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conferenceseries
.com
Volume 8
Journal of Biotechnology and Biomaterials
ISSN: 2155-952X
Biomaterials 2018
March 05-06, 2018
March 05-06, 2018 | Berlin, Germany
3
rd
Annual Conference and Expo on
Biomaterials
FIB-SEM and HRTEM investigations of microstructure of chalcopyrite CuAlS2 thin films
R Brini
1
, G Schmerber
2
and
J Werckmann
2
1
Ecole Nationale d'Ingénieurs de Tunis (ENIT), Tunisia
2
Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), France
W
e investigate themicrostructure of chalcopyrite CuAlS
2
thin films deposited on silicon (111) substrate.The polycrystalline
films with different preferred grain orientations are grown by thermal evaporation from pure powder of synthesis
deposited in elemental sources. The CuAlS
2
films were analyzed using focused ion beam scanning electron microscopy
(FIB-SEM) and high-resolution transmission electron microscopy (HRTEM). FIB-SEM cross-section images reveal that
the irregular-shaped particles are embedded in the film and that the surface region and the bulk are structurally similar,
with no ordered defect chalcopyrite structure. However, their composition is slightly different, indicating that they can have
different point defects. Microstructure properties of the films using HRTEM highlight grains in (112) textured films with
sharp contrasts at the grain boundaries, whereas grains in (220/204) textured films give only weak contrasts indicating a
preferential population of electronically rather inactive grain boundaries. Non-chalcopyrite ordering of the metal atoms in
CuAlS
2
is observed by HRTEM, which is identified as a CuAu-type ordering. Sharp spots in electron diffraction patterns show
the ordered Cu and Al atomically planes alternating along the [001] direction over a long range. The CuAu-ordered structure
coexists with the chalcopyrite ordered structure, in well agreement with theoretical prediction. This study shows that dual
beam FIB-SEM technique turns out to be an easy, less time consuming and useful method to characterize the crystallites of
CuAlS
2
films in cross-section view, compared with the results obtained by HRTEM.
brini_rawdha@yahoo.frJ Biotechnol Biomater 2018, Volume 8
DOI: 10.4172/2155-952X-C1-089