Influence of Sputtering Power and Gas Pressure on the Preparation of Tungsten Films by DC Magnetron Sputtering

Using DC magnetron sputtering technology, a tungsten film was prepared on a Si substrate at room temperature. The effects of sputtering power and sputtering pressure on the deposition rate, microstructure, and phase structure of tungsten films were researched. Atomic force microscope, XRD, four-probe resistance measurement, profiler, etc. were used to characterize the structure and electrical properties of the film. The results show that the deposition rate of the film is affected by the sputtering power and the gas pressure. The deposition rate increases linearly with the increase of the power, and first increases to a peak and then decreases with the increase of the gas pressure. The resistivity and surface roughness of the film depend on the sputtering pressure, and increase with the increase of the sputtering pressure. The increase in the resistivity of the film may be caused by the increase in the surface roughness. Under constant sputtering power, the formation of α-W mainly depends on the sputtering gas pressure. All β-W phases are formed under high pressure, but for the sputtering power is large enough, under higher pressure, the formation of some α-W phases will also be observed. The formation of the specific phase structure (α-W/β-W) in the tungsten film is not only dependent on the deposition pressure, but also related to the sputtering power, which may be related to the energy of the atoms incident on the substrate. © 2022, Science Press. All right reserved.