Raman Scattering Study Of Zincblende Inxga1-xn Alloys

We report on first-order micro-Raman and resonant micro-Raman scattering measurements on c-InxGa1-xN (0 ≤ x ≤ 0.31) epitaxial layers. We have found that both, the transverse-optical (TO) and longitudinal-optical (LO) phonons of InxGa1-xN alloy exhibit a one-mode-type behavior. Their frequencies at Γ lie on straight lines connecting the corresponding values obtained for the c-GaN and c-InN binary compounds. Evidence for phase separation is shown in the sample with the alloy composition x = 0.31. The Raman spectra, with excitation energy close to 2.4 eV, show an enhanced additional peak, with frequency between the values found for the LO and TO phonon modes of the C-In0.31Ga0.69N epitaxial layer. We ascribed this peak to the LO phonon mode of a minority phase with In content of ≈0.80.2161769774Tabata, A., Lima, A.P., Teles, L.K., Scolfaro, L.M.R., Leite, J.R., Lemos, V., Schöttker, B., Lischka, K., (1999) Appl. Phys. Lett., 74, p. 362Tabata, A., Leite, J.R., Lima, A.P., Silveira, E., Lemos, V., Schöttker, B., Frey, T., Lischka, K., (1999) Appl. Phys. Lett., 75, p. 1095Tabata, A., Enderlein, R., Leite, J.R., Da Silva, S.W., Galzerani, J.C., Schikora, D., Kloidt, M., Lischka, K., (1996) J. Appl. Phys., 79, p. 4137Chang, I.F., Mitra, S.S., (1968) Phys. Rev., 172, p. 924Bechstedt, F., Grille, H., (1999) Phys. Stat. Sol. (B), 216, p. 761Harima, H., Inoue, T., Nakashima, S., Okumura, H., Ishida, Y., Yoshida, S., Koizumi, T., Bechstedt, F., (1999) Appl. Phys. Lett., 74, p. 191Wakahara, A., Tokuda, T., Dang, X.Z., Noda, S., Sasaki, A., (1997) Appl. Phys. Lett., 71, p. 906Ho, I.H., Stringfellow, G., (1996) Appl. Phys. Lett., 69, p. 270