 In 1991, NEC researchers including N. Kodama, K. Oyama and Hiroki Shirai described a type of flash memory with a charge trap method.In 1998, Boaz Eitan of Saifun Semiconductors (later acquired by Spansion) patented a flash memory technology named NROM that took advantage of a charge trapping layer to replace the floating gate used in conventional flash memory designs.In 2000, an Advanced Micro Devices (AMD) research team led by Richard M. Fastow, Egyptian engineer Khaled Z. Ahmed and Jordanian engineer Sameer Haddad (who later joined Spansion) demonstrated a charge-trapping mechanism for NOR flash memory cells.