Structures of metallic glass sputtered films by using Zr-Al-Ni-Cu alloy targets

Zr-Al-Ni-Cu thin films were deposited by the radio-frequency sputtering method at low substrate temperature using three kinds of targets; Zr55Al10Ni5Cu30 bulk metallic glass target (α-BMG target), crystallized bulk metallic glass target (c-BMG target), and an elemental composite target composed of each Zr, Al, Ni chips and Cu plate. XRD profiles of the films prepared when using these targets indicated that all of the films showed amorphous structures. While XRD profiles of the films using α and c-BMG targets revealed a broad peak of 2θ=38 degree in the same way as the α-BMG target indicating amorphous structures, that of the film using elemental composite targets showed a broad peak of 2θ=42 degree, which is higher compared to the latter material. As a result of annealing the films at various temperatures for 900 s, the film using the α-BMG target showed a crystallization temperature of 748 K, higher than that of BMG with 723 K, while the other films had lower crystallization temperatures below 723 K. XRD profiles also indicated that the crystallized compounds of the films were different from those of BMG target. (author)