Effects of Floating Gate Profile on Cell Characteristics of 4XNM FG-First ETOX Nor Flash Memory

The FG-first technique is proposed in order to evade the typical process challenges as the NOR-flash memory scaling down to below 4Xnm generation. In this letter, the effect of floating gate top profile on the flash cell characteristics are investigated, the characteristics of arch-FG structure and planar-FG structure are trialed by the simulation and experiment. The planar-FG structure features better floating gate profile uniformity, larger cell memory window, tighter threshold voltage distribution width and higher chip prober yield, which can greatly enhance the process window and device window for the 4Xnm NOR-flash memory.