Preparation of barium titanate with patterned microstructure by a novel electrophoretic deposition method

In order to prepare barium titanate (BaTiO3) with patterned microstructure, a novel electrophoretic method that uses a partially hydrolyzed highly concentrated solution of barium and titanium alkoxides was developed. By using electron beam lithography, a micro-patterned mold, that is a mold with an array of air holes of 250 nm arranged in a triangular lattice with a lattice constant of 500 nm was prepared on a Pt/Ti/SiO2/Si substrate. Electrophoretic deposition of BaTiO3 gel was carried out by negatively biasing the Pt/Ti/SiO2/Si substrate as cathode which had the resist mold on the surface. Removal of the resist mold left a gel material with a patterned structure that was transferred from the pattern of the mold. The gel material was confirmed by ICP-AES to have nearly the stoichiometric composition of BaTiO3, that is, a composition in which Ba:Ti = 1: 1 in molar ratio.