Incomplete Dipoles Flipping Produced Near Hysteresis-Free Negative Capacitance Transistors

In this letter, we experimentally investigate the impact of polarization (P) switching behaviors on hysteretic and near hysteresis-free (NHF) negative capacitance field-effect transistors (NCFETs). Compared with the typical abrupt P switching in hysteretic devices, NHF NCFETs show gradual and continuous response of P under applied voltage, indicating that the mechanism underlying NHF characteristics is incomplete dipoles flipping, rather than complete dipoles switching. It has also been confirmed by a small amount of P charge (0.1 similar to 0.2 mu C/cm(2)), which is still capable of achieving electrical performance improvement. This favors the device operation voltage scaling and reliability improvement for logic transistor applications.