Electrical characterization of field-enhanced poly-Si nanowire SONOS memory

A novel omega-shaped-gated (Ω-Gate) poly-Si thin-film transistor (TFT) silicon-oxide-nitride-oxide-silicon (SONOS) nonvolatile memory devices fabricated by utilizing a simple process sequence are proposed for the first time. The Ω-Gate structure inherently covered two sharp corners constructed simply by a sidewall spacer formation. Due to the sharp corner geometry, the local electric fields across the tunneling oxide can be enhanced effectively, thus improving the memory performance. Based on this field enhanced scheme, the experimental results of Ω-Gate TFT SONOS reveals excellent program/erase (P/E) efficiency and larger memory window as compared to the conventional planar (CP) counterpart. Therefore, such an Ω-Gate TFT SONOS memory using simple and low-cost processes is very promising for the embedded flash on the system-on-panel applications.