PbTe/SnTe superlattices were grown on (111) BaF2 substrates by molecul
ar beam epitaxy using PbTe as buffer layers. The individual layer thic
kness and number of repetitions were chosen in order to change the str
ain profile in the superlattices from completely pseudomorphic to part
ially relaxed. The superlattices structural properties were investigat
ed by making reciprocal space maps around the asymmetric (224) Bragg d
iffraction points and omega/2 Theta scans for the (222) diffraction wi
th a high resolution diffractometer in the triple axis configuration.
With the strain information obtained from the maps, the (222) omega/2
Theta scan was simulated by dynamical diffraction theory. The simulate
d spectra of the pseudomorphic superlattices, in which the in-plane la
ttice constant is assumed to be the same as the PbTe buffer throughout
the superlattice, fitted in a remarkably good agreement with the meas
ured data, indicating that almost structurally perfect samples were ob
tained. For the thicker superlattices, the (224) reciprocal space maps
revealed a complex strain profile. Our results show the importance of
detailed structural characterization on the interpretation of the ele
ctrical properties. (C) 1998 American Institute of Physics. [S0021-897
9(98)03219-8]