The sputtering effects of cluster ion beams

It has been observed that a cluster ion which contains several thousands of atoms produces unique sputtering effects. It has a high yield and a strong smoothing effect for various materials such as CVD diamond films, In this work, the sputtering yield, surface smoothing and angular distribution of the sputtered atoms have been measured, and the different sputtering mechanisms of cluster ions have been revealed. Cu films Were irradiated with Ar cluster ion beams accelerated up to 20keV, at several incident angles. From the energy and incident angle dependence of the sputtering yield, it was seen that the energy density is responsible for the sputtering. The Cu surfaces irradiated with Ar cluster ions were observed by Atomic Force Microscope. The surface roughness was smallest at normal incidence, and the surface roughness increased with the incident angle. A ripple structure was observed at incident angle of 60 degrees. The angular distribution of the sputtered atoms displayed an under-cosine shape at normal incidence, and many sputtered atoms were distributed in a lateral direction. a single trace of an Ar cluster ion impact measured by STM confirmed this result.