Multiwavelength excitation Raman scattering study of Sb2Se3 compound: fundamental vibrational properties and secondary phases detection

This work presents a complete analysis of Raman active modes of Sb₂Se₃ measured by six different excitation wavelengths from NIR to UV, under different polarization configurations and at low temperature. Simultaneous fitting of spectra allowed the deconvolution and identification of the 28 Raman peaks obtained in monocrystalline Sb₂Se₃ sample from the 30 modes predicted by the group theory analysis for this crystalline structure. Analysis of the spectra measured under different polarization configurations yielded the preliminary assignment of the peaks symmetry, while the measurements under low temperature resulted in a fine resolution of the peaks in Raman spectra. Additionally, evaluation of the spectra of the most probable secondary phases under different excitation wavelengths allowed to define the most appropriate measurement conditions for experimental discrimination of their Raman peaks in the spectra of Sb₂Se₃ based thin films solar cells. The combination of different wavelength allows a non-destructive methodology for high sensitivity detection of main secondary phases of the Sb₂Se₃.