| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To raise the reliability of programming and erasing of nonvolatile memory elements. <P>SOLUTION: A method which programs a memory array having a plurality of memory cells includes: making a computer execute a verification step 1 for verifying the programmed state or the unprogrammed state of a pertinent memory cell for every memory cell to be programmed, a flag adding step 2 for adding a flag to the memory cell which is verified that it is an unprogrammed cell at the time of any verification step in a plurality of verification steps after it is verified that it is already programmed before, a first impression step 3 for impressing a programming pulse having a programming level to the unprogrammed cell being a memory cell to which a flag is not added, a repeat step 4 for repeating the verification step 1, the flag adding step 2 and the first impression step 3 until all the memory cells are verified to be programmed at least once and a second impression step 5 for impressing a boost pulse having a boost programming level lower than the programming level to the cell to which the flag is added. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
