Formation of nanostructures on the surface of KTP single crystals by argon cluster ion beam

In this work, the surface of potassium titanyl phosphate (KTP) single crystals has been processed by argon cluster ions having low energy per atom E/N_mean = 12.5 eV/atom. The formation of periodic nanostructures has been studied using atomic force microscopy (AFM) and the power spectral density (PSD) functions. To evaluate the processing efficiency, the dependence of the etching rate of KTP on the incident angles of cluster ions has been investigated. It is shown that the average etching rate 〈V_etch〉 varies between 0.46 and 1.1 nm/min with an incident angle change from 0° to 70°. (paper)