Local structure in dilute nitrides probed by X-ray absorption spectroscopy

We describe the use of X-ray absorption spectroscopy (XAS) with synchrotron radiation to study the local structure in dilute nitrides. After a brief description of the advantages of XAS to probe local atomic arrangements in semiconductor alloys and nanostructures we focus our attention on (InGa)(AsN). We discuss data which demonstrate that atomic ordering (in the form of an excess of In-N over Ga-N bonds) is present, but is significantly weaker than predicted; also we show that the experimental values for the bond lengths are in agreement with recent models which take into account strain due to pseudomorphic growth.