Abstract
In this paper, we demonstrated direct formation of large area Cu(In,Ga)Se <sub>2</sub> nanotip arrays (CIGS NTRs) by using one step Ar+ milling process without template. By controlling milling time and incident angles, the length of CIGS NTRs with adjustable tilting orientations can be precisely controlled. Formation criteria of these CIGS NTRs have been discussed in terms of surface curvature, multiple components, and crystal quality, resulting in a highly anisotropic milling effect. The CIGS NTRs have very low reflectance < 0.1 % at incident wavelengths between 300 nm to 1200 nm. We believe that our unique approach of creating CIGS NTRs, including (i) one-step fast process free of template, (ii) easy integration with in-line sputtering process, and (iii) no post-seleneizatoin process can lead to further significant progress in fundamental research as well as practical applications. © OSA 2013.