Delafossite CuFeO2 thin films via aerosol assisted CVD: Synthesis and characterization

The optimal synthesis conditions for the growth of delafossite CuFeO2 thin films via aerosol assisted CVD were studied. An iterative synthesis process was followed until the average atomic ratio of Cu/Fe in the synthesized thin films was close to 1. TiO2 coated borosilicate was initially used as substrate. Complete characterization of selected samples revealed the formation of polycrystalline CuFeO2 in a rhombohedral phase. Small amounts of tenorite (CuO) were also observed. Further investigation of the growth of CuFeO2 was achieved using ZnO coated borosilicate substrates. The synthesized thin films were in all cases homogeneous and had an average thickness of 45 +/- 3 nm and 41 +/- 3 nm when grown onto TiO2 or ZnO, respectively. Outcomes indicated an almost negligible influence of the buffer layer on the microstructure and optical properties of CuFeO2. Therefore, the direct synthesis via AACVD technique of this bimetal and visible light absorbing oxide was verified.