Photoluminescence of Si or Ge nanocrystallites embedded in silicon oxide

This paper presents the results of photoluminescence, its temperature dependence and Raman scattering investigations on magnetron co-sputtered silicon oxide films with (or without) embedded Si (or Ge) nanocrystallites. It is shown the oxide related defect origin of the visible PL centers peaked at 1.7, 2.06 and 2.30 eV. The infrared PL band centered at 1.44-1.58 eV in Si-SiOx, system has been analyzed within a quantum confinement PL model. Comparative PL investigation of Ge-SiOx system has confirmed that high energy visible PL bands (1.60-1.70 and 2.30 eV) are connected with oxide related defects in SiOx. The PL band in the spectral range of 0.75-0.85 eV in Ge-SiOx system is attributed to exciton recombination inside of Ge NCs. (c) 2006 Elsevier B.V. All rights reserved.