| 摘要 |
<p>PURPOSE:To improve reliability of reading operation by eliminating surely possibility in which a non-selection cell is selected in error, in a non-volatile semiconductor memory which can electrically perform batch erasing. CONSTITUTION:This semiconductor memory is provided with plural word lines WL1 WLm, plural bit lines BL11-BL1k,..., BLn1-BLnk, plural non-volatile memory cells Mhij, M111-M1mk,..., Mn11-Mnmk consisting of MIS transistors which are provided N 7 intersecting points of each word line WL1-WLm and each bit line BL11-BL1k,..., BLn1-BLnk and can externally and electrically control threshold voltage. Further, this device is provided with a source power supply supplying circuit 8 which applies reading bias voltage of a first potential to sources of the non-volatile memory cells at the time of reading, then constituted so that malfunction caused by an over erasing at the time of reading out is prevented.</p> |
