Raman spectroscopy of GeSe and AgGeSe thin films

CONDE GARRIDO, J. M.; PIARRISTEGUY, A.; LE PARC, L.; MARIA ANDREA UREÑA; FONTANA, M.; ARCONDO, B.; PRADEL, A.

Brasov

Conferencia; 6th International Conference On Amorphous and Nanostructured Chalcogenides (ANC 6); 2013

The structural properties of Agx(Ge0.25Se0.75)100-x thin films (where x=0, 7, 10, 15, 20 and 25 at. %) were studied. The films were prepared by pulsed laser deposition using bulk glass targets of the studied ternary system and deposited onto microscope slides. Their amorphous structures were confirmed by XRD (X-ray Diffraction). The effect of the silver content on the films structures was analysed by Raman spectroscopy. Typical Raman vibration modes were observed in the Ge0.25Se0.75 binary film: Ge-Se corner-sharing tetrahedra mode (CS) at 199 cm-1, edge sharing tetrahedra mode (ES) at 217 cm-1, and Se-Se mode at 255 cm-1. In the Agx(Ge0.25Se0.75)100-x ternary thin films, the same modes were observed but with a red shift. An intensity reduction of the ES and Se-Se bands with the increase of silver content was also observed. In a previous work [1], morphology and optical properties of the films had been studied. Refractive index and the optical band gap energy had been determined. A decrease in the optical band gap and an increase in the refractive index had been observed with the increase of Ag content. Structural studies were applied with the aim of explaining the optical behavior