Inverted domain structure in ferroelectric crystals with polarization in the crystal plane

摘要

Ferroelectric domain regions are formed in a ferroelectric crystal cut so that the polarization direction is in the plane of the crystal and is along the z direction is disclosed. A periodic ion exchange grating on the surface of the crystal with grating is provided on the surface of the crystal with grating lines parallel to the Z-axis of the crystal by a combination of photolithography and ion-exchange techniques and then applying a uniform field across two electrode pads on the crystal surface, thus creating an electric field opposite to the polarization direction (+ Z direction) of the crystal. The electric field reverses the domains in selective regions defined by the ion exchange grating formed in the earlier step. This gives rise to a periodically reversed domain grating on the crystal surface.