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Dielectric films with embedded silicon Si nanocrystallites (Si-Nc) have been recognized as promising light-emitting materials for future integrated photonics based on silicon technology. This work reports a novel method of making this kind of material by high-temperature annealing of Si-rich oxide or nitride films which gives rise to the phase separation reaction and the formation of crystalline silicon nanoclusters in the films. Various characteristics of these materials were studied in detail by using transmission electron microscope, X-ray photoelectron spectroscopy (XPS), Raman, and photoluminescence (PL). Strong transverse optical (TO) mode of Si-Nc at around 516 cm(-1) was found in the Raman spectra of the annealed dielectric films. XPS studies indicate that the Si 2p spectra could be transformed from a random bonding structure (as-deposited) to a random mixing of Si-Nc with stoichiometric oxide or nitride phase after the high-temperature annealing. The energy locations of PL were found to depend on the amount of rich Si and the annealing conditions. Longer and higher temperature annealing can result in the growth of the Si-Nc size and leads to a red-shift of PL. Direct correlation among the crystallite sizes with the PL peaks was found.

This paper reviews recent progress in deposition of diumond and cubic boron nitride (c:BN)Jilnis. I/ aims a1 the efort ofpreparing smooth srrfaces. improving crystallinity and enhancing adhesion of dianiond arid cBN jilnrs. The properties of tlrese materials, ndi-stage growth process and di/jerence in synthesis of diamond aiid cBN f i l m are discussed. Resolving the nucleation and growth stages. deposition at different teniperatures. post deposition treatnteiit, possible chemistq and mechanism behind are introdiiced as well. We report the most strikitig results achieved in our laboratories including the deposition of thin sr?iooth oriented dianiond Jlni with coalescenl diamond crystals and the deposition ofthick cubic boron nitridejilnrs yielding well-resolved Xaniari spectra. The d@wce between the syntkeses ofpolycry.stallitie and tiano-crystalline dianiondfilnis are shown to be in gas phase e~rvironmcnts. While the CH, radicals are responsiblefor the growth Of polycrystalli~ie f i l m [lie CVD environnient with abundant C, dimers results in the deposition of rianoc~ysfalline diamond. Special attention dmerves manufacturirig single nystal diainond nanotips and their arrays. These single crystal diamond nam-tips have a ve,y hlgli aspect ratio, mi apical atigle of 28" and a radius of 5 nm. Finally. we present review of potential and current applications ofilianrond in electronic areas.[ZO]. Hydrocarbon concentration is usually 3% and substrate bias ranges from -70 to-300 V.