Face-to-face annealed sputtered BaSi2

Abstract

Regarded as a promising candidate for absorber material in photovoltaic applications, BaSi2 confronts the challenge of high-quality material synthesis via low-cost processes. Here, we fabricated BaSi2 thin films through the industrially applicable sputtering technique with the face-to-face annealing (FTFA) approach. The employment of the FTFA approach leads to an improvement of the sputtered BaSi2 from perspectives of surface homogeneity and crystal quality. Various covers are applied in the FTFA, including BaSi2, glass, and Si, which causes alterations in the film's electrical and optical properties. These impacts of the FTFA method on sputtered BaSi2 films stem from two aspects, i.e., heat redistributions caused by the variation of thermal networks, and interfacial interactions within the confined space between the cover and the film. The FTFA approach provides a facile strategy for minimizing the impacts of BaSi2 surface oxidation during high-temperature processes. These results and findings can push forward the material development of BaSi2 and its photovoltaic applications.