Short range ordering in amorphous In-Se films by wide-angle X-ray scattering

Wide-angle X-ray scattering studies were performed on In-Se amorphous films , obtained by thermal evaporation, with selenium content of 60 and 66 at.%. The intensities were recorded in the scattering vector range between 3 and 160 nm(-1). Structural information about the local structure of the amorph ous In-Se films has been derived from the radial distribution function usin g the curve-fitting method. The experimental results have been compared wit h model based simulations. The obtained structural parameters indicate that for In40Se60 In-In, In-Se and Se-Se contributions are involved in the near -neighbour coordination sphere. As the Se content is increased, the number of In-In bonds is reduced to zero, within the precision of the method. For both amorphous films In is tetrahedrally coordinated while Se has three nea r neighbours on the average. (C) 2000 Kluwer Academic Publishers.