Mj. Regan et A. Bienenstock, APPLICATION OF CYLINDRICAL CORRELATION-FUNCTIONS TO ANISOTROPIC SCATTERING FROM AMORPHOUS FILMS, Journal de physique. IV, 3(C8), 1993, pp. 459-462
The cylindrical pair correlation function has been utilized as a struc
tural tool in the study of anisotropic phase separation in magnetron s
puttered amorphous FexGe100-x films. Anomalous small-angle x-ray scatt
ering (ASAXS) measurements have been performed with the scattering vec
tor both in and oblique to the plane of the films, to search for aniso
tropy. The cylindrical correlation function has been calculated from t
hese measurements and indicates that there exist well-defined regions
of electron density that are elongated (7 angstrom by 12 angstrom) in
the direction of film growth. In addition, for a composition of x=6, t
hese regions are well-correlated on a length scale of 27 angstrom for
those correlation vectors oriented in the plane of the film surface, w
hereas the correlations are far weaker and longer in length for those
vectors aligned in the direction of growth, These results are in agree
ment with a previous qualitative model of packed, prolate ellipsoids o
riented in the direction of growth.