Electronic characterization of the ordering ofa-Ge with the use of x-ray-absorption near-edge structure

The $L_{\mathrm{III}}$-edge x-ray-absorption near-edge structure (XANES) of germanium is reported as a function of annealing temperature. There are no features in the XANES spectra for as-deposited films, but in an annealed sample (shown by Raman spectroscopy to be in a relaxed amorphous phase) a feature at 1221 eV appears. Upon crystallization of the sample, and additional feature at 1218 eV emerges. We conclude that the electronic environment in the relaxed state is different from that in the as-deposited state and that any accurate structural model of relaxed amorphous germanium must predict the XANES feature at 1221 eV.