title: Evidence of localized amorphous silicon clustering from Raman depth-probing of silicon nanocrystals in fused silica.
abstract: Silicon nanocrystals (Si-nc) and amorphous silicon (α-Si) produced by silicon implantation in fused silica have been studied by micro-Raman spectroscopy. Information regarding the Raman signature of the α-Si phonon excitation was extracted from Raman depth-probing measurements using the phenomenological phonon confinement model. The spectral deconvolution of the Raman measurements recorded at different laser focusing depths takes into account both the Si-nc size variation and the Si-nc spatial distribution within the sample. The phonon peak associated with α-Si around 470 cm(-1) is greatest for in-sample laser focusing, indicating that the formation of amorphous silicon is more important in the region containing a high concentration of silicon excess, where large Si-nc are located. As also observed for Si-nc systems prepared by SiO(x) layer deposition, this result demonstrates the presence of α-Si in high excess Si implanted Si-nc systems.
authors: INRS-EMT, 1650 boulevard Lionel Boulet, Varennes, QC, J3X 1S2, Canada.
authors: D
authors: D
authors: Barba
authors: F
authors: F
authors: Martin
authors: G G
authors: GG
authors: Ross