Exciton spectroscopy and assessment of crystallization of amorphous (PbBr2)0.9(CuBr)0.1films

Amorphous (PbBr 2 ) 0.9 (CuBr) 0.1 films have been obtained by quench deposition of the mixture of PbBr 2 and CuBr. Upon crystallization of the films, Cu + ions aggregate to form very small CuBr crystallites, which are uniformly embedded in the crystalline PbBr 2 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).