Raman study of insulating and conductive ZnO: (Al, Mn) thin films

• Autor(a) principal: Cerqueira, M. F.
• Data de Publicação: 2015
• Outros Autores: Viseu, T. M. R., Campos, J. Ayres de, Rolo, Anabela G., Lacerda-Arôso, T. de, Oliveira, F., Bogdanovic-Radovic, I., Alves, E., Vasilevskiy, Mikhail
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/1822/37624
• topic: Raman scattering; ZnO thin films; Al and Mn-doping; sputtering and implantation; ion implantation; local phonon modes; Raman spectroscopy; sputtering; thin films; zinc oxide; Ciências Naturais::Ciências Físicas; Science & Technology

Raman spectroscopy results obtained for undoped and Al- and/or Mn-doped ZnO thin films produced by RF-sputtering are reported. The effect of the doping method (either co-sputtering or ion implantation), the dopant type and its concentration on the Raman-active vibrational modes in these films were studied in detail. The results are discussed with focus on the peak shifts and broadening, and on the doping-induced relaxation of the symmetry selection rules. A particular attention is paid to the 520-530 cm-1 Raman band observed in all Mn containing samples and a simple theoretical model and arguments are presented in support of its relation to the local (gap) phonon mode produced by Mn atoms substituting Zn in the cationic sublattice of the ZnO crystal.