New characterization methodology for flash memory cell using CAST structure

Hole trapping occurred during program/erase (P/E) operation in a flash EEPROM. To the authors' knowledge, there is still no effective method for characterization of the endurance performance of flash EEPROMs at the key test level. In this paper, we propose a simple and fast method to evaluate the endurance performance of a 12 kbit flash EEPROM cell array stress test (CAST) structure. Based on this method, we can easily detect subtle defects as well as the effectiveness of the hole detrapping method used to suppress the tail-bits.