2-bit Recessed Channel SONOS Memory with Vertical Split Gate Structure

A 2-bit recessed channel SONOS memory with vertical split gate structure is characterized through 2-dimensional numerical simulation. With a long effective channel length, this device is immune to the short channel effect [1]. The charge storage nodes are self-lifted from the bottom-side of channel and hence the second-bit effect is effectively suppressed. Furthermore, increased charge injection efficiency is expected because of the split gate structure. Therefore, enhanced programming characteristics with low second-bit effect can be achieved with simpler fabrication processes compared with the fanner methods [2], [3].