Structure and properties of protective amorphous ZrBN coating

This article presents a comprehensive study of the ZrBN coating characterized by high transmittance. The coating was deposited by magnetron sputtering of a ZrB2 target in nitrogen atmosphere. The coating structure was studied by scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and glow-discharge optical emission spectroscopy. The mechanical properties were assessed by nanoindentation. The transmittance and reflectivity, as well as the refractive index, were measured by spectrophotometry. Special attention was paid to in situ transmission electron microscopy studies of thermal stability of the coatings at different heating temperatures and exposure times. Due to the high volume fraction of the BN phase and low defect density, the coating was characterized by transmittance of 70–90 % in the wavelength range of 600–2500 nm. The films exhibit high elastoplastic characteristics (H/E = 0.076 and H3/E2 = 0.057 GPa) and thermal stability at temperatures up to 800 °C.