Sub-7-nm textured ZrO2 with giant ferroelectricity

An similar to 6.5 nm pure ZrO2 thin film with a giant ferroelectric remanent polarization (P-r) of similar to 50 mu Ccm(-2) and an effective piezoelectric coefficient (d(33)) of 7-9 pm/V is reported. The film was prepared on a (111)oriented Pt electrode using plasma-enhanced atomic layer deposition at 300 degrees C, followed by annealing at 400 degrees C, and exhibited a preferred orientation of the orthorhombic (111) planes in the in-plane direction. The P-r value of similar to 50 mu Ccm(-2) is the largest reported to date for both perovskite and fluorite nanoscale ferroelectric thin films (< 120 nm) on a Pt electrode. Furthermore, the processing temperature of 300-400 degrees C is the lowest reported to date to produce a P-r of similar to 50 mu Ccm(-2) in nanoscale ferroelectrics on a Pt electrode. The giant P-r, ascribed to the preferred crystal orientation, was confirmed by the positive-up negative-down (PUND) polarization measurement with a long delay time to allow the relaxation of polarization. The effective d 33 was obtained using piezoresponse force microscopy with an interferometric displacement sensor to minimize the frequency-dependent artifacts and the effects of cantilever dynamics. The low-temperature preparation of the textured ZrO2 ultrathin film with a giant P-r is extremely advantageous for device scaling and process integration in advanced nanoelectronics. (C) 2020 Acta Materialia Inc. PublishedbyElsevierLtd. Allrightsreserved.

Automated summary

The study reports a similar to 6.5 nm pure ZrO2 thin film with a giant ferroelectric remanent polarization and effective piezoelectric coefficient on a Pt electrode, demonstrating excellent crystal orientation, which has potential implications for research and applications in nanoscale ferroelectric thin films.