Method for forming split-gate flash cell for salicide and self-align contact

(1) Field of the Invention A method is disclosed for forming a split-gate flash memory cell having a salicidated control gate and self-aligned contacts. Salicidation is normally performed with single gate devices, such as logic devices. In a split-gate where the control gate overlays the floating gate with an intervening intergate oxide layer, it is conventionally incompatible to form self-aligned silicides over the control gate due to its position at a different level from that of the floating gate. Furthermore, oxide spacers that are normally used are inadequate when applied to memory cells. It is shown in the present invention that by a judicious use of an additional nitride/oxide layer over the control gate, oxide spacers can now be used effectively to delineate areas on the control gate that can be silicided and also self-aligned. Hence, with this method, salicidation and self-aligned contact techniques can be used not only on the same VLSI and ULSI chips having both peripheral logic devices and memory devices, but also in memory devices themselves.