METHOD FOR FORMING SINGLE DOMAIN OF LITHIUM NIOBATE SINGLE CRYSTAL

摘要

PURPOSE:To form single domains of lithium niobate single crystals perfectly by coating a specified thickness of paste consisting mainly of LiNbO3 single crystal powder on the surfaces of LiNbO3 single crystal, arranging noble metal electrode plates on these upper faces, heating them at or above the Curie temp., applying DC voltage to the electrodes, and gradually cooling them. CONSTITUTION:A paste consisting mainly of LiNbO3 single crystal powder is coated on the 2 opposite faces of LiNbO3 single crystal prepared by the single crystal pulling method to =3mm. thickness. Noble metal electrodes of Pt foil or the like are brought into close contact with these upper faces. They are heated to or above the Curie temp., i.e. 1,130 deg.C, maintained at this temp. for about 12hr, and then, they are gradually cooled at about 100 deg.C/hr, while DC voltage is applied to the electrodes, thus permitting to form completely separated single domain in allover a crystal with high yield.