| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor memory device which performs normal read-out even if an excess-written memory cell exists in a NAND type MONOS memory, and also to provide its manufacturing method. <P>SOLUTION: MONOS memory cells TR1-TR4 are provided in series between a bit line BL and a ground potential GND of a silicon substrate. Word lines WL1-4 corresponding to each memory cell are provided. MOSFET TR1F-TR4F are connected respectively in parallel to the MONOS memory cells TR1-TR4. These MOSFET is a normal enhancement type element which is turned on sufficiently by power source voltage Vcc for a gate. A threshold value of these MODFET is set at a value being higher than reference voltage 0V and being a threshold value of a write-in state or less. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
