White-emitting oxidized silicon nanocrystals: Discontinuity in spectral development with reducing size

0343173 - FZÚ 2011 RIV US eng J - Journal Article
Dohnalová, Kateřina - Ondič, Lukáš - Kůsová, Kateřina - Pelant, Ivan - Rehspringer, J.L. - Mafouana, R.-R.
White-emitting oxidized silicon nanocrystals: Discontinuity in spectral development with reducing size.
Journal of Applied Physics. Roč. 107, č. 5 (2010), 053102/1-053102/6. ISSN 0021-8979. E-ISSN 1089-7550
R&D Projects: GA AV ČR(CZ) IAA101120804; GA MŠMT LC510; GA AV ČR KJB100100903; GA ČR GA202/07/0818
Institutional research plan: CEZ:AV0Z10100521
Keywords : silicon nanocrystals * luminescence * spectral shift
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 2.064, year: 2010

Small oxidized silicon nanocrystals of average sizes below 3.5 nm are prepared using modified electrochemical etching of a silicon wafer. Modifications introduced in the etching procedure together with postetching treatment in H2O2 lead to a decrease in the nanocrystalline core size and also, to some extent, to changes in the surface oxide. The interplay between these two factors allows us to blueshift the photoluminescence (PL) spectrum from 680 down to 590 nm, which is accompanied by changes in PL dynamics. This continual development, however, stops at about 590 nm, below which abrupt switching to fast decaying blue emission band at about 430 nm was observed. Discontinuity of the spectral shift and possible relation between both bands are discussed.
Permanent Link: http://hdl.handle.net/11104/0185707