Novel Omega-Shaped-Gated TFT SONOS Memory

Abstract

A novel omega-shaped-gated (Omega-Gate) polycrystalline-silicon thin-film transistor (TFT) silicon-oxide-nitride-oxide-silicon (SONOS) nonvolatile memory with field-enhanced nanowire (FEN) structure has been proposed to improve the program and erase (P/E) performance. Each nanowire inherently had twin sharp corners fabricated simply by sidewall spacer formation to obtain high local electric fields. The field-enhanced carrier tunneling via such a structure led to faster P/E speed and wider memory window for the Omega-Gate SONOS as compared to the conventional planar (CP) counterpart. Such an Omega-Gate-TFT SONOS memory using a simple process is very suitable for future system-on-panel applications.