Improvement of erase-retention trade-off in metal–oxide–nitride–oxide–silicon memories by control of nitrogen profile in SiN charge-trapping layer

An improvement of the trade-off between erase speed and data retention characteristics in metal-oxide-nitride-oxide-silicon (MONOS) charge-trap-type flash memories is demonstrated by surface modification of the SiN charge-trapping layer. A SiN composition profile suitable for the nonuniform distribution of trapped electrons is realized by N-2 plasma treatment of highly Si-rich SiN, which leads to a sufficient erase speed while improving data retention characteristics. (C) 2014 The Japan Society of Applied Physics