Ferroelectric inversion layers formed by heat treatment of proton-exchanged LiTaO3

Abstract
We report that a ferroelectric inversion layer can be formed in LiTaO3 by proton exchange in benzoic acid melts followed by heat treatment at temperatures just below the Curie point. It is demonstrated that the inversion layer appears at the −c surface for LiTaO3, whereas it appears at the +c surface for LiNbO3. The dependence of the inversion layer thickness on the conditions of proton exchange and heat treatment is also reported.