Studies on the growth of epitaxial bismuth-substituted iron garnet on gadolinium gallium garnet single crystals by pulsed laser deposition

In this paper, we present extensive investigations of the growth of bismuth-substituted iron garnet Bi3Fe5O12 (BIG) on (0 0 1)-, (1 1 1)- and (1 1 0)-oriented gadolinium gallium garnet Gd3Ga5O12 (GGG) and doped GGG (SGGG, S*GGG) substrates by pulsed laser deposition. The growth has been studied by the use of in-situ reflecting high-energy electron diffraction, atomic force microscopy, scanning electron microscopy and X-ray diffraction. We found 3D island growth to be the dominant growth mode for the BIG films. Additionally, we present a special technique to create very large BIG growth islands. This method involves the use of a metallic bismuth iron ablation target and partially shielding the substrate during deposition. The growth islands have a characteristic geometry depending on the cut of the substrate. We could explain their shapes by the assumption that growing BIG tends to form {1 1 0} facets.