Atomic Layer Deposition Plasma-Based Undoped-HfO2 Ferroelectric FETs for Non-Volatile Memory

A plasma-based undoped-HfO2 FeFET (ferroelectric FET) with non-volatile memory characteristics is demonstrated. Modifying the O-2 plasma period in plasma-enhanced atomic layer deposition (PE-ALD) is an effective approach to enhance the remnant polarization (P-r) up to 2P(r) = 25 mu C/cm(2) for the MFM (metal/ferroelectric/metal) structure with ferroelectric undoped-HfO2 thin films, and successful integration is implemented for the FeFET. The appropriate O-2 vacancies (V-o(2+)) benefit the formation of the ferroelectric phase since they play the role of dopants and help orthorhombic phase (o-phase) formation during post-metal annealing (PMA). The V-o(2+)-rich undoped-HfO2 FeFET exhibits a memory window (MW) of 0.5 V, 5 x 10(4) switching endurance cycles, and higher than 10(4) sec of data retention with V-P/E = +/- 5 V.

Automated summary

By modifying the O-2 plasma period in PE-ALD, the undoped-HfO2 FeFET demonstrates enhanced remnant polarization and successful integration.