Silicon-doped epitaxial films grown on GaAs(110) substrates: the surface morphology, electrical characteristics, and photoluminescence spectra

The results of studies of the surface morphology, electrical characteristics, and photoluminescence properties of epitaxial GaAs films grown by molecular-beam epitaxy on GaAs(110) substrates and doped with Si are reported. A series of samples is grown at a temperature of 580$^{\circ}$C with the arsenic/gallium flow ratio in the range from 14 to 80. By analyzing the photoluminescence spectra of the samples, the behavior of Si atoms in GaAs is interpreted with consideration for the occupation of Ga or As sites by Si atoms (i.e., for the formation of Si$_{\mathrm{Ga}}$ and Si$_{\mathrm{As}}$ point defects) and the formation of vacancies of arsenic and gallium $V_{\mathrm{As}}$ and $V_{\mathrm{Ga}}$. In the analysis, the photoluminescence spectra of the samples on (110)-oriented substrates are compared with the photoluminescence spectra of similar samples on (100)- and (111)A-oriented substrates.