Plasma‐assisted self‐formation of nanotip arrays on the surface of Cu(In,Ga)Se2 thin films

In this paper, we report on the phenomenon of nanostructure self‐formation on the surface of Cu(In,Ga)Se 2 (CIGS) thin films during inductively coupled argon plasma treatment with its duration varied from 10 to 120 s. The initial films were grown on glass substrates using the selenization technique. During the CIGS film surface treatment in the high‐density low‐pressure radio‐frequency inductively coupled argon plasma there took place a formation of arrays of uniform vertical nanostructures, which shape with increasing processing duration changed from nanocones to nanorods and back to nanocones. A model of the nanotip plasma‐assisted self‐formation associated with the implementation of micromasking and vapor–liquid–solid mechanisms involving metallic In‐Ga (In‐Ga‐Cu) liquid alloy droplets is proposed.