Effects of tunneling dielectrics formed by CO2 and N2O plasma-assisted oxidations on memory characteristics in p-channel LTPS NVM devices with ONO structure
Non-volatile memory (NVM) devices using carbon dioxide (CO2) and nitrous oxide (N2O) plasma-assisted tunneling layers have outstanding electrical properties measured at 300 K. However, the retention characteristics of NVM devices using CO2 and N2O plasma-assisted tunneling oxides are different at 360 K. The memory window of an NVM device using CO2 tunneling oxide was about 2.01 V (81.7%) after 10 years at 360 K. However, there was retention charge loss in the NVM device using a N2O tunneling layer at 360 K due to the temperature instability under negative bias. For an actual NVM device using N2O tunneling oxide, the memory window was reduced to about 1.58 V (65.6%) after 10 years at 360 K.