Raman Spectra of In_0.30Se_0.70Amorphous Films

Abstract

Amorphous films of In0.30 Se0.70 alloy thermally evaporated from one source onto borosilicate glass substrates were studied by Raman scattering at 300 K and 10 K. The Raman scattering spectra excited with 488 and 457.9 nm laser lines were recorded in a quasi-rectangular geometry with the use of a single channel spectrometer. All the Raman scattering spectra reveal a continuum spreading from the Rayleigh line up to about 250 cm -1 and rather featureless background due to second-order processes beyond it. The room temperature spectra show a strong feature at about 143 cm -1 that is lacking in the spectra taken at 10 K and, instead, a weak band at about 125 cm -1 is observed. The Raman scattering spectra recorded at both temperatures appear to be dependent on the excitation line within the 40-50 cm -1 range. The feature at about 143 cm -1 is attributed to Se chain modes while a weaker band at about 125 cm -1 observed at low temperature is due to Se8 ring molecules. The dynamics of the In0.30 Se0.70 films is treated in terms of a continuous random network composed of rather strongly interconnected InSe4 tetrahedral clusters.

Characterization of the Stability of Indium Tin Oxide and Functional Layers for Semitransparent Back‐Contact Applications on Cu(in,Ga)Se2Solar Cells

“…Star symbols indicate Raman peaks related to vibrational modes of MoSe 2 phase [ 51 ] and square symbols indicate Raman peaks related to an amorphous In–Se phase. [ 44–47 ] The spectra are normalized to the noise of the baseline.…”

“…The detected broad bands appear within the spectral regions that are characteristic of amorphous In-Se phases. [44][45][46][47] For the same chemical composition, Raman spectra of amorphous phases change notably with respect to the spectra of crystalline phases. [44,48] It has been reported that the amorphous In 2 Se 3 presents a broad band with a peak at 255 cm À1 and a broad band with a peak at 490 cm À1 , [44] while In x Se 1Àx presents a broad band with a peak that ranges from 190 to 255 cm À1 depending on the In/Se ratio.…”

“…Such an [51] and square symbols indicate Raman peaks related to an amorphous In-Se phase. [44][45][46][47] The spectra are normalized to the noise of the baseline.…”

“…Raman spectra obtained on exposed bare ITO and ITO/MoSe 2 back contacts as a function of the coevaporation process temperature using 785 nm excitation wavelength. Star symbols indicate Raman peaks related to vibrational modes of MoSe 2 phase[51] and square symbols indicate Raman peaks related to an amorphous In-Se phase [44][45][46][47]. The spectra are normalized to the noise of the baseline.…”