Understanding of deposition mechanism of vanadium on LiF with large mismatch by facing target sputtering (FTS).

[Display omitted] • Over 1.5 μm thick nearly crack-free vanadium films were grown on LiF via facing target sputtering (FTS). • The behaviors of plasma discharge in FTS and microscopic morphology of V films were simulated. • The growth model of vanadium films was established based on experimental and numerical simulation results. • The grain boundary relaxation model contributes to reveal the role of micro-sized gaps to stresses release. V/LiF is a significant window material for investigation of phase transition of materials at ultra-high pressure which is a fundamental issue in condensed matter physics. However, the large mismatch of lattice and thermal makes vanadium growth on LiF as big challenge. In this current study, over 1.5 μm thick vanadium films were grown on LiF via facing target sputtering (FTS). The transmission electron microscopy (TEM) observation showed the grown vanadium films feature vertically well-aligned columnar crystals with numerous micro-sized gaps. For understanding the deposition mechanism, the behaviors of plasma discharge, transport of sputtered atoms and growth of films were simulated by particle-in-cell Monte Carlo collision (PIC-MCC) and Kinetic Monte Carlo (KMC) methods, respectively. The growth model of vanadium film was established based on the experimental and simulation results. And the micro-sized gaps of columnar crystals contribute to release residual stresses generated by large mismatch, which can be explained by the grain boundary relaxation model. [ABSTRACT FROM AUTHOR]