OS06W0224 Effect of Ar gas pressure on growth, structure, and mechanical properties of sputtered Ti thin films

Abstract

The effects of sputtering gas (Ar gas) pressure on the growth and the structure of 0.3 to 0.4 μm thick Ti thin film membranes microfabricated by magnetron sputtering were studied using transmission electron microscopy. Sputtering gas pressure was varied from 0.2 Pa to 2.0 Pa. The deposited Ti films exhibited very fine structures. The Ti films deposited at 0.2 to 1.1 Pa had hexagonal close-packed structures with the preferred orientation. On the other hand, the Ti films deposited at 2.0 Pa appeared to be a mixture of a random hexagonal close-packed structure and a cubic structure. The Ti films deposited at lower Ar gas pressures had dense structures with smooth flat surfaces, however, and the rough surfaces of the Ti films were promoted by elevated Ar gas pressures. Shadowing played a very important role in the coating growth of the Ti films. The lower tensile strength values of the Ti films deposited at higher Ar gas pressures can be explained in terms of shadowing.