Vg. Mokerov et al., Influence of crystal orientation of the growth surface due to molecular beam epitaxy on the optical properties of Si-doped GaAs layers, SEMICONDUCT, 32(11), 1998, pp. 1175-1178
Photoluminescence (PL) spectra of GaAs (100), (111)A and (111)B layers grow
n by molecular-beam epitaxy at different ratios of the partial pressures P-
As4/P-Ga = gamma are investigated. Depending on the crystal orientation and
gamma values, either two PL bands (B- Si bands) or a single PL B-band are
observed. The B-band corresponds to band-to-band radiative recombination (e
--> h) and the Si band is attributed to optical transitions between the co
nduction band and the Si acceptor states (e --> A). The observed variations
of the PL spectra and of the type and magnitude of the electrical conducti
vity as functions of the orientation and gamma value are interpreted in ter
ms of changes in the Si-acceptor concentration and their energy spectrum as
well as a change in the ratio of the concentrations of the Si donor and ac
ceptor states. These results are explained in the framework of the kinetic
approach based on the multiplicity (energy) of the dangling chemical bonds
on the different surfaces, with the influence of the molecular flux densiti
es taken into account. (C) 1998 American Institute of Physics. [S1063-7826(
98)00711-X].