PHOTOLUMINESCENCE OF NANOSTRUCTURES BASED ON GaP WITH QUANTUM DOTS OF Ge GROWN BY LIQUID-PHASE EPITAXY

Abstract

The samples of nanoheteroepitaxial structures with Ge quantum dots in a GaP matrix on Si substrates have been grown in two structural schemes using a liquid-phase epitaxy method with pulsed cooling of the substrates. The photoluminescence spectra of the samples at temperatures of 77 and 300 K are measured under excitation by laser radiation with λ = 4880 and 5145 Å. Conclusions are made about the factors that affect the spectrum and intensity of radiation of the nanostructures with quantum dots. It is found that in order to reduce nonradiative recombination in the multilayer p-n structures, it is necessary to create arrays of quantum dots in the volume of p- and n-regions, rather than in the central part of the depletion layer of the p-n junction. It is shown that the theoretical energy values for Ge quantum dots of calculated sizes are comparable with the energy of their photoluminescence maxima.