Exciton spectroscopy and assessment of crystallization of amorphous (PbBr₂)_0.9(CuBr)_0.1films

Abstract

Amorphous (PbBr2)0.9(CuBr)0.1 films have been obtained by quench deposition of the mixture of PbBr2 and CuBr. Upon crystallization of the films, Cu+ ions aggregate to form very small CuBr crystallites, which are uniformly embedded in the crystalline PbBr2 matrix, exhibiting blue-shifted CuBr exciton absorption. Despite the precipitation of the CuBr crystallites, the resulting films retain a relatively flat surface (rms roughness, ~15 nm for films with ~800 nm thickness).