Deposition and characterization for high-quality Ti-Ni-Cu thin films with higher Cu content

In order to attain high-quality Ti-Ni-Cu film, the surface morphologies, chemical compositions and mechanical properties of Ti-Ni-Cu thin films prepared by direct current (DC) magnetron sputtering at various processes were characterized by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and tensile tests. The type of substrates, Ar pressure and sputtering power had significant effects on the quality and chemical composition of Ti-Ni-Cu thin film. Compared with Si and SiO(2)slides, it was easier to obtain freestanding films by adopting glass or piezoid slide as substrates. The Ti-Ni-Cu thin film deposited at lower pressure (0.10 Pa) had a better density. The surface was featured with porous structure in the Ti-Ni-Cu thin film prepared by higher Ar pressure of 0.36 Pa. In addition, both the tensile strength and strain of annealed Ti-Ni-Cu thin film continuously increased with Ar pressure decreasing. Higher density contributed to the superior mechanical properties. The deposition rate firstly increased and then decreased with Ar pressure and sputtering power increasing. The composition of deposited Ti-Ni-Cu film can be tailored by changing sputter power. The deposited Ti-Ni-Cu thin films at different processing parameters were in amorphous state. In short, the present study offered the important theoretical basis for the preparation of Ti-Ni-Cu thin film with higher quality and performance. Graphic abstract