Amorphous-Si:H/SiO

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multilayers with various sub-layer thicknesses were layer-by-layer deposited and in situ plasma oxidized in a plasma-enhanced chemical vapor deposition system. Nano-crystalline Si can be formed in the initial a-Si sub-layers based on the constrained crystallization principal. Raman scattering and TEM measurements were used to characterize the structure of multilayers during the formation of nc-Si/SiO

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multilayers. It was found that the annealing temperature and the a-Si:H sub-layer thickness influence on the crystallization process obviously. Photoluminescence was observed at room temperature and the PL peak position is about 750 nm. Light-emitting Diode with MOS (Metal-Oxide-Semiconductor) structure was designed and fabricated by evaporating Al electrodes on both the upper and the bottom surface of the sample. Electroluminescence at room temperature was also observed by the naked eye with the turn-on voltage of 6 V. The EL spectra contain two luminescence bands located at 520 nm and 650 nm

respectively. The influence of nc-Si and interface of nc-Si and SiO

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on the luminescent character of the device was briefly discussed.