Top-Oxidation Effects On The Reliability Of Oxide-Nitride-Oxide Stacked Film

Effects of top-oxidation on the reliability of oxide/nitride/oxide (ONO) stacked films have been investigated for different oxidation methods. The leakage current electric field acceleration factor (beta) of mean time to failure, and reliability of ONO stacked films are strongly affected by the top-oxide thickness and the oxidation methods. The optimum top-oxide thickness on the nitride film is 2 to 3 nm. Leakage current and beta are improved by dry/TCA (1,1,1-trichloroethane) top-oxidation instead of dry oxidation. By using dry/TCA top-oxidation, high beta, low- leakage current low defect density, and highly reliable ONO stacked films can be obtained.