Long-range order and thermal stability of thin Co2FeSi films on GaAs(111)B

B Jenichen (1) , J Herfort (1) , K Kumakura (1, 2) , A Trampert (1)

1 PDI - Paul-Drude-Institut für Festkörperelektronik
2 NTT Basic Research Laboratories

Co 2 FeSi/GaAs(111)B hybrid structures are grown by molecular-beam epitaxy and characterized by transmission electron microscopy (TEM) and x-ray diffraction. The lattice matched Co 2 FeSi films grow in a three-dimensional island growth mode at substrate temperatures T S between T S = 100 @BULLET C and 425 @BULLET C. The structures have a stable interface up to T S = 275 @BULLET C. The films contain fully ordered L2 1 and partially ordered B2 phases. The spatial distribution of long-range order in Co 2 FeSi is characterized using a comparison of TEM images taken with superlattice reflections and the corresponding fundamental reflections. The spatial inhomogeneities of long-range order can be explained by local non-stoichiometry due to lateral segregation or stress relaxation without formation of extended defects.

Mots clés: 75.50 Bb; 81.15.Hi; 61.05.J-; 68.35.Ct

B Jenichen, J Herfort, K Kumakura, A Trampert. Long-range order and thermal stability of thin Co2FeSi films on GaAs(111)B. Journal of Physics D: Applied Physics, 2010, 43 (28), pp.285404. ⟨10.1088/0022-3727/43/28/285404⟩. ⟨hal-00597825⟩