Influence of deposition conditions and annealing temperature on phase composition and structure of W-B system ion-plasma condensates

Abstract

Effects of condensation temperature and subsequent annealing on composition and structure of tungsten boride condensates obtained by ion-plasma sputtering have been studied. In the condensation temperature range 300 to 900°C, the formation of condensates with amorphous/nanocrystalline structure has been found to take place. As compared to the material being sputtered, the condensate composition is characterized by boron atomic deficiency. High-temperature vacuum annealing (Tann = 1100 to 1230°C, P < 7.10⁻⁴ Pa) results in crystallization into lower boride phases, among which the γ-W₂B is most stable. The causes of observed effect are discussed.