T. Yodo, ANISOTROPIC STRAIN ESTIMATED FROM LATTICE-PARAMETERS MEASURED BY BONDMETHOD USING X-RAY-DIFFRACTION, IN MOLECULAR-BEAM EPITAXY-GROWN GAAS SI(001)/, JPN J A P 1, 37(2), 1998, pp. 450-454
x-, y- and z-components of lattice parameters on GaAs in GaAs films gr
own on Si(001) substrates by molecular-beam epitaxy have been experime
ntally measured from (004), (115) and (404) diffractions of GaAs by th
e Bond method using X-ray diffraction (XRD). The anisotropic strain on
GaAs is estimated from the difference in each component of lattice pa
rameters between the film and the GaAs bulk crystal. In-plane componen
ts of mechanical stress on GaAs are estimated from the measurement of
substrate curvature using double-crystal XRD. The elastic strain is al
so estimated from the stress, assuming an elastic distortion of the la
ttice. However, it does not coincide with the strain derived from latt
ice parameters. The difference in the strain estimated by the two meth
ods is largely especially near the interface, indicating strong, aniso
tropic and plastic deformation of the lattice, so that it can no longe
r be regarded as an elastic body. It is probably caused by lattice and
stress relaxation related to the anisotropy of dislocations in the fi
lm.