Thickness-dependence of oxide-nitride-oxide erase property in SONOS flash memory

With the device dimension scaling down, thickness-dependent property optimization for Oxide-Nitride-Oxide (ONO) used in SONOS flash memory is an important issue for the compatibility with scaled CMOS technology. With regard to the thickness-dependent property, trap-based erase behaviors should be investigated thoroughly because electron back-tunneling from gate make erase operation difficult. This paper focuses on the characteristics of ONO structures to find out the thickness-dependence of trap-based erase property at several nanoscales. Based on experimental details, one of important conclusion is that the blocking oxide and the charge trapping layer has further scaling possibility for achieving fast memory operation speed.