SIMPLIFIED 0.35-MU-M FLASH EEPROM PROCESS USING HIGH-TEMPERATURE OXIDE (HTO) DEPOSITED BY LPCVD AS INTERPOLY DIELECTRICS AND PERIPHERAL TRANSISTORS GATE OXIDE

A simplified Flash EEPROM process was developed using high-temperature LPCVD oxide both as flash cells interpoly dielectrics and as peripher al transistors gate oxide (decoding logic). An O-2 anneal at 850 degre es C lowers charge trapping and interface traps density induced by Fow ler-Nordheim injection. However electron trapping remains slightly hig her than with dry thermal oxide. Similar memory charge loss and write- erase endurance are obtained as for ONO-insulated cells. HTO thus prov es to have the required quality and reliability to be used in Flash EE PROM.