The Effects of Program/Erase Cycles on the ONO Stack Layer in SONOS Flash Memory Cell Investigated by a Variable Amplitude Low Frequency Charge Pumping Technique
In this paper, influences of program/erase (P/E) cycles on the defect generation in a SONOS flash memory cell are studied by using a variable amplitude low frequency charge pumping technique. We observe that P/E cycles would generate new oxide and nitride traps, and degraded cell retention is observed. Besides, the increase of oxide and nitride trap densities follows a power law behavior as a function of P/E cycles. We also observe that these stress created oxide and nitride traps are unstable and will be eliminated rapidly during high temperature storage.
IEEE Transactions on Device and Materials Reliability