Cycling induced performance degradation of flash EEPROMs has been reported for VB=0 and VB<0 programming operation. Compared to VB=0, VB<0 programming shows lower interface degradation for identical cumulative charge fluence (for program) during repetitive program/erase cycling. Reduction in programming gate current has been found to be lower for VB<0 operation under identical interface damage as the VB=0 case. As a consequence, programming under VB<0 condition has been found to cause lower degradation of programming time and programmed VT due to cycling.
S. Mahapatra, S. Shukuri, Jeff Bude