Ripple patterns over oblique Ar+ sputtered SiC/Si(111) surfaces: Role of preferential sputtering

Controlled surface structuring of amorphous silicon carbide (a-SiC) thin films as grown on silicon substrates Si (111) by Radio Frequency (RF) sputtering and irradiation of obliquely incident 80 keV Ar+ ion beam has been investigated. Sub-wavelength ripple patterns with wave-vector parallel to the ion beam projection are found to evolve on argon sputtered surfaces. Studies reveal that the temporal parameters such as ripple wavelength and amplitude, ordering and homogeneity of these patterns vary non-linearly with argon ion fluence. The formation of such surface structures is attributed to the preferential sputtering of silicon in comparison to carbon. Our results reveal that ion irradiation can be exploited to fabricate controlled surface nanostructures by optimizing the irradiation parameters.

Automated summary

Controlled surface structuring of amorphous silicon carbide thin films on silicon substrates by RF sputtering and obliquely incident Ar+ ion beam irradiation was investigated. Sub-wavelength ripple patterns were found to evolve on argon sputtered surfaces, and their parameters varied nonlinearly with the ion fluence. The preferential sputtering of silicon over carbon is responsible for the formation of these surface structures, and ion irradiation can be utilized to fabricate controlled surface nanostructures by optimizing the irradiation parameters.