Electron-Beam Domain Writing in Stoichiometric LiTaO₃ Single Crystal by Utilizing Resist Layer

Ferroelectric crystals with patterned domain structures, such as LiTaO3, show excellent optical properties and have thus been used as materials for functional photonic devices. The effect of a resist layer on microscale domain engineering by electron-beam direct writing was examined using stoichiometric LiTaO3 single crystals. It was demonstrated that using an electron-beam (e-beam) resist to spatially confine the beam electrons, a regular, uniform dot array of domains (with a size of 1 µm) could be fabricated along the z-axis throughout the crystal. Ring-shaped domains could be fabricated by this technique. Our experiments pave the way for improving the e-beam domain fabrication method by utilizing a resist covering.