Effect of low-temperature annealing on photoluminescence of silicon nanocluster structures

• Published in: Semiconductors (Woodbury, N.Y.) N.Y.), 2010-04, Vol.44 (4), p.514-518
• Main Authors: Romanyuk, B. N., Melnik, V. P., Popov, V. G., Khatsevich, I. M., Oberemok, A. S.
• Format: Article
• Language: English
• Subjects: ANNEALING; ATOMS; CHALCOGENIDES; CHARGE CARRIERS; DATA; DISPERSIONS; ELEMENTS; EMISSION; ENERGY LEVELS; EXPERIMENTAL DATA; Fabrication; HEAT TREATMENTS; INFORMATION; INTERFACES; LUMINESCENCE; Magnetic Materials; Magnetism; MATERIALS SCIENCE; MINERALS; MIXTURES; NANOSTRUCTURES; Nanotechnology; NITROGEN; NONMETALS; NUMERICAL DATA; OXIDE MINERALS; OXIDES; OXYGEN; OXYGEN COMPOUNDS; PEAKS; PHOTOLUMINESCENCE; PHOTON EMISSION; Physics; Physics and Astronomy; RECOMBINATION; SEMIMETALS; SILICA; SILICON; SILICON COMPOUNDS; SILICON OXIDES; SPECTRA; TEMPERATURE RANGE; TEMPERATURE RANGE 0065-0273 K; TEMPERATURE RANGE 0400-1000 K; Testing of Materials and Structures; Treatment
• ISSN: 1063-7826; 1090-6479
• DOI: 10.1134/S1063782610040184

Experimental data on the photoluminescence spectra of Si nanocluster structures obtained after high-temperature annealing (1150°C) of SiO x films deposited onto Si and subsequent low-temperature annealing of the films at the temperature 450°C in different ambient are reported. It is shown that the photoluminescence intensity substantially increases after low-temperature annealing and the most-pronounced effect is observed after annealing in the oxygen-nitrogen mixture. In this case, the photoluminescence spectrum is shifted to longer wavelengths and shaped as a broad band with a peak around 800 nm. The processes responsible for the increase in the PL intensity on low-temperature annealing in the oxygen-nitrogen mixture are defined by reconstruction of the Si/SiO 2 interfaces and by energy levels formed at the interfaces and involved in recombination of nonequilibrium charge carriers. The quasichemical reactions that bring about the formation of such levels involve oxygen and nitrogen atoms, and the centers, at which the reactions are initiated, are unsaturated valence bonds at the interfaces between Si nanoclusters and the SiO 2 matrix.