| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a flash memory device having uniform threshold voltage distribution without having non-programmed and over-programmed cells and its program verification method. <P>SOLUTION: The device is provided with a memory cell array block in which a plurality of flash memory cells are arranged, a program verification voltage generating section which generates program verification voltages in a variable manner, a wordline level selection section which transmits the program verification voltage and a page buffer which includes a latch that stores the data of the flash memory cells and resets the latch whenever the program verification voltage becomes low. During a prescribed number of program cycles, the program verification voltage is made same, program verification is performed, the voltage is made lower and a first latch of the page buffer is reset at a program unit loop in which the program verification voltage becomes low. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
