New write/erase operation technology for flash EEPROM cells to improve the read disturb characteristics

Abstract

This paper describes the new write/erase operation methods in order to improve the read disturb characteristics for flash EEPROM cells which are written by channel hot electron injection and erased by F-N tunneling emission from the floating gate to the substrate. The new operation method is either applying a reverse polarity pulse after each erase pulse or applying a series of shorter erase pulses instead of a long single erase pulse. It is confirmed that by using the above operation method, the leakage current can be suppressed, and then the read disturb life time after 10/sup 5/ cycles W/E operation is more than 10 times longer in comparison with the conventional method.<>