Study of the surface morphology, electrophysical characteristics, and photoluminescence spectra of GaAs epitaxial films on GaAs (110) substrates

The electrophysical and phosphorescence characteristics, as well as the surface morphology, of GaAs films grown by molecular beam epitaxy on GaAs substrates with the (110) crystallographic orientation are studied. The silicon-doped epitaxial layers were grown at temperatures from 410 to 680$^{\circ}$C with arsenic-to-gallium flux ratios from 14 to 84. The ranges of the growth conditions for obtaining the smoothest epitaxial film surface are determined by atomic force microscopy. The behavior of silicon atoms in GaAs is interpreted using analysis of the photoluminescence spectra of the grown samples taking into account that silicon atoms occupy Ga or As sites, i.e., taking into account the appearance of Si$_{Ga}$ and Si$_{As}$ point defects, as well as of arsenic and gallium vacancies $V_{As}$ and $V_{Ga}$.