Siebentritt, S. ; Papathanasiou, N. ; Albert, J. ; Lux-Steiner, M.Ch.: Stability of surfaces in the chalcopyrite system. Applied Physics Letters 88 (2006), p. 151919/1-3
10.1063/1.2192638
Abstract:
It has been observed previously that the stable surfaces in chalcopyrites are the polar {112} surfaces. We present an electron microscopy study of epitaxial films of different compositions. It is shown that for both CuGaSe2 and CuInSe2 the (001) surfaces form {112} facets. With increasing Cu excess the faceting is suppressed, indicating a lower surface energy of the (001) surface than the energy of the (112) surface in the Cu-rich regime, but the (001) surface is higher in energy than the (112) surface in the Cu-poor regime. As both surfaces are polar the stabilization is attributed to defect formation.