Effects of RF Magnetron Sputtering Power on the Mechanical Behavior of Zr-Cu-Based Metallic Glass Thin Films.

Zirconium-based metallic glass films are promising materials for nanoelectronic and biomedical applications, but their mechanical behavior under different conditions is not well understood. This study investigates the effects of radio frequency (RF) power and test temperature on the nanostructure, morphology, and creep behavior of Zr55Cu30Al10Ni5 metallic glass films prepared by RF magnetron sputtering. The films were characterized by X-ray diffraction and microscopy, and their mechanical properties were measured by a bulge test system. The results show that the films were amorphous and exhibited a transition from noncolumnar to columnar morphology as the RF power increased from 75 W to 125 W. The columnar morphology reduced the creep resistance, Young's modulus, residual stress, and hardness of the films. The creep behavior of the films was also influenced by the test temperature, with higher temperature leading to higher creep strain and lower creep stress. The findings of this study provide insights into the optimization of the sputtering parameters and the design of zirconium-based metallic glass films for various applications.

The Effects of Stresses and Interfaces on Texture Transformation in Silver Thin Films.

Thin metal films are critical elements in nano- and micro-fabricated technologies. The texture orientation of thin films has a significant effect on applied devices. For Face-Centered Cubic (FCC) metal thin films, when the critical thickness is reached, the texture orientation can transform from (111) to (100) based on the model related to the balance between interfacial energy and strain energy. This research focused on the texture transformation of thin films under two conditions: (1) with or without an adhesion layer in the thin film and (2) with or without initial stress applied through a four-point bending load. In the experiment, two samples (silicon/silver and silicon/titanium/silver) were used to apply different initial stress/strain values and different annealing times. After annealing, an X-ray Diffractometer (XRD) was used to ascertain the preferred orientation of the thin films and the percentage of (111) and (100). Finally, Electron Back-Scattered Diffraction (EBSD) was used to observe the grain size of the thin films. The results showed that, regardless of the existence of an adhesion layer, texture transformation occurred, and this was relatively significant with Ti adhesion layers. Further, the initial stress was found to be small compared to the internal stress; thus, the initial stress imposed in the tests in this research was not significantly influenced by the texture transformation.