resumo
The high throughput synthesis of BiFeO3 and rare earth doped BiFeO3 films using a modified molecular beam epitaxy technique is reported. Optimum conditions for deposition have been established and compositionally graded Bi(1- x)NdxFeO3 (x = 0.08 to 0.24) thin films have been fabricated on platinised silicon substrate (Si/ SiO2/TiO2/Pt) with the aim of finding the optimum Nd dopant concentrations for enhanced piezoelectric properties. For x<0.12, the structure and symmetry were identical to that of the R3c BiFeO3 end member. For x > 0.20, the structure and symmetry were consistent with the NdFeO3 end member (Pnma). For compositions 0.12 < x < 0.2, a gradual transition from R3c to Pnma was observed via a mixed phase region but no compositional interval could be unambiguously identified in which the intermediate PbZrO3-like structure, reported by Karimi et al. (2009) [6], existed as a single phase. Piezoresponse force microscopy remanent hysteresis measurements of the film revealed a statistical increase in the piezoelectric response at x approximate to 0.11 within the R3c region adjacent to the mixed phase field. (c) 2012 Elsevier B.V. All rights reserved.
palavras-chave
BIFEO3
categoria
Materials Science; Physics
autores
Darby, MSB; Karpinsky, DV; Pokorny, J; Guerin, S; Kholkin, AL; Miao, S; Hayden, BE; Reaney, IM
nossos autores
Ana Maria de Oliveira e Rocha Senos
Colaborador
Andrei Kholkin
Investigador Jubilado
Dzmitry Karpinski (Karpinsky)
Bolseiro de pós-Doutoramentoagradecimentos
This work was supported by the Technology Strategy Board, UK through the Knowledge Transfer Partnership, KTP007023. The authors would like to acknowledge the financial support from the Foundation for Science and Technology of Portugal (grant number SFRH/BPD/42506/2007).