J. Zhang et al., DYNAMIC CHANGES IN REFLECTANCE ANISOTROPY FROM THE SI(001) SURFACE DURING GAS-SOURCE MOLECULAR-BEAM EPITAXY, Physical review. B, Condensed matter, 53(15), 1996, pp. 10107-10115
Comparisons of simultaneous reflection anisotropy (RA) and reflection
high-energy electron diffraction (RHEED) measurements during gas-sourc
e molecular-beam epitaxy of Si on Si (001) surfaces have been used to
establish a model for the dynamic changes in RA. The oscillatory behav
ior of RA is firmly linked to the periodic variations in domain covera
ge of the (2 x 1) + (1 x 2) reconstructed surface during growth under
the monolayer by monolayer growth mode. The absence of changes in doma
in coverage during growth interruption at 600 degrees C has also been
demonstrated, which substantiates the prediction of Monte Carlo simula
tions. By comparison of RA and RHEED response at high and low growth t
emperatures, it has been shown that above 650 degrees C the absence of
RA oscillations is linked to the change in growth mode from two-dimen
sional nucleation to step flow, whereas their absence at temperatures
below 550 degrees C is due to a change in the joint density of states
caused by a change in the electronic configuration. The lack of oscill
atory RA response during growth on misoriented surfaces is discussed i
n terms of the averaging process in obtaining macroscopically observab
le RA from anisotropic local polarizability.