Transparent conductive oxide materials (TCO) are currently under development for use as electrodes in optical systems such as photovoltaics and flat panel displays. Indium-tin based oxides and cadmium-tin based oxides have been investigated in the past but have received more attention recently due to their high electron mobilities. The mechanisms for conduction in these systems are not fully understood, but the distribution of cations within the lattice is thought to be of importance. We are currently studying the Cd1+xIn2-2xSnxO4 system for use as a TCO material. In particular, we are interested in the effect of the crystallography and cation distributions in this material upon its electro-optical properties.
The investigation of cation distributions in this spinel system presents special challenges to purely diffraction based methods. X-ray diffraction cannot be used to assess the cation distribution for this system due to the similar x-ray atomic scattering factors for the cations involved.