| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a multi level flash memory device and a program method. <P>SOLUTION: This device is the flash memory device provided with a plurality of memory cells in which each cell stores an amount of charges indicating two possible states or more and a control circuit coupled to the memory cells. In the control circuit, programming voltage and verification voltage are applied alternately to the memory cells until all memory cells reach a desired state. Also, the method is provided with a step in which at least one programming pulse is applied to the memory cell, a step in which it is verified whether each memory cell reaches the desired state or not, a step in which the memory cell programmed at the highest state is selected. and a step in which at least one additional programming pulse is applied to the selected memory cell without further verifying a state of the selected memory cell. The program method characterized by providing above steps. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
