Thermal annealing effects on the interaction between chromium and silicon carbide in a vacuum environment

Abstract

This study examines the morphological, structural, and chemical changes in Cr thin films deposited on SiC substrates and subjected to vacuum annealing at 700 °C, 800 °C, and 900 °C for 2 h. Cr thin films, approximately 250 nm thick, were deposited using the e-beam deposition technique. Post-annealing, additional phases, including chromium carbides and chromium oxides were identified, while Cr₃Si persisted as a stable phase across all temperatures. Morphological analysis showed that the as-deposited films were characterized by a uniform surface with finely distributed granules. Annealing at 700 °C increased grain size while retaining surface homogeneity. At 800 °C and 900 °C, the films exhibited significant grain growth and surface roughening, with the roughness increasing from 1.63 nm (as-deposited) to 13.8 nm at 900 °C. Additionally, localized segregation and nonhomogeneous surface features emerged at higher temperatures. XRD analysis revealed lattice expansion in the SiC substrate after annealing, indicating structural changes driven by thermal effects. The study highlights the influence of annealing on phase transformations, surface morphology, and structural integrity in Cr/SiC systems. These findings provide a deeper understanding of the thermal behavior of Cr/SiC composites, which is critical for optimizing their performance in high-temperature applications.