PHYSICAL ORIGIN OF LONG-TERM CHARGE LOSS IN FLOATING-GATE EPROM WITH AN INTERPOLY OXIDE NITRIDE OXIDE STACKED DIELECTRIC

The long-term charge loss characteristic in a floating-gate EPROM cell with an oxide-nitride-oxide (ONO) interpoly stacked dielectric has been studied quantitatively. It is found that trapped electrons at the nitride-oxide interface can directly tunnel through a thin approximately 30-A top oxide. The estimated tunneling barrier height is about 2.6 eV, which is consistent with the previous result based on MNOS studies. The thermal activation of the long-term charge loss is believed caused by the availability of trapped electrons at the top oxide/nitride interface.