Thermal stability of magnetron sputtered Si–B–C–N materials at temperatures up to 1700 °C

Thermal stability of deposited Si–B–C–N materials (film fragments or powders without a substrate) in inert gases (He and Ar) up to 1700 °C was investigated using differential scanning calorimetry, high-resolution thermogravimetry and X-ray diffraction measurements. Amorphous Si–B–C–N films were fabricated by dc magnetron co-sputtering of a single B4C–Si target in two nitrogen–argon gas mixtures (50% N2 + 50% Ar or 25% N2 + 75% Ar). It was found that the deposited Si–B–C–N materials can be more stable at high temperatures in the inert atmosphere than the usually used substrates (e.g. SiC or BN). The materials with the compositions (in at.%) Si32–33B10C2N50–51, for which N/(Si + B + C) = 1.1–1.2, retained their amorphous structure up to 1600 °C without any structural transformations and detectable mass changes.