A Study on Tunneling Current of ONO Films and Data Retention Effects in Flash Memories

In this research, 5 different thicknesses of oxide-nitride-oxide (ONO) inter-poly-gate dielectrics in flash memories are studied. Besides the experiments of analyzing program/erase speeds, various I-V tests have also being conducted to understand the tunneling characteristics of these ONO films. Data retention effects are also investigated by measuring the threshold voltage shifts consecutively up to 200 h of 250℃ baking. All the findings are analyzed and concluded to propose a set of ONO film scaling rules.