Lateral epitaxial growth of Ba_0.6Sr_0.4TiO₃ thin films

We report a novel growth technique for epitaxial thin films by combination of selective heteroepitaxial growth and lateral homoepitaxial growth. Ba _0.6Sr_0.4TiO₃ (BST) thin films were deposited on the substrates having patterned SiO_X layers at 450°C using pulsed laser deposition. Post annealing was carried out thereafter for lateral epitaxial growth. The difference in the crystallization temperature of BST thin film on the amorphous masking layers and lattice-matched single crystalline substrate enables selective nucleation and heteroepitaxial growth from the regions of single crystalline substrates during the film deposition. Lateral homoepitaxial growth is expected from the crystallized BST thin film toward the amorphous BST on SiO_x during the post annealing process. In this paper, a study on the difference in nucleation and growth behavior of BST thin films on the amorphous masking layers and lattice-matched single crystal substrates is presented.