Non-volatile semiconductor memory device and reading method thereof

Abstract

A non-volatile semiconductor memory device capable of eliminating influence of bit line (BL) leakage on reading and a reading method thereof. The non-volatile semiconductor memory device includes a memory array, a semiconductor well having a plurality of erase units, and a source switch array having a plurality of source switches. Each of the source switches is coupled to a common source line of one erase unit of the semiconductor well. Only one source switch among the source switches coupled to a selected erase unit among the erase units of the semiconductor well for reading is enabled during a reading operation. Thus, the BL leakage is prevented from affecting the reading operation on memory cells of the memory array, thereby improving the reliability of the non-volatile semiconductor memory device.