Modified Potential Well Formed by \hbox/ \hbox/\hbox/\hbox for Flash Memory Application

This paper proposes a modified engineered-potentialwell (MW) for NAND flash memory application. The MW was formed by using a transitional SiO 2 /SiO x ,Na-TiO x ,N y tunnel barrier, a trap-rich TiO 2 trapping layer, and an abrupt SiO 2 block barrier. The transitional tunnel barrier shrinks to enhance the tunneling of carriers during programming/erasing (P/E) and extends to suppress charge loss during data retention. Deep-level transient spectroscopy suggests that this tunnel barrier has few shallow traps after a N 2 + O 2 thermal treatment, and the TiO 2 trapping layer has deep electron traps. With the variable tunnel barrier and deep electron traps, the MW device showed promising performance in fast programming ( 10 6 P/E cycles), large threshold voltage window (ΔV th =M> V), as well as improved data retention at 125 °C.