Epitaxial Growth of α-Fe₂O₃ and Cr₂O₃ Sputtered Films on Garnet

Abstract
Thin films of α-Fe₂O₃ and Cr₂O₃ have been prepared in situ on gadolinium gallium garnet (GGG) (111) substrates by rf sputtering. The α-Fe₂O₃ film showed a strong [0006] texture normal to the film plane at 500°C when deposited on an initial layer with 7 - 10 nm thick grown at ambient temperature, while the Cr₂O₃ films with a [0006] texture grew in pure Ar without the initial layer. X-ray pole figure analysis showed that nearly single crystalline (0001) films of α-Fe₂O₃ and Cr₂O₃ were grown on GGG (111) with an in-plane alignment of [2-1-10] parallel to GGG [1-10]. Thus, these films with the corundum crystal structure may be a promising buffer layer for achieving heteroepitaxy of various ferrite thin films onto a common substrate of GGG.