programmed at a third verification voltage or higher; and a step in which the high-order bit program is repeated by the data set to the first node. <P>COPYRIGHT: (C)2013,JPO&INPIT |
