Study on SONOS nonvolatile memory technology using high-density plasma CVD silicon nitride

Abstract

With the replacement of silicon nitride in an oxide/nitride/oxide (ONO) gate-stacked structure, trap-rich high-density plasma chemical vapor deposited (HDPCVD) SiNx shows a more significant threshold-voltage shift (memory window) than that of conventional low pressure (LP)CVD Si3N4. Also, low-temperature (2000degreesC) deposited HDPCVD silicon nitride shows a good retention characteristic, the same as high-temperature (780degreesC) LPCVD Si3N4. With the optimization of thickness in the gate-stacked ONO structure, low-voltage and reliable operation, lower than 5 V, is realizable. (C) 2004 The Electrochemical Society.