Characterization and Low-Temperature Resistivity of Thin CeIn₃ Films Prepared by Co-sputtering

Abstract

Thin films of the heavy-fermion system CeIn₃ were prepared by simultaneous dc sputtering of two stoichiometric CeIn₃ targets and dc magnetron sputtering of a pure indium target in argon gas. The films were grown at a high rate of ∼30 Å/s on 10×20 mm² r-cut sapphire substrates heated to 500 °C. The resultant 120-nm thick films were continuous and stoichiometric, although indium precipitates of 1 μm size were observed on the surface. The films exhibited the expected cubic structure with the lattice parameter of 4.692 Å. They were predominantly (111) oriented, with minor amounts of (100) and (110) oriented grains. The dependence of the electrical resistivity on temperature, ρ(T), is typically that of bulk CeIn₃ with a clear maximum at around 50 K, followed by a linear decrease towards lower temperatures. At 10 K a kink in ρ(T) indicates the antiferromagnetic ordering of CeIn₃. The temperature dependence of the resistivity between 1.2 and 10 K is discussed in terms of electron-electron and electron-magnon scattering.