M. Gailhanou et al., X-RAY-DIFFRACTION ANALYSIS OF LOW MISMATCH EPITAXIAL LAYERS GROWN ON MISORIENTED SUBSTRATES, Journal of crystal growth, 140(1-2), 1994, pp. 205-212
Large errors may occur in the X-ray diffraction determination of epita
xial layer mismatch, thicknesses or/and periodicity if the substrate m
iscut angle is not taken into account. Misoriented sample rocking curv
es are indeed strongly affected when the azimuth angle is changed, eve
n in the case of a nearly symmetric reflection. This effect is investi
gated by directly mapping the reciprocal structure of a GaAs/AlAs mult
ilayer grown on a 4-degrees misoriented GaAs substrate. The measuremen
ts, performed using a triple-crystal-like X-ray diffraction technique,
agree well with a model in terms of interfaces and lattice plane tilt
s. Simple relations based on this model are given to deduce the layer
structural parameters from the rocking curves.