Thin films of amorphous germanium–nitrogen (a‐GeN) alloys prepared by the rf sputtering deposition technique have been studied by Raman scattering spectroscopy. The nitrogen content of the samples varies between zero and ≊3×1022 atoms cm−3, as determined from nuclear reaction analysis data. Modifications of the structural characteristics of the Ge–N alloys, probed through their phonon density, were investigated as a function of the nitrogen concentration. In addition to an increase of the network’s topological disorder, nitrogen is responsible, at relatively high concentrations, for a structural transition in the a‐Ge host. The optical and electronic characterization of the samples confirm these changes which are highly dependent on the nitrogen concentration.

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