| Ferroelectric materials have been widely used because of their unique properties. The ferroelectric polarization can be switched in a different direction to store the logic information for the memories,and the materials have the excellent piezoelectric and pyroelectric properties which are useful for the application of the sensor devices.The film deposition technique had been developed in past years to optimize the film quality for some specifically applications,such as ferroelectric random access memories which requires the fast accessing speed of the stored information,the good scaleablility of the cell size,and the improved reliability of the performance.Antiferroelectric thin films are perfect for the high density charge storage device because of their back switchable domains and the large dielectric permittivity. However,those chemical compositions of antiferroelectric thin films are restricted because of the phase transition from antiferroelectric to ferroelectric.Through hydrogen ion implantation to make ferroelectric thin films into antiferroelectric behavior can solve the problem above.This thesis details our researches of the new antiferroelectric behavior found in ferroelectric thin films through hydrogen implantation technique.It is found that article antiferroelectric thin films could be made through ion implantation for any present ferroelectric thin films regardless of their components,which offers an alterntive way to make antiferroelectric devices by using ferroelectric thin films,and new physics involved is extracted from experimental data for the fundamental understanding of the domain switching behavior in ferroelectric thin films.Our results predicted the built-in internal field within the implanted ferroelectric thin films that backswitches all the domains after the removal of the external field,in demonstration of an antiferroelectric behavior.The phenomenon within our work is new and fully explained in this thesis.
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