Raman Scattering Spectra in Be-Implanted GaN Epilayers
Tóm tắt
Ion-implantation has been an interesting topic on impurity-doping in GaN. Raman measurement is a strong tool for the characterization of semiconductors. We have investigated the Raman scattering spectra in Be-implanted GaN epilayers. In as-implanted GaN, new Raman bands at ∼310, ∼360, 669 cm−1 appeared. From phonon-dispersion curves for hexagonal GaN, the ∼300 cm−1 and 669 cm−1 bands were assigned to the highest acoustic-phonon branch and the optical-phonon branch at the Brillouin zone boundaries, respectively. Two sharp bands at 168 and 199 cm−1 were observed in the Raman spectra of Be-implanted GaN after post-implantation annealing treatments. We tentatively assign these two bands to Be-related local vibrational modes.
Tài liệu tham khảo
S. Nakamura and G. Fasol, “The Blue Laser Diode-Gallium-Nitride Based Light Emitter and Laser” (Springer, New York, 1997).
J. I. Pankove and J. A. Hutchby, J. Appl. Phys. 47, 5387 (1976)
J. I. Pankove and J. A. Hutchby, Appl. Phys. Lett. 24, 281 (1974)
C. J. Eiting, P. A. Grudoski, R. D. Dupuis, H. Hsia, Z. Tang, D. Becher, H. Kuo, G. E. Stillman, and M. Feng, Appl. Phys. Lett. 73, 3875 (1998)
J. C. Zolper, J. Cryst. Growth 178, 157 (1997)
J. C. Zolper, H. H. Tan, J. S. Williams, J. Zou, D. J. H. Cockayne, S. J. Pearton, M. H. Crawford, and R. F. Karlicek Jr, Appl. Phys. Lett. 70, 2729 (1997)
C. H. Seager, S. M. Myers, G. A. Petersen, J. Han, and T. Headley, J. Appl. Phys. 85, 2568 (1999)
J. Q. Duan, B. R. Zhang, and Y. X. Zhang, L. P. Wang, and G. G. Qin, G. Y. Zhang, Y. Z. Tong, S. X. Jin, Z. J. Yang, X. Zhang, and Z. H. Xu, J. Appl. Phys. 82, 5745 (1997)
H. Siegle, G. Kaczmarczyk, L. Filippidis, A. P. Litvinchuk, A. Hoffmann, and C. Thomsen, Phys. Rev. B55, 7000 (1997)
D. Behr, R. Niebuhr, J. Wagner, K. -H. Bachem, and U. Kaufman, Appl. Phys. Lett. 70, 363 (1997)
Chris G. Van De Walle and Sukit Limpijumnong, Phys. Rev. B 63, 245205(2001).