Semiconducting BaSi₂ film synthesis by close-spaced evaporation benefiting from mechanical activation of source powder by ball milling

Abstract

Close-spaced evaporation (CSE) is a film deposition process that enables epitaxial growth and is scalable to large areas. Mechanical activation of the source by ball milling can extend the growth window in CSE of BaSi₂ down to 700 °C. However, the close arrangement of the powder source (BaAl₄–Ni) and the substrate might contaminate the films. This study investigated the structural and electrical properties of the BaSi₂ films grown by CSE. It is found that the CSE BaSi₂ films are not significantly contaminated by powder particles and Ni. In addition, semiconducting properties with low carrier density and high mobility are revealed by Hall effect measurement.