A BE-SONOS (Bandgap Engineered SONOS) NAND for Post-Floating Gate Era Flash Memory

BE-SONOS [1] is successfully integrated in a 0.13 mum NAND Flash technology. BE-SONOS device employs a bandgap engineered ONO barrier, which allows efficient hole tunneling erase and yet prevents the direct tunneling leakage during retention. BE-SONOS can overcome the fundamental limitation of the conventional SONOS, for which good data retention and fast erase speed cannot be simultaneously achieved. BE-SONOS NAND Flash has comparable performance with the floating-gate NAND Flash, but also the scaling capability below 40 nm technology. BE-SONOS NAND array functions such as the program-inhibit method (using self-boosting technique) and reading characteristics are demonstrated in this work.