Studies on grain boundaries in nanocrystalline silicon grown by Hot-Wire CVD
نویسندگان
چکیده
The use of a tantalum wire in Hot-Wire Chemical Vapour Deposition has allowed the deposition of dense nanocrystalline silicon at low filament temperatures (1550oC). A transition in crystalline preferential orientation from (220) to (111) was observed around 1700oC. Transmission Electron Microscopy images, together with Secondary Ion Mass Spectrometry measurements, suggested that no oxidation occurred in material obtained at low filament temperature, due to the high density of the tissue surrounding grain boundaries. Greater amount of SiH3 radicals formed at these temperatures seemed to be responsible of the higher density.
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