Emergence of triangular features on ion irradiated silicon (100) surface

Abstract

Low-energy off-normal Ar+ ion irradiation induces triangular features superimposed by nanoscale ripple patterns on Si (100) surface. Within the ion beam parameters range reported here, triangular features appear and show stronger lateral dependency on angle of incidence. Simulations performed using non-linear continuum equation incorporating dispersion term develops similar triangular features observed experimentally. Tuning parameters r1 and α as described in reference (K.M. Loew, R.M. Bradley, Phys. Rev. E. 100 (2019) 012801) generate angle and fluence like effects as in experiments for the triangular features. Experiment and simulation confirm more triangular elevations than depressions and their number increases with incidence angle up to 67∘.