Non-equilibrium Phases Formed in Cu–In–Se–Te System Synthesized by Melt-Quench Method

Non-equilibrium phases formed in melt-quenched Cu In(SexTe1-x)2system, where x = 0.1, 0.2, 0.4, 0.5, 0.6,0.8 and 0.9, have been studied using Rietveld refinement of the crystal structure and Raman spectroscopy. Results of structure refinement have showed that all the samples, except the Cu In(Se0.1Te0.9)2, are heterogeneous. All the observed non-equilibrium phases are quaternary system and are found to have chalcopyrite structure(I"42d), in accordance with the Cu In Te2–Cu In Se2 phase diagram. The lattice constants deduced from the refinement have showed linear variation with Se content. A detailed analysis of the characteristic A1 modes present in the Raman spectrum of individual sample has corroborated the results obtained from the structure analysis. The position of A1 mode of individual phase is found to vary linearly with Se content, which suggests that Cu In(SexTe1-x)2system exhibits single-mode behaviour.

Non-equilibrium Phases Formed in Cu-In-Se-Te System Synthesized by Melt-Quench Method

Non-equilibrium phases formed in melt-quenched CuIn(Se_xTe_1-x )₂ system, where x = 0.1, 0.2, 0.4, 0.5, 0.6, 0.8 and 0.9, have been studied using Rietveld refinement of the crystal structure and Raman spectroscopy. Results of structure refinement have showed that all the samples, except the CuIn(Se_0.1Te_0.9)₂, are heterogeneous. All the observed non-equilibrium phases are quaternary system and are found to have chalcopyrite structure (I42d), in accordance with the CuInTe₂-CuInSe₂ phase diagram. The lattice constants deduced from the refinement have showed linear variation with Se content. A detailed analysis of the characteristic A₁ modes present in the Raman spectrum of individual sample has corroborated the results obtained from the structure analysis. The position of A₁ mode of individual phase is found to vary linearly with Se content, which suggests that CuIn(Se_xTe_1-x)₂ system exhibits single-mode behaviour.