Bismuth-substituted iron garnet films prepared by RF diode sputtering

Single-phase, magnetically uniaxial Gd
3-x
Bi
x
Fe
5-y
Al
y
O
12
films have been prepared by RF diode sputtering with RF substrate bias on single-crystal (Gd,Ca,Mg)
3
(Ga,Zr)
5
O
12
and amorphous substrates. Epitaxial growth is observed by annealing of amorphous films for lattice misfits <0.03Å (tensile stress). Intrinsic properties, such as lattice constant, saturation magnetization, and polar magnetooptic effects, compare well with liquid-phase epitaxial films of equal composition. Film imperfections originating from particles expelled from the ceramic targets cause some optical loss, increased coercivity and increased linewidth in X-ray diffraction.