Fabrication of BaSi2 films on transparent CaF2 (111) substrates by molecular beam epitaxy for optical characterization

We have grown BaSi2 films on transparent CaF2(111) substrates by molecular beam epitaxy using Si template layers. The crystalline quality of the Si layers on the CaF2(111) was improved by electron stimulated desorption (ESD) technique prior to the deposition of Si. We successfully formed highly-oriented Si films on the ESD-treated CaF2(111) surface at 650 °C. The RHEED pattern suggested that the two kinds of 〈111〉-oriented Si epitaxial variants known as type A and type B were formed on the CaF2(111) substrates. The BaSi2 films were grown on the Si layers formed on CaF2(111) substrates, but they were not a-axis oriented, probably due to the rough surface of the Si layers.