Properties of Va metal-B films prepared by r.f.-sputtering

Tasub(100-x)Bsub(x) alloy films were prepared by r.f.-sputtering in the chemical composition range 45 <= x <= 77. Tasub(100-x) Bsub(x) (45 <= x <= 58) films consist of the amorphous phase, while the TaB2 crystal phase was observed in Tasub(100-x)Bsub(x) (66 <= x <= 77) films. A remarkable preferred orientation with the (001) plane of TaB2 parallel to the film surface was observed in Ta34B66. The d.c. electrical conductivity of Tasub(100-x)Bsub(x) (45 <= x <= 77) films decreases with increasing boron content in the range 6.7 x 103 to 1.3 x 103 Ω-1 cm-1. The micro-Vickers hardness of Tasub(100-x) Bsub(x) (45 <= x <= 77) films was in the range 2200 to 2600 kg mm-2. (author)