Electronic loss mechanisms in chalcopyrite based heterojunction solar cells

This article discusses the fundamental limitations imposed on Cu(In,Ga)Se-2 based heterostructure solar cells by recombination in the bulk of the abso rber and at the interface between the absorber and the CdS buffer layer. Bu lk recombination to a certain extent can be minimized by increasing the dop ing density up to a limit where tunneling currents significantly enhance re combination. We propose simple schemes for the analysis of experimentally g ained data. By comparison of theoretical models with experimental data we s how that tunneling plays a role for polycrystalline Cu(In,Ga)Se-2 in some c ases and for CuGaSe2 in general. (C) 2000 Elsevier Science S.A. All rights reserved.