Defects analysis at the nanometric scale in Ca3Co4O9 thin films

Moubah, R.; Colis, S.; Ulhaq-Bouillet, C.; Dinia, A.
January 2010
Applied Physics Letters;1/25/2010, Vol. 96 Issue 4, p041902
Academic Journal
We report on the nature and origin of structural defects at a nanometric scale in incommensurate Ca3Co4O9 thin films deposited by pulsed laser ablation on Al2O3(001) substrates. X-ray diffraction suggests that the deposited films have a well defined texture and that are free of spurious phases. However, cross section scanning high resolution transmission electron microscopy observations show the presence of regions with different kinds of stacking. Such regions present different chemical compositions from that of Ca3Co4O9 and are not detectable in diffraction mode. The local chemical analysis and the interplane distance measurement suggest that these defects correspond to the formation of the CaCo2O4 spurious phase. This phase has a similar structure and close lattice parameters with those of Ca3Co4O9. The origin of the formation of CaCo2O4 is discussed in terms of (i) strains due to the substrate which tend to suppress the incommensurability of the system, and (ii) local chemical nonstoichiometry.


Related Articles

  • Electrically robust ultralong nanowires of NiSi, Ni2Si, and Ni31Si12. Zhen Zhang; Hellström, Per-Erik; Östling, Mikael; Shi-Li Zhang; Jun Lu // Applied Physics Letters;1/23/2006, Vol. 88 Issue 4, p043104 

    Mass fabrication of directly accessible, ultralong, uniform Si nanowires is realized by employing a controllable and reproducible method based on standard Si technology. High-conductivity polycrystalline Ni-silicide nanowires around 30 nm by 30 nm in cross section, able to support extremely high...

  • Preventing optical deactivation of nanocluster Si sensitized Er using nanometer-thin SiNx/SiO2:Er heterolayer thin film. In Yong Kim; Kyung Joong Kim; Shin, Jung H. // Journal of Applied Physics;Oct2010, Vol. 108 Issue 7, p073101 

    Multilayer thin films consisting of nanometer-thin, Er-doped luminescent layers (either SiO2:Er or Si3N4:Er) interlaced with nanometer-thin, Si-rich sensitizing layers (either Si-rich oxide or Si-rich nitride) are proposed as a solution to loss of Er3+ optical activity during nanocluster Si...

  • Mechanical strength lowering in submicron Cu thin films by moderate DC current. Niu, R. M.; Zhang, J.; Wang, Z. J.; Liu, G.; Zhang, G. J.; Ding, X. D.; Sun, J. // Applied Physics A: Materials Science & Processing;Nov2009, Vol. 97 Issue 2, p369 

    This letter reports an experimental investigation into the direct current (DC) induced reduction in the yield strength of 60∼700-nm-thick Cu films. Results show that the larger the current density and the thinner the film, the greater the reduction when the film thickness is below about 340...

  • Correlation between photoluminescence properties and morphology of laser-ablated Si/SiO[sub x] nanostructured films. Kabashin, A. V.; Sylvestre, J.-P.; Patskovsky, S.; Meunier, M. // Journal of Applied Physics;3/1/2002, Vol. 91 Issue 5, p3248 

    Pulsed laser ablation in an inert gas has been used to fabricate films containing silicon nanocrystals. We show that film microstructure is one of the main factors, determining long-term photoluminescence (PL) properties. Films with different porosity were found to exhibit PL signals with quite...

  • Fabrication and characterization of highly textured Nd–Fe–B thin film with a nanosized columnar grain structure. You, C. Y.; Takahashi, Y. K.; Hono, K. // Journal of Applied Physics;Sep2010, Vol. 108 Issue 4, p043901 

    We have fabricated a highly textured Nd–Fe–B thin film with a hard magnetic performance: Mr=1.39 T, Hc=827 kA/m, and (BH)max=358 kJ/m3. The microstructure of the film was characterized in detail by cross-sectional and plane-view transmission electron microscopy observations. The...

  • Nanoscale ablation on patterned diamondlike carbon film with femtosecond laser pulses. Miyaji, Godai; Miyazaki, Kenzo // Applied Physics Letters;9/17/2007, Vol. 91 Issue 12, p123102 

    The authors have studied the origin of nanostructure formation on diamondlike carbon film in femtosecond laser ablation at low fluence. Using the thin film target patterned with submicrometer-size stripes, they have observed that the nanostructure starts to be formed on the crest of stripes...

  • Determination of in-depth density profiles of multilayer structures. Kessels, M. J. H.; Bijkerk, F.; Tichelaar, F. D.; Verhoeven, J. // Journal of Applied Physics;5/1/2005, Vol. 97 Issue 9, p093513 

    We developed and demonstrate an analysis method in which we calibrate the intensity scale of cross-sectional transmission electron microscopy (TEM) using Cu Kα reflectometry. This results in quantitative in-depth density profiles of multilayer structures. Only three free parameters are needed...

  • Density inhomogeneity in ferroelectric thin films. Jiang-Li Cao; Solbach, Axel; Klemradt, Uwe; Weirich, Thomas; Mayer, Joachim; Böttger, Ulrich; Schorn, Peter J.; Waser, Rainer // Applied Physics Letters;7/31/2006, Vol. 89 Issue 5, p052901 

    Structural investigations of Pb(Zr,Ti)O3 (PZT) ferroelectric thin films derived by chemical solution deposition on Pt/TiOx electrode stacks were performed using grazing incidence x-ray specular reflectivity of synchrotron radiation and transmission electron microscopy. A density inhomogeneity,...

  • Size-dependent model for thin film and nanowire thermal conductivity. McGaughey, Alan J. H.; Landry, Eric S.; Sellan, Daniel P.; Amon, Cristina H. // Applied Physics Letters;9/26/2011, Vol. 99 Issue 13, p131904 

    We present an analytical model for the size-dependence of thin film and nanowire thermal conductivity and compare the predictions to experimental measurements on silicon nanostructures. The model contains no fitting parameters and only requires the bulk lattice constant, bulk thermal...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics