Enhanced Ferroelectric Properties of Nitrogen‐Doped Bi 4 Ti 3 O 12 Thin Films

Ferroelectric nitrogen-doped Bi4Ti3O12 (BIT) and nitrogen-substituted BIT (N-BIT) thin films are prepared by an radiofrequency-magnetron-sputtering method such that nitrogen atoms are incorporated into oxygen sites. The remnant polarization Pr and the coercive field Ec of the nitrogen-doped BIT are enhanced relative to those of the undoped BIT (Figure). The leakage current of the nitrogen-doped BIT decreases and the fatigue properties improves compared to the undoped BIT.