Structure and Optical Properties of Silicon Layers with GaSb Nanocrystals Created by Ion-Beam Synthesis

We have studied the ion-beam synthesis of GaSb nanocrystals in Si by high-fluence "hot" implantation of Sb and Ga ions followed by thermal annealing. The Rutherford backscattering, transmission electron microscopy/transmission electron diffraction, Raman spectroscopy and photoluminescence were used to characterize the implanted layers. It was found that the nanocrystal size increases from 5 to 60 nm in the samples annealed at 900 degrees C up to 20-90 nm in those annealed at 1100 degrees C. For the samples annealed at 900 degrees C a broad band in the region of 0.75-1.05 eV is registered in the photoluminescence spectra. The nature of this photoluminescence band is discussed.