The relationship among crystallographic orientation and quality, flatness of a surface, electrical properties and thickness for lead titanate (PbTiO3: PTO) ultra-thin films is reported. A crystallographic orientation changed from (100) to (001) with an increase in film thickness. However, a (001) plane orientation ratio α saturated to 0.85 and root square mean (RMS) of flatness saturated to 1.4nm when the film thickness was approximately 90nm. A PTO film thinner than approximately 90nm had a larger dielectric constant and that thicker than approximate 90nm showed ferroelectric property.
ASJC Scopus subject areas